Cretaceous–Paleogene extinction event

1039:, a group of highly diverse, numerous, and widely distributed shelled cephalopods. The extinction of belemnites enabled surviving cephalopod clades to fill their niches. Ammonite genera became extinct at or near the K–Pg boundary; there was a smaller and slower extinction of ammonite genera prior to the boundary associated with a late Cretaceous marine regression, and a small, gradual reduction in ammonite diversity occurred throughout the very late Cretaceous. Researchers have pointed out that the reproductive strategy of the surviving nautiloids, which rely upon few and larger eggs, played a role in outsurviving their ammonoid counterparts through the extinction event. The ammonoids utilized a planktonic strategy of reproduction (numerous eggs and planktonic larvae), which would have been devastated by the K–Pg extinction event. Additional research has shown that subsequent to this elimination of ammonoids from the global biota, nautiloids began an evolutionary radiation into shell shapes and complexities theretofore known only from ammonoids. 2534:, Sierra Petersen and colleagues argue that there were two separate extinction events near the Cretaceous–Paleogene boundary, with one correlating to Deccan Trap volcanism and one correlated with the Chicxulub impact. The team analyzed combined extinction patterns using a new clumped isotope temperature record from a hiatus-free, expanded K–Pg boundary section. They documented a 7.8±3.3 °C warming synchronous with the onset of Deccan Traps volcanism and a second, smaller warming at the time of meteorite impact. They suggested that local warming had been amplified due to the simultaneous disappearance of continental or sea ice. Intra-shell variability indicates a possible reduction in seasonality after Deccan eruptions began, continuing through the meteorite event. Species extinction at Seymour Island occurred in two pulses that coincide with the two observed warming events, directly linking the end-Cretaceous extinction at this site to both volcanic and meteorite events via climate change. 2436:. While his assertion was not initially well-received, later intensive field studies of fossil beds lent weight to his claim. Eventually, most paleontologists began to accept the idea that the mass extinctions at the end of the Cretaceous were largely or at least partly due to a massive Earth impact. Even Walter Alvarez acknowledged that other major changes might have contributed to the extinctions. More recent arguments against the Deccan Traps as an extinction cause include that the timeline of Deccan Traps activity and pulses of climate change has been found by some studies to be asynchronous, that palynological changes do not coincide with intervals of volcanism, and that many sites show climatic stability during the latest Maastrichtian and no sign of major disruptions caused by volcanism. Multiple modelling studies conclude that an impact event, not volcanism, fits best with available evidence of extinction patterns. 1653:

devastation and mass extinction of plants at the K–Pg boundary sections, although there were substantial megafloral changes before the boundary. In North America, approximately 57% of plant species became extinct. In high southern hemisphere latitudes, such as New Zealand and Antarctica, the mass die-off of flora caused no significant turnover in species, but dramatic and short-term changes in the relative abundance of plant groups. European flora was also less affected, most likely due to its distance from the site of the Chicxulub impact. In northern Alaska and the Anadyr-Koryak region of Russia, the flora was minimally impacted. Another line of evidence of a major floral extinction is that the divergence rate of subviral pathogens of angiosperms sharply decreased, which indicates an enormous reduction in the number of flowering plants. However, phylogenetic evidence shows no mass angiosperm extinction.

1404:) helps to understand their full extinction in contrast with their close relatives, the crocodilians. Ectothermic ("cold-blooded") crocodiles have very limited needs for food (they can survive several months without eating), while endothermic ("warm-blooded") animals of similar size need much more food to sustain their faster metabolism. Thus, under the circumstances of food chain disruption previously mentioned, non-avian dinosaurs died out, while some crocodiles survived. In this context, the survival of other endothermic animals, such as some birds and mammals, could be due, among other reasons, to their smaller needs for food, related to their small size at the extinction epoch. Prolonged cold is unlikely to have been a reason for the extinction of non-avian dinosaurs given the adaptations of many dinosaurs to cold environments. 1555:, were wiped out. Only a small fraction of ground and water-dwelling Cretaceous bird species survived the impact, giving rise to today's birds. The only bird group known for certain to have survived the K–Pg boundary is the Aves. Avians may have been able to survive the extinction as a result of their abilities to dive, swim, or seek shelter in water and marshlands. Many species of avians can build burrows, or nest in tree holes, or termite nests, all of which provided shelter from the environmental effects at the K–Pg boundary. Long-term survival past the boundary was assured as a result of filling ecological niches left empty by extinction of non-avian dinosaurs. Based on molecular sequencing and fossil dating, many species of birds (the 2329: 85: 2068: 1607:). In the Hell Creek beds of North America, at least half of the ten known multituberculate species and all eleven metatherians species are not found above the boundary. Multituberculates in Europe and North America survived relatively unscathed and quickly bounced back in the Paleocene, but Asian forms were devastated, never again to represent a significant component of mammalian fauna. A recent study indicates that metatherians suffered the heaviest losses at the K–Pg event, followed by multituberculates, while eutherians recovered the quickest. K–Pg boundary mammalian species were generally small, comparable in size to 56: 2294:-containing rock usually present in the shallow seabed of the region; it had been almost entirely removed, vaporized into the atmosphere. The impactor was large enough to create a 190-kilometer-wide (120 mi) peak ring, to melt, shock, and eject deep granite, to create colossal water movements, and to eject an immense quantity of vaporized rock and sulfates into the atmosphere, where they would have persisted for several years. This worldwide dispersal of dust and sulfates would have affected climate catastrophically, led to large temperature drops, and devastated the food chain. 1280:, a diverse group of large predatory marine reptiles, also became extinct. Fossil evidence indicates that squamates generally suffered very heavy losses in the K–Pg event, only recovering 10 million years after it. The extinction of Cretaceous lizards and snakes may have led to the evolution of modern groups such as iguanas, monitor lizards, and boas. The diversification of crown group snakes has been linked to the biotic recovery in the aftermath of the K-Pg extinction event. Pan-Gekkotans weathered the extinction event well, with multiple lineages likely surviving. 2429:

time of the extinction event. Not only did the climate temperature increase, but the water temperature decreased, causing a drastic decrease in marine diversity. Evidence from Tunisia indicates that marine life was deleteriously affected by a major period of increased warmth and humidity linked to a pulse of intense Deccan Traps activity, and that marine extinctions there began before the impact event. Charophyte declines in the Songliao Basin, China before the asteroid impact have been concluded to be connected to climate changes caused by Deccan Traps activity.

882: 693:, because such communities rely less directly on food from living plants, and more on detritus washed in from the land, protecting them from extinction. Modern crocodilians can live as scavengers and survive for months without food, and their young are small, grow slowly, and feed largely on invertebrates and dead organisms for their first few years. These characteristics have been linked to crocodilian survival at the end of the Cretaceous. Similar, but more complex patterns have been found in the oceans. Extinction was more severe among animals living in the 1397:

record is simply not good enough to permit researchers to distinguish between the options. There is no evidence that late Maastrichtian non-avian dinosaurs could burrow, swim, or dive, which suggests they were unable to shelter themselves from the worst parts of any environmental stress that occurred at the K–Pg boundary. It is possible that small dinosaurs (other than birds) did survive, but they would have been deprived of food, as herbivorous dinosaurs would have found plant material scarce and carnivores would have quickly found prey in short supply.

16267: 1150:, apparently precipitated by the K–Pg extinction event; the marine and freshwater environments of fishes mitigated the environmental effects of the extinction event. The result was Patterson's Gap, a period in the earliest part of the Cenozoic of decreased acanthomorph diversity, although acanthomorphs diversified rapidly after the extinction. Teleost fish diversified explosively after the mass extinction, filling the niches left vacant by the extinction. Groups appearing in the Paleocene and Eocene epochs include billfish, tunas, eels, and flatfish. 2148: 2093: 1384: 1325:, which lived in freshwater and marine locations. Approximately 50% of crocodyliform representatives survived across the K–Pg boundary, the only apparent trend being that no large crocodiles survived. Crocodyliform survivability across the boundary may have resulted from their aquatic niche and ability to burrow, which reduced susceptibility to negative environmental effects at the boundary. Jouve and colleagues suggested in 2008 that juvenile marine crocodyliforms lived in freshwater environments as do modern marine 525: 430: 989: 2000:, as the source of the K–Pg boundary clay. Identified in 1990 based on work by geophysicist Glen Penfield in 1978, the crater is oval, with an average diameter of roughly 180 km (110 mi), about the size calculated by the Alvarez team. In March 2010, an international panel of 41 scientists reviewed 20 years of scientific literature and endorsed the asteroid hypothesis, specifically the Chicxulub impact, as the cause of the extinction, ruling out other theories such as massive 2538: 65: 2425:

Traps volcanism resulted in carbon dioxide emissions that increased the greenhouse effect when the dust and aerosols cleared from the atmosphere. Plant fossils record a 250 ppm increase in carbon dioxide concentrations across the K-Pg boundary likely attributable to Deccan Traps activity. The increased carbon dioxide emissions also caused acid rain, evidenced by increased mercury deposition due to increased solubility of mercury compounds in more acidic water.

1744: 16679: 2045: 803:. Major spatial differences existed in calcareous nannoplankton diversity patterns; in the Southern Hemisphere, the extinction was less severe and recovery occurred much faster than in the Northern Hemisphere. Following the extinction, survivor communities dominated for several hundred thousand years. The North Pacific acted as a diversity hotspot from which later nannoplankton communities radiated as they replaced survivor faunas across the globe. 76: 1428:), which both date from approximately 75 Ma, provides information on the changes in dinosaur populations over the last 10 million years of the Cretaceous. These fossil beds are geographically limited, covering only part of one continent. The middle–late Campanian formations show a greater diversity of dinosaurs than any other single group of rocks. The late Maastrichtian rocks contain the largest members of several major clades: 1900: 45: 985:), became extinct at the K–Pg boundary, with the gradual extinction of most inoceramid bivalves beginning well before the K–Pg boundary. Deposit feeders were the most common bivalves in the catastrophe's aftermath. Abundance was not a factor that affected whether a bivalve taxon went extinct, according to evidence from North America. Veneroid bivalves developed deeper burrowing habitats as the recovery from the crisis ensued. 2075: 861:

indicates substantial extinction of these species at the K–Pg boundary, and those who think the evidence supports a gradual extinction through the boundary. There is strong evidence that local conditions heavily influenced diversity changes in planktonic foraminifera. Low and mid-latitude communities of planktonic foraminifera experienced high extinction rates, while high latitude faunas were relatively unaffected.

1877: 16689: 1178:; therefore, some amphibians do seem to have become extinct at the boundary. The relatively low levels of extinction seen among amphibians probably reflect the low extinction rates seen in freshwater animals. Following the mass extinction, frogs radiated substantially, with 88% of modern anuran diversity being traced back to three lineages of frogs that evolved after the cataclysm. 1611:; this small size would have helped them find shelter in protected environments. It is postulated that some early monotremes, marsupials, and placentals were semiaquatic or burrowing, as there are multiple mammalian lineages with such habits today. Any burrowing or semiaquatic mammal would have had additional protection from K–Pg boundary environmental stresses. 1375:

groups, possibly due to direct competition, or they simply filled empty niches, but there is no correlation between pterosaur and avian diversities that are conclusive to a competition hypothesis, and small pterosaurs were present in the Late Cretaceous. At least some niches previously held by birds were reclaimed by pterosaurs prior to the K–Pg event.

1664:, that do not require photosynthesis and use nutrients from decaying vegetation. The dominance of fungal species lasted only a few years while the atmosphere cleared and plenty of organic matter to feed on was present. Once the atmosphere cleared photosynthetic organisms returned – initially ferns and other ground-level plants. 925:, extinction patterns were highly heterogeneous and cannot be neatly attributed to any particular factor. Decapods that inhabited the Western Interior Seaway were especially hard-hit, while other regions of the world's oceans were refugia that increased chances of survival into the Palaeocene. Among retroplumid crabs, the genus 10701: 1975:, but this was the first hard evidence, and since then, studies have continued to demonstrate elevated iridium levels in association with the K-Pg boundary. This hypothesis was viewed as radical when first proposed, but additional evidence soon emerged. The boundary clay was found to be full of minute 2439:

Combining these theories, some geophysical models suggest that the impact contributed to the Deccan Traps. These models, combined with high-precision radiometric dating, suggest that the Chicxulub impact could have triggered some of the largest Deccan eruptions, as well as eruptions at active volcano

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After the impact winter, the Earth entered a period of global warming as a result of the vapourisation of carbonates into carbon dioxide, whose long residence time in the atmosphere ensured significant warming would occur after more short-lived cooling gases dissipated. Carbon monoxide concentrations

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Scientists agree that all non-avian dinosaurs became extinct at the K–Pg boundary. The dinosaur fossil record has been interpreted to show both a decline in diversity and no decline in diversity during the last few million years of the Cretaceous, and it may be that the quality of the dinosaur fossil

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The extinction event produced major changes in Paleogene insect communities. Many groups of ants were present in the Cretaceous, but in the Eocene ants became dominant and diverse, with larger colonies. Butterflies diversified as well, perhaps to take the place of leaf-eating insects wiped out by the

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Clyde, William C.; Wilf, Peter; Iglesias, Ari; Slingerland, Rudy L.; Barnum, Timothy; Bijl, Peter K.; Bralower, Timothy J.; Brinkhuis, Henk; Comer, Emily E.; Huber, Brian T.; Ibañez-Mejia, Mauricio; Jicha, Brian R.; Krause, J. Marcelo; Schueth, Jonathan D.; Singer, Bradley S.; Raigemborn, María Sol;

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around the Chicxulub impact crater. The discoveries confirmed that the rock comprising the peak ring had been shocked by immense pressure and melted in just minutes from its usual state into its present form. Unlike sea-floor deposits, the peak ring was made of granite originating much deeper in the

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pollen grains, but the boundary layer contains little pollen and is dominated by fern spores. More usual pollen levels gradually resume above the boundary layer. This is reminiscent of areas blighted by modern volcanic eruptions, where the recovery is led by ferns, which are later replaced by larger

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MacLeod, N.; Rawson, P.F.; Forey, P.L.; Banner, F.T.; Boudagher-Fadel, M.K.; Bown, P.R.; Burnett, J.A.; Chambers, P.; Culver, S.; Evans, S.E.; Jeffery, C.; Kaminski, M.A.; Lord, A.R.; Milner, A.C.; Milner, A.R.; Morris, N.; Owen, E.; Rosen, B.R.; Smith, A.B.; Taylor, P.D.; Urquhart, E.; Young, J.R.

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Evidence for extinctions caused by the Deccan Traps includes the reduction in diversity of marine life when the climate near the K–Pg boundary increased in temperature. The temperature increased about three to four degrees very rapidly between 65.4 and 65.2 million years ago, which is very near the

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While it appears that many fungi were wiped out at the K-Pg boundary, there is some evidence that some fungal species thrived in the years after the extinction event. Microfossils from that period indicate a great increase in fungal spores, long before the resumption of plentiful fern spores in the

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comprising lizards and snakes first diversified during the Jurassic and continued to diversify throughout the Cretaceous. They are currently the most successful and diverse group of living reptiles, with more than 10,000 extant species. The only major group of terrestrial lizards to go extinct

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and are represented by living species. Analysis of turtle survivorship in the Hell Creek Formation shows a minimum of 75% of turtle species survived. Following the extinction event, turtle diversity exceeded pre-extinction levels in the Danian of North America, although in South America it remained

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area, the most species-rich part of the sea, and therefore could have been enough to cause a marine mass extinction. This change would not have caused the extinction of the ammonites. The regression would also have caused climate changes, partly by disrupting winds and ocean currents and partly by

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effect. If widespread fires occurred this would have exterminated the most vulnerable organisms that survived the period immediately after the impact. Experimental analysis suggests that any impact-induced wildfires were insufficient on their own to cause plant extinctions, and much of the thermal

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matching those of the Chicxulub impact event. Some researchers question the interpretation of the findings at the site or are skeptical of the team leader, Robert DePalma, who had not yet received his Ph.D. in geology at the time of the discovery and whose commercial activities have been regarded

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bird relatives coexisted with non-avian dinosaurs. Large collections of bird fossils representing a range of different species provide definitive evidence for the persistence of archaic birds to within 300,000 years of the K–Pg boundary. The absence of these birds in the Paleogene is evidence

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in Alberta, Canada, supports the gradual extinction of non-avian dinosaurs; during the last 10 million years of the Cretaceous layers there, the number of dinosaur species seems to have decreased from about 45 to approximately 12. Other scientists have made the same assessment following their

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and a basal toothed taxon of uncertain affinities, though they are represented by fragmentary remains that are difficult to assign to any given group. While this was occurring, modern birds were undergoing diversification; traditionally it was thought that they replaced archaic birds and pterosaur

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from fourteen sites in North America was used as a proxy for insect diversity across the K–Pg boundary and analyzed to determine the rate of extinction. Researchers found that Cretaceous sites, prior to the extinction event, had rich plant and insect-feeding diversity. During the early Paleocene,

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The Deccan Traps could have caused extinction through several mechanisms, including the release of dust and sulfuric aerosols into the air, which might have blocked sunlight and thereby reduced photosynthesis in plants. In addition, the latest Cretaceous saw a rise in global temperatures; Deccan

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has been estimated at more than 100 m (330 ft) tall, as the asteroid fell into relatively shallow seas; in deep seas it would have been 4.6 km (2.9 mi) tall. Fossiliferous sedimentary rocks deposited during the K–Pg impact have been found in the Gulf of Mexico area, including

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mammals occurred after approximately 185,000 years, and no more than 570,000 years, "indicating rapid rates of biotic extinction and initial recovery in the Denver Basin during this event." Analysis of the carbon cycle disruptions caused by the impact constrains them to an interval of just 5,000

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orders diversified soon after the K–Pg boundary. However, morphological diversification rates among eutherians after the extinction event were thrice those of before it. Also significant, within the mammalian genera, new species were approximately 9.1% larger after the K–Pg boundary. After about

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After the K–Pg extinction, mammals evolved to fill the niches left vacant by the dinosaurs. Some research indicates that mammals did not explosively diversify across the K–Pg boundary, despite the ecological niches made available by the extinction of dinosaurs. Several mammalian orders have been

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Phytoplankton recovery in the early Paleocene provided the food source to support large benthic foraminiferal assemblages, which are mainly detritus-feeding. Ultimate recovery of the benthic populations occurred over several stages lasting several hundred thousand years into the early Paleocene.

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families and 13 batoid families thrived, of which 25 and 9, respectively, survived the K–T boundary event. Forty-seven of all neoselachian genera cross the K–T boundary, with 85% being sharks. Batoids display with 15%, a comparably low survival rate. Among elasmobranchs, those species that

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across the K–Pg boundary has been studied since the 1930s. Research spurred by the possibility of an impact event at the K–Pg boundary resulted in numerous publications detailing planktonic foraminiferal extinction at the boundary; there is ongoing debate between groups which think the evidence

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caused the extinction were usually linked to the view that the extinction was gradual, as the flood basalt events were thought to have started around 68 Mya and lasted more than 2 million years. The most recent evidence shows that the traps erupted over a period of only 800,000 years

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Plant fossils illustrate the reduction in plant species across the K–Pg boundary. There is overwhelming evidence of global disruption of plant communities at the K–Pg boundary. Extinctions are seen both in studies of fossil pollen, and fossil leaves. In North America, the data suggests massive

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Proponents of multiple causation view the suggested single causes as either too small to produce the vast scale of the extinction, or not likely to produce its observed taxonomic pattern. In a review article, J. David Archibald and David E. Fastovsky discussed a scenario combining three major

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along the Gulf Coast and the Caribbean provided more evidence, and suggested that the impact might have occurred nearby, as did the discovery that the K–Pg boundary became thicker in the southern United States, with meter-thick beds of debris occurring in northern New Mexico. A K-Pg boundary

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Ca values indicate that prior to the mass extinction, marine reptiles at the top of food webs were feeding on only one source of calcium, suggesting their populations exhibited heightened vulnerability to extinctions at the terminus of the Cretaceous. Along with the aforementioned mosasaurs,

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in the ocean is thought to have decreased. As the marine microbiota recovered, it is thought that increased speciation of benthic foraminifera resulted from the increase in food sources. In some areas, such as Texas, benthic foraminifera show no sign of any major extinction event, however.

9836:

Bertrand, Ornella C.; Shelley, Sarah L.; Williamson, Thomas E.; Wible, John R.; Chester, Stephen G. B.; Flynn, John J.; Holbrook, Luke T.; Lyson, Tyler R.; Meng, Jin; Miller, Ian M.; Püschel, Hans P.; Smith, Thierry; Spaulding, Michelle; Tseng, Z. Jack; Brusatte, Stephen L. (April 2022).

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biases and the sparsity of the continental fossil record. The results of this study, which were based on estimated real global biodiversity, showed that between 628 and 1,078 non-avian dinosaur species were alive at the end of the Cretaceous and underwent sudden extinction after the

12552:

Lawton, T. F.; Shipley, K. W.; Aschoff, J. L.; Giles, K. A.; Vega, F. J. (2005). "Basinward transport of Chicxulub ejecta by tsunami-induced backflow, La Popa basin, northeastern Mexico, and its implications for distribution of impact-related deposits flanking the Gulf of Mexico".

918:. Current research cannot ascertain whether the extinctions occurred prior to, or during, the boundary interval. Ostracods that were heavily sexually selected were more vulnerable to extinction, and ostracod sexual dimorphism was significantly rarer following the mass extinction. 1046:

that thrived in low-latitude, shallow-water environments during the late Cretaceous had the highest extinction rate. Mid-latitude, deep-water echinoderms were much less affected at the K–Pg boundary. The pattern of extinction points to habitat loss, specifically the drowning of

2518:, and extraterrestrial impact. In this scenario, terrestrial and marine communities were stressed by the changes in, and loss of, habitats. Dinosaurs, as the largest vertebrates, were the first affected by environmental changes, and their diversity declined. At the same time, 1407:

Whether the extinction occurred gradually or suddenly has been debated, as both views have support from the fossil record. A highly informative sequence of dinosaur-bearing rocks from the K–Pg boundary is found in western North America, particularly the late Maastrichtian-age

10805:

Depalma, Robert A.; Oleinik, Anton A.; Gurche, Loren P.; Burnham, David A.; Klingler, Jeremy J.; McKinney, Curtis J.; Cichocki, Frederick P.; Larson, Peter L.; Egerton, Victoria M.; Wogelius, Roy A.; Edwards, Nicholas P.; Bergmann, Uwe; Manning, Phillip L. (8 December 2021).

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Smit, Jan; Montanari, Alessandro; Swinburne, Nicola H.; Alvarez, Walter; Hildebrand, Alan R.; Margolis, Stanley V.; Claeys, Philippe; Lowrie, William; Asaro, Frank (1992). "Tektite-bearing, deep-water clastic unit at the Cretaceous-Tertiary boundary in northeastern Mexico".

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provide a fossil record, and not all dinoflagellate species have cyst-forming stages, which likely causes diversity to be underestimated. Recent studies indicate that there were no major shifts in dinoflagellates through the boundary layer. There were blooms of the taxa

2256:, which might have reduced sunlight reaching the Earth's surface by more than 50%. Fine silicate dust also contributed to the intense impact winter, as did soot from wildfires. The climatic forcing of this impact winter was about 100 times more potent than that of the 1690:

appears to have enhanced the ability of flowering plants to survive the extinction, probably because the additional copies of the genome such plants possessed allowed them to more readily adapt to the rapidly changing environmental conditions that followed the impact.

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Other crater-like topographic features have also been proposed as impact craters formed in connection with Cretaceous–Paleogene extinction. This suggests the possibility of near-simultaneous multiple impacts, perhaps from a fragmented asteroidal object similar to the

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Ten families of crocodilians or their close relatives are represented in the Maastrichtian fossil records, of which five died out prior to the K–Pg boundary. Five families have both Maastrichtian and Paleocene fossil representatives. All of the surviving families of

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Kaskes, P.; Goderis, S.; Belza, J.; Tack, P.; DePalma, R. A.; Smit, J.; Vincze, Laszlo; Vabgaecje, F.; Claeys, P. (2019). "Caught in amber: Geochemistry and petrography of uniquely preserved Chicxulub microtektites from the Tanis K-Pg site from North Dakota (USA)".

955:, which collapsed due to the events surrounding the K–Pg boundary, but the use of data from coral fossils to support K–Pg extinction and subsequent Paleocene recovery, must be weighed against the changes that occurred in coral ecosystems through the K–Pg boundary. 2789:

Jones, Heather L.; Westerhold, Thomas; Birch, Heather; Hull, Pincelli; Negra, M. Hédi; Röhl, Ursula; Sepúlveda, Julio; Vellekoop, Johan; Whiteside, Jessica H.; Alegret, Laia; Henehan, Michael; Robinson, Libby; Van Dijk, Joep; Bralower, Timothy (18 January 2023).

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probably died out long after the most recent fossil that has been found. Scientists have also found very few continuous beds of fossil-bearing rock that cover a time range from several million years before the K–Pg extinction to several million years after it.

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of asteroids. This link has been doubted, though not disproved, in part because of a lack of observations of the asteroid and its family. It was reported in 2009 that 298 Baptistina does not share the chemical signature of the K–Pg impactor. Further, a 2011

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Ferreira da Silva, Luiza Carine; Santos, Alessandra; Fauth, Gerson; Manríquez, Leslie Marcela Elizabeth; Kochhann, Karlos Guilherme Diemer; Do Monte Guerra, Rodrigo; Horodyski, Rodrigo Scalise; Villegas-Martín, Jorge; Ribeiro da Silva, Rafael (April 2023).

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survived; the exact reasons for this pattern are not known. Sebecids were large terrestrial predators, are known from the Eocene of Europe, and would survive in South America into the Miocene. Tethysuchians radiated explosively after the extinction event.

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deposits and sediments around the area of the Caribbean Sea and Gulf of Mexico, from the colossal waves created by the impact. These deposits have been identified in the La Popa basin in northeastern Mexico, platform carbonates in northeastern Brazil, in

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The extinction's rapidity is a controversial issue because some researchers think the extinction was the result of a sudden event, while others argue that it took place over a long period. The exact length of time is difficult to determine because of the

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The river bed at the Moody Creek Mine, 7 Mile Creek / Waimatuku, Dunollie, New Zealand contains evidence of a devastating event on terrestrial plant communities at the Cretaceous–Paleogene boundary, confirming the severity and global nature of the

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Ocampo, A.; Vajda, V.; Buffetaut, E. (2006). "Unravelling the Cretaceous–Paleogene (K–T) turnover, evidence from flora, fauna and geology in biological processes associated with impact events". In Cockell, C.; Gilmour, I.; Koeberl, C. (eds.).

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Arenillas, I.; Arz, J. A.; Molina, E.; Dupuis, C. (2000). "An independent test of planktic foraminiferal turnover across the Cretaceous/Paleogene (K/P) boundary at El Kef, Tunisia: Catastrophic mass extinction and possible survivorship".

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Ryan, M. J.; Russell, A. P.; Eberth, D. A.; Currie, P. J. (2001). "The taphonomy of a Centrosaurus (Ornithischia: Ceratopsidae) bone bed from the Dinosaur Park formation (Upper Campanian), Alberta, Canada, with comments on cranial ontogeny".

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Galeotti, S.; Bellagamba, M.; Kaminski, M. A.; Montanari, A. (2002). "Deep-sea benthic foraminiferal recolonisation following a volcaniclastic event in the lower Campanian of the Scaglia Rossa Formation (Umbria-Marche Basin, central Italy)".

1564:, for example, rapidly diversified in the early Paleogene and are believed to have convergently developed flightlessness at least three to six times, often fulfilling the niche space for large herbivores once occupied by non-avian dinosaurs. 2268:

dropped as much as 7 °C (13 °F) for decades after the impact. It would take at least ten years for such aerosols to dissipate, and would account for the extinction of plants and phytoplankton, and subsequently herbivores and their

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The release of large quantities of sulphur aerosols into the atmosphere as a consequence of the impact would also have caused acid rain. Oceans acidified as a result. This decrease in ocean pH would kill many organisms that grow shells of

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Timms, Nicholas E.; Kirkland, Christopher L.; Cavosie, Aaron J.; Rae, Auriol S.P.; Rickard, William D.A.; Evans, Noreen J.; Erickson, Timmons M.; Wittmann, Axel; Ferrière, Ludovic; Collins, Gareth S.; Gulick, Sean P.S. (15 July 2020).

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Labandeira, C. C.; Johnson, K. R.; et al. (2002). "Preliminary assessment of insect herbivory across the Cretaceous-Tertiary boundary: Major extinction and minimum rebound". In Hartman, J.H.; Johnson, K.R.; Nichols, D.J. (eds.).

8130: 3445:"The nastiest feud in science: A Princeton geologist has endured decades of ridicule for arguing that the fifth extinction was caused not by an asteroid but by a series of colossal volcanic eruptions. But she's reopened that debate" 2522:

materials from volcanism cooled and dried areas of the globe. Then an impact event occurred, causing collapses in photosynthesis-based food chains, both in the already-stressed terrestrial food chains and in the marine food chains.

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across the K–Pg boundary, which provide good evidence of extinction patterns of these classes of marine vertebrates. While the deep-sea realm was able to remain seemingly unaffected, there was an equal loss between the open marine

8354:

Butler, Richard J.; Barrett, Paul M.; Nowbath, Stephen; Upchurch, Paul (2009). "Estimating the effects of sampling biases on pterosaur diversity patterns: Implications for hypotheses of bird / pterosaur competitive replacement".

2184:. The Chicxulub impact caused a global catastrophe. Some of the phenomena were brief occurrences immediately following the impact, but there were also long-term geochemical and climatic disruptions that devastated the ecology. 2452:

rock layers from various parts of the world, the later layers are terrestrial; earlier layers represent shorelines and the earliest layers represent seabeds. These layers do not show the tilting and distortion associated with

1988:"cocktail" of microfossils, lithic fragments, and impact-derived material deposited by gigantic sediment gravity flows was discovered in the Caribbean that served to demarcate the impact. Further research identified the giant 8708:

Rieraa, V.; Marmib, J.; Omsa, O.; Gomez, B. (March 2010). "Orientated plant fragments revealing tidal palaeocurrents in the Fumanya mudflat (Maastrichtian, southern Pyrenees): Insights in palaeogeographic reconstructions".

557:

becoming extinct during any given time interval. It does not represent all marine species, just those that are readily fossilized. The labels of the traditional "Big Five" extinction events and the more recently recognised

2163:

of non-avian dinosaurs and many other species on Earth. The impact spewed hundreds of billions of tons of sulfur into the atmosphere, producing a worldwide blackout and freezing temperatures which persisted for at least a

6040:

Ward, P. D.; Kennedy, W. J.; MacLeod, K. G.; Mount, J. F. (1991). "Ammonite and inoceramid bivalve extinction patterns in Cretaceous/Tertiary boundary sections of the Biscay region (southwestern France, northern Spain)".

11695:

Depalma, Robert A.; Smit, Jan; Burnham, David A.; Kuiper, Klaudia; Manning, Phillip L.; Oleinik, Anton; Larson, Peter; Maurrasse, Florentin J.; Vellekoop, Johan; Richards, Mark A.; Gurche, Loren; Alvarez, Walter (2019).

4602:"New age constraints for the Salamanca Formation and lower Río Chico Group in the western San Jorge Basin, Patagonia, Argentina: Implications for Cretaceous-Paleogene extinction recovery and land mammal age correlations" 9148:

Mitchell, K.J.; Llamas, B.; Soubrier, J.; Rawlence, N. J.; Worthy, T. H.; Wood, J.; Lee, M. S. Y.; Cooper, A. (2014). "Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution".

2236:

Aside from the hypothesized fire effects on reduction of insolation, the impact would have created a humongous dust cloud that blocked sunlight for up to a year, inhibiting photosynthesis. The asteroid hit an area of

10747:

During, Melanie A. D.; Smit, Jan; Voeten, Dennis F. A. E.; Berruyer, Camille; Tafforeau, Paul; Sanchez, Sophie; Stein, Koen H. W.; Verdegaal-Warmerdam, Suzan J. A.; Van Der Lubbe, Jeroen H. J. L. (23 February 2022).

5186:

MacLeod, N (1996). "Nature of the Cretaceous-Tertiary (K–T) planktonic foraminiferal record: Stratigraphic confidence intervals, Signor–Lipps effect, and patterns of survivorship". In MacLeod, N.; Keller, G. (eds.).

1135:

inhabited higher latitudes and lived pelagic lifestyles were more likely to survive, whereas epibenthic lifestyles and durophagy were strongly associated with the likelihood of perishing during the extinction event.

12181:

Majaess, D. J.; Higgins, D.; Molnar, L. A.; Haegert, M. J.; Lane, D. J.; Turner, D. G.; Nielsen, I. (February 2009). "New constraints on the asteroid 298 Baptistina, the alleged family member of the K/T impactor".

1572:

Mammalian species began diversifying approximately 30 million years prior to the K–Pg boundary. Diversification of mammals stalled across the boundary. All major Late Cretaceous mammalian lineages, including

4419:

Aberhan, M.; Weidemeyer, S.; Kieesling, W.; Scasso, R.A.; Medina, F.A. (2007). "Faunal evidence for reduced productivity and uncoordinated recovery in Southern Hemisphere Cretaceous-Paleogene boundary sections".

1162:

concluded that no species of amphibian became extinct. Yet there are several species of Maastrichtian amphibian, not included as part of this study, which are unknown from the Paleocene. These include the frog

13502: 13326: 12403: 11953: 11702: 10645: 10484: 9631: 6976: 6267: 5934: 4497:

García-Girón, Jorge; Chiarenza, Alfio Alessandro; Alahuhta, Janne; DeMar, David G.; Heino, Jani; Mannion, Philip D.; Williamson, Thomas E.; Wilson Mantilla, Gregory P.; Brusatte, Stephen L. (9 December 2022).

3739: 3673: 3597: 3348: 3208: 1559:

group in particular) appeared to radiate after the K–Pg boundary. The open niche space and relative scarcity of predators following the K-Pg extinction allowed for adaptive radiation of various avian groups.

2264:, the onset of global darkness would have reached its maximum in only a few weeks and likely lasted upwards of 2 years. Freezing temperatures probably lasted for at least three years. At Brazos section, the 1462:

of Europe in 2010 supports the view that dinosaurs there had great diversity until the asteroid impact, with more than 100 living species. More recent research indicates that this figure is obscured by

7826:"Polycotylidae (Sauropterygia, Plesiosauria) from the La Colonia Formation, Patagonia, Argentina: Phylogenetic affinities of Sulcusuchus erraini and the Late Cretaceous circum-pacific polycotylid diversity" 913:

that were prevalent in the upper Maastrichtian, left fossil deposits in a variety of locations. A review of these fossils shows that ostracod diversity was lower in the Paleocene than any other time in the

833:

times, and their mineral fossil skeletons can be tracked across the K–Pg boundary. There is no evidence of mass extinction of these organisms, and there is support for high productivity of these species in

9997:

Askin, R.A.; Jacobson, S.R. (1996). "Palynological change across the Cretaceous–Tertiary boundary on Seymour Island, Antarctica: environmental and depositional factors". In Keller, G.; MacLeod, N. (eds.).

2504:

However, sea level fall as a cause of the extinction event is contradicted by other evidence, namely that sections which show no sign of marine regression still show evidence of a major drop in diversity.

417:. The surviving group of dinosaurs were avians, a few species of ground and water fowl, which radiated into all modern species of birds. Among other groups, teleost fish and perhaps lizards also radiated. 1632:

700,000 years, some mammals had reached 50 kilos (110 pounds), a 100-fold increase over the weight of those which survived the extinction. It is thought that body sizes of placental mammalian survivors

2196:

deep-sea sediments, and in the form of the thickest-known layer of graded sand deposits, around 100 m (330 ft), in the Chicxulub crater itself, directly above the shocked granite ejecta. The

9258:

Bininda-Emonds, O. R.; Cardillo M.; Jones, K. E., MacPhee, R. D.; Beck, R. M.; Grenyer, R.; Price, S. A.; Vos, R. A.; Gittleman, J. L.; Purvis, A. (2007). "The delayed rise of present-day mammals".

9364:

Goin, F. J.; Reguero, M. A.; Pascual, R.; von Koenigswald, W.; Woodburne, M. O.; Case, J. A.; Marenssi, S. A.; Vieytes, C.; Vizcaíno, S. F. (2006). "First gondwanatherian mammal from Antarctica".

5674:

Vescsei, A.; Moussavian, E. (1997). "Paleocene reefs on the Maiella Platform margin, Italy: An example of the effects of the cretaceous/tertiary boundary events on reefs and carbonate platforms".

15238: 2735: 578:

The K–Pg extinction event was severe, global, rapid, and selective, eliminating a vast number of species. Based on marine fossils, it is estimated that 75% or more of all species became extinct.

2004:. They had determined that a 10-to-15-kilometer (6 to 9 mi) asteroid hurtled into Earth at Chicxulub on Mexico's Yucatán Peninsula. Additional evidence for the impact event is found at the 1358:, were definitely present in the Maastrichtian, and they likely became extinct at the K–Pg boundary. Several other pterosaur lineages may have been present during the Maastrichtian, such as the 4924: 2127:. He further posits that the mass extinction occurred within 32,000 years of this date. The dating of hydrothermally altered structures around the crater is consistent with this timeline. 13769:"Direct measurements of chemical composition of shock-induced gases from calcite: an intense global warming after the Chicxulub impact due to the indirect greenhouse effect of carbon monoxide" 2413:

The Deccan Traps, which erupted close to the boundary between the Mesozoic and Cenozoic, have been cited as an alternate explanation for the mass extinction. Before 2000, arguments that the

3070: 6841:

Alfaro, Michael E.; Faircloth, Brant C.; Harrington, Richard C.; Sorenson, Laurie; Friedman, Matt; Thacker, Christine E.; Oliveros, Carl H.; Černý, David; Near, Thomas J. (12 March 2018).

13265: 1680:

angiosperm plants. In North American terrestrial sequences, the extinction event is best represented by the marked discrepancy between the rich and relatively abundant late-Maastrichtian

6897:

Archibald, J. D.; Bryant, L. J. (1990). "Differential Cretaceous–Tertiary extinction of nonmarine vertebrates; evidence from northeastern Montana". In Sharpton, V.L.; Ward, P.D. (eds.).

2205:-type ecosystem, indicating that water in the Gulf of Mexico sloshed back and forth repeatedly after the impact; dead fish left in these shallow waters were not disturbed by scavengers. 939:

genera failed to cross the K–Pg boundary into the Paleocene. Further analysis of the coral extinctions shows that approximately 98% of colonial species, ones that inhabit warm, shallow

9972:

Johnson, K.R.; Hickey, L.J. (1991). "Megafloral change across the Cretaceous Tertiary boundary in the northern Great Plains and Rocky Mountains". In Sharpton, V.I.; Ward, P.D. (eds.).

14320:

Keller, G.; Adatte, T.; Gardin, S.; Bartolini, A.; Bajpai, S. (2008). "Main Deccan volcanism phase ends near the K–T boundary: Evidence from the Krishna-Godavari Basin, SE India".

9212:

Yonezawa, Takahiro; Segawa, Takahiro; Mori, Hiroshi; Campos, Paula F.; Hongoh, Yuichi; Endo, Hideki; Akiyoshi, Ayumi; Kohno, Naoki; Nishida, Shin; Wu, Jiaqi; Jin, Haofei (2017).

9573:

Shupinski, Alex B.; Wagner, Peter J.; Smith, Felisa A.; Lyons, S. Kathleen (3 July 2024). "Unique functional diversity during early Cenozoic mammal radiation of North America".

15672: 2585: 11184:

Renne, Paul R.; Deino, Alan L.; Hilgen, Frederik J.; Kuiper, Klaudia F.; Mark, Darren F.; Mitchell, William S.; Morgan, Leah E.; Mundil, Roland; Smit, Jan (8 February 2013).

2791: 13320:

Lyons, Shelby L.; Karp, Allison T.; Bralower, Timothy J.; Grice, Kliti; Schaefer, Bettina; Gulick, Sean P. S.; Morgan, Joanna V.; Freeman, Katherine H. (28 September 2020).

2139:(WISE) study of reflected light from the asteroids of the family estimated their break-up at 80 Ma, giving them insufficient time to shift orbits and impact Earth by 66 Ma. 2104:

Some critics of the impact theory have put forward that the impact precedes the mass extinction by about 300,000 years and thus was not its cause. However, in a 2013 paper,

2792:"Stratigraphy of the Cretaceous/Paleogene (K/Pg) boundary at the Global Stratotype Section and Point (GSSP) in El Kef, Tunisia: New insights from the El Kef Coring Project" 12221:

Reddy, V.; Emery, J. P.; Gaffey, M. J.; Bottke, W. F.; Cramer, A.; Kelley, M. S. (December 2009). "Composition of 298 Baptistina: Implications for the K/T impactor link".

8746:

le Loeuff, J. (2012). "Paleobiogeography and biodiversity of Late Maastrichtian dinosaurs: How many dinosaur species became extinct at the Cretaceous-Tertiary boundary?".

2083: 1971:. Because of this, the Alvarez team suggested that an asteroid struck the Earth at the time of the K–Pg boundary. There were earlier speculations on the possibility of an 11012:"An asteroid killed dinosaurs in spring—which might explain why mammals survived – New study sheds light on why species extinction was so selective after the K-Pg impact" 13195:

Senel, Cem Berk; Kaskes, Pim; Temel, Orkun; Vellekoop, Johan; Goderis, Steven; DePalma, Robert; Prins, Maarten A.; Claeys, Philippe; Karatekin, Özgür (30 October 2023).

8177:

Company, J.; Ruiz-Omeñaca, J. I.; Pereda Suberbiola, X. (1999). "A long-necked pterosaur (Pterodactyloidea, Azhdarchidae) from the upper Cretaceous of Valencia, Spain".

1675:. Just two species of fern appear to have dominated the landscape for centuries after the event. In the sediments below the K–Pg boundary the dominant plant remains are 11647:

Stöffler, Dieter; Artemieva, Natalya A.; Ivanov, Boris A.; Hecht, Lutz; Kenkmann, Thomas; Schmitt, Ralf Thomas; Tagle, Roald Alberto; Wittmann, Axel (26 January 2010).

5436:

Brouwers, E. M.; de Deckker, P. (1993). "Late Maastrichtian and Danian Ostracode Faunas from Northern Alaska: Reconstructions of Environment and Paleogeography".

3308:"The dinosaur-killing asteroid acidified the ocean in a flash: the Chicxulub event was as damaging to life in the oceans as it was to creatures on land, a study shows" 12627:

Norris, R. D.; Firth, J.; Blusztajn, J. S. & Ravizza, G. (2000). "Mass failure of the North Atlantic margin triggered by the Cretaceous-Paleogene bolide impact".

8819:

Sloan, R. E.; Rigby, K.; van Valen, L. M.; Gabriel, Diane (1986). "Gradual dinosaur extinction and simultaneous ungulate radiation in the Hell Creek formation".

2489:

that ten million years before had been host to diverse communities such as are found in rocks of the Dinosaur Park Formation. Another consequence was an expansion of

5717:

Rosen, B. R.; Turnšek, D. (1989). Jell A; Pickett JW (eds.). "Extinction patterns and biogeography of scleractinian corals across the Cretaceous/Tertiary boundary".

3454: 9439: 6675:

Cione, Alberto L.; Santillana, Sergio; Gouiric-Cavalli, Soledad; Acosta Hospitaleche, Carolina; Gelfo, Javier N.; López, Guillermo M.; Reguero, Marcelo (May 2018).

6630:

Zinsmeister, W. J. (1 May 1998). "Discovery of fish mortality horizon at the K–T boundary on Seymour Island: Re-evaluation of events at the end of the Cretaceous".

6081:

Harries, P. J.; Johnson, K. R.; Cobban, W. A.; Nichols, D.J. (2002). "Marine Cretaceous-Tertiary boundary section in southwestern South Dakota: Comment and reply".

3266:

Hildebrand, A. R.; Penfield, G. T.; et al. (1991). "Chicxulub crater: a possible Cretaceous/Tertiary boundary impact crater on the Yucatán peninsula, Mexico".

2067: 1503:(about 1 million years after the K–Pg extinction event). If their existence past the K–Pg boundary can be confirmed, these hadrosaurids would be considered a 307:. The fact that the extinctions occurred simultaneously provides strong evidence that they were caused by the asteroid. A 2016 drilling project into the Chicxulub 13590: 13767:

Kawaragi, Ko; Sekine, Yasuhito; Kadono, Toshihiko; Sugita, Seiji; Ohno, Sohsuke; Ishibashi, Ko; Kurosawa, Kosuke; Matsui, Takafumi; Ikeda, Susumu (30 May 2009).

12184: 12065: 10029: 9692: 9575: 5995: 1815:

The sedimentation rate and thickness of K–Pg clay from three sites suggest rapid extinction, perhaps over a period of less than 10,000 years. At one site in the

12324: 8402:"Does morphology reflect osteohistology-based ontogeny? A case study of Late Cretaceous pterosaur jaw symphyses from Hungary reveals hidden taxonomic diversity" 1786:

assumptions" for the June dating have since all been refuted. Another modern study opted for the spring–summer range. A study of fossilized fish bones found at

389:, which became extinct), and many species of plankton. It is estimated that 75% or more of all species on Earth vanished. However, the extinction also provided 102:

a few kilometers across colliding with the Earth. Such an impact can release the equivalent energy of several million nuclear weapons detonating simultaneously;

9919:

Vajda, Vivi; Raine, J. Ian; Hollis, Christopher J. (2001). "Indication of global deforestation at the Cretaceous–Tertiary boundary by New Zealand fern spike".

6799:"The Cretaceous–Paleogene transition in spiny-rayed fishes: surveying "Patterson's Gap" in the acanthomorph skeletal record André Dumont medalist lecture 2018" 5411:

Coles, G. P.; Ayress, M. A.; Whatley, R. C. (1990). "A comparison of North Atlantic and 20 Pacific deep-sea Ostracoda". In Whatley, R. C.; Maybury, C. (eds.).

8025:"Phylogenetic structure of the extinction and biotic factors explaining differential survival of terrestrial notosuchians at the Cretaceous–Palaeogene crisis" 4601: 8881:. International Conference on Catastrophic Events and Mass Extinctions: Impacts and Beyond, 9–12 July 2000. Vol. 1053. Vienna, Austria. pp. 45–46. 2041:

with suspicion. Furthermore, indirect evidence of an asteroid impact as the cause of the mass extinction comes from patterns of turnover in marine plankton.

14624:

Sial, A. N.; Lacerda, L. D.; Ferreira, V. P.; Frei, R.; Marquillas, R. A.; Barbosa, J. A.; Gaucher, C.; Windmöller, C. C.; Pereira, N. S. (1 October 2013).

6739: 5139: 3133: 2448:

There is clear evidence that sea levels fell in the final stage of the Cretaceous by more than at any other time in the Mesozoic era. In some Maastrichtian

1333:

became extinct; freshwater environments were not so strongly affected by the K–Pg extinction event as marine environments were. Among the terrestrial clade

14357:

Callegaro, Sara; Baker, Don R.; Renne, Paul R.; Melluso, Leone; Geraki, Kalotina; Whitehouse, Martin J.; De Min, Angelo; Marzoli, Andrea (6 October 2023).

7720: 6175: 4361: 3317: 2032:. Tanis is an extraordinary and unique site because it appears to record the events from the first minutes until a few hours after the impact of the giant 14425: 7317:

Apesteguía, Sebastián; Novas, Fernando E. (2003). "Large Cretaceous sphenodontian from Patagonia provides insight into lepidosaur evolution in Gondwana".

4925:"Calcareous Nannofossils Across the Cretaceous–Tertiary Boundary at Brazos, Texas, U.S.A.: Extinction and Survivorship, Biostratigraphy, and Paleoecology" 2432:

In the years when the Deccan Traps hypothesis was linked to a slower extinction, Luis Alvarez (d. 1988) replied that paleontologists were being misled by

760:

during the Paleogene Period. After the K–Pg extinction event, biodiversity required substantial time to recover, despite the existence of abundant vacant

11790:

Tanis, a mixed marine-continental event deposit at the KPG Boundary in North Dakota caused by a seiche triggered by seismic waves of the Chicxulub Impact

7981:"The oldest African crocodylian: phylogeny, paleobiogeography, and differential survivorship of marine reptiles through the Cretaceous-Tertiary boundary" 3797:

The Hell Creek formation and the Cretaceous-Tertiary boundary in the northern Great Plains: An integrated continental record of the end of the Cretaceous

2212:, cooking exposed organisms. This is debated, with opponents arguing that local ferocious fires, probably limited to North America, fall short of global 15500: 11011: 4834:"The role of regional survivor incumbency in the evolutionary recovery of calcareous nannoplankton from the Cretaceous/Paleogene (K/Pg) mass extinction" 601:, but are unknown from the Cenozoic anywhere in the world. Similarly, fossil pollen shows devastation of the plant communities in areas as far apart as 397:—sudden and prolific divergence into new forms and species within the disrupted and emptied ecological niches. Mammals in particular diversified in the 16733: 15665: 11391:

Bohor, B. F.; Foord, E. E.; Modreski, P. J.; Triplehorn, D. M. (1984). "Mineralogic evidence for an impact event at the Cretaceous-Tertiary boundary".

10567:

Carvalho, Mónica R.; Jaramillo, Carlos; Parra, Felipe de la; Caballero-Rodríguez, Dayenari; Herrera, Fabiany; Wing, Scott; et al. (2 April 2021).

12681: 11649:"Origin and emplacement of the impact formations at Chicxulub, Mexico, as revealed by the ICDP deep drilling at Yaxcopoil-1 and by numerical modeling" 7031:

Evans, Susan E.; Klembara, Jozef (2005). "A choristoderan reptile (Reptilia: Diapsida) from the Lower Miocene of northwest Bohemia (Czech Republic)".

6199:"A 104-Ma record of deep-sea Atelostomata (Holasterioda, Spatangoida, irregular echinoids) – a story of persistence, food availability and a big bang" 14956: 14722: 14630: 14489: 14278: 13897: 12826: 8711: 8595: 6461: 6381: 5218: 4248:

Wilf, P.; Johnson, K.R. (2004). "Land plant extinction at the end of the Cretaceous: A quantitative analysis of the North Dakota megafloral record".

2855: 1597:

survived the K–Pg extinction event, although they suffered losses. In particular, metatherians largely disappeared from North America, and the Asian

1507:. The scientific consensus is that these fossils were eroded from their original locations and then re-buried in much later sediments (also known as 1064:

flora were relatively diverse with little predation from insects, even 1.7 million years after the extinction event. Studies of the size of the

11038:

Signor, Philip W. III; Lipps, Jere H. (1982). "Sampling bias, gradual extinction patterns, and catastrophes in the fossil record". In Silver, L.T.;

10456: 9311: 8296: 5721:. Proceedings of the Fifth International Symposium on Fossil Cnidaria including Archaeocyatha and Spongiomorphs (8). Brisbane, Queensland: 355–370. 4460:

Sheehan, Peter M.; Fastovsky, D. E. (1992). "Major extinctions of land-dwelling vertebrates at the Cretaceous-Tertiary boundary, eastern Montana".

2557: 3062: 15389: 3913: 14803: 12869: 11821: 8228: 6119: 16606: 12128:

Bottke, W. F.; Vokrouhlický, D.; Nesvorný, D. (September 2007). "An asteroid breakup 160 Myr ago as the probable source of the K/T impactor".

8916: 6459:

Kriwet, Jürgen; Benton, Michael J. (2004). "Neoselachian (Chondrichthyes, Elasmobranchii) Diversity across the Cretaceous–Tertiary Boundary".

5481:

Martins, Maria João Fernandes; Hunt, Gene; Thompson, Carmi Milagros; Lockwood, Rowan; Swaddle, John P.; Puckett, T. Markham (26 August 2020).

1484:

up to 1.3 m (4 ft 3.2 in) above and 40,000 years later than the K–Pg boundary. Pollen samples recovered near a fossilized

15658: 14952:"Coastal ecosystem responses to late stage Deccan Trap volcanism: the post K–T boundary (Danian) palynofacies of Mumbai (Bombay), west India" 13979: 12789: 7161: 12944:"An experimental assessment of the ignition of forest fuels by the thermal pulse generated by the Cretaceous–Palaeogene impact at Chicxulub" 10920: 10025:"No post-Cretaceous ecosystem depression in European forests? Rich insect-feeding damage on diverse middle Palaeocene plants, Menat, France" 4928: 12762: 12284: 9075: 8074:

Martin, Jeremy E.; Pochat-Cottilloux, Yohan; Laurent, Yves; Perrier, Vincent; Robert, Emmanuel; Antoine, Pierre-Olivier (28 October 2022).

6322:

Wilf, P.; Labandeira, C. C.; Johnson, K. R.; Ellis, B. (2006). "Decoupled plant and insect diversity after the end-Cretaceous extinction".

4880:

Gedl, P. (2004). "Dinoflagellate cyst record of the deep-sea Cretaceous-Tertiary boundary at Uzgru, Carpathian Mountains, Czech Republic".

753: 13158:

Ohno, S.; et al. (2014). "Production of sulphate-rich vapour during the Chicxulub impact and implications for ocean acidification".

6972:"Phylogenomics reveals rapid, simultaneous diversification of three major clades of Gondwanan frogs at the Cretaceous–Paleogene boundary" 2660:

Shocked minerals have their internal structure deformed, and are created by intense pressures as in nuclear blasts and meteorite impacts.

2568: 17: 8950:

Hou, L.; Martin, M.; Zhou, Z.; Feduccia, A. (1996). "Early Adaptive Radiation of Birds: Evidence from Fossils from Northeastern China".

1733:

would not need sunlight, allowing them to survive during a period when the atmosphere was likely clogged with dust and sulfur aerosols.

16718: 16663: 13001: 11501:

Bourgeois, J.; Hansen, T. A.; Wiberg, P. A.; Kauffman, E. G. (1988). "A tsunami deposit at the Cretaceous-Tertiary boundary in Texas".

11067: 4741: 2705: 2461:, a drop in sea level. There is no direct evidence for the cause of the regression, but the currently accepted explanation is that the 1158:

There is limited evidence for extinction of amphibians at the K–Pg boundary. A study of fossil vertebrates across the K–Pg boundary in

795:

deposits for which the Cretaceous is named. The turnover in this group is clearly marked at the species level. Statistical analysis of

271:

10 to 15 km (6 to 9 mi) wide, 66 million years ago, which devastated the global environment, mainly through a lingering

11903:"Benthic foraminiferal turnover across the Cretaceous/Paleogene boundary at Agost (southeastern Spain): paleoenvironmental inferences" 8890: 7663:

Martin, Jeremy E.; Vincent, Peggy; Tacail, Théo; Khaldoune, Fatima; Jourani, Essaid; Bardet, Nathalie; Balter, Vincent (5 June 2017).

2159:. The aftermath of this immense asteroid collision, which occurred approximately 66 million years ago, is believed to have caused the 244:, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows unusually high levels of the metal 15191:"Extended Cretaceous/Tertiary boundary extinctions and delayed population change in planktonic foraminifera from Brazos River, Texas" 13938: 12008:

Keller, Gerta; Adatte, Thierry; Stinnesbeck, Wolfgang; STüBEN, Doris; Berner, Zsolt; Kramar, Utz; Harting, Markus (26 January 2010).

7564:

Klein, Catherine G.; Pisani, Davide; Field, Daniel J.; Lakin, Rebecca; Wills, Matthew A.; Longrich, Nicholas R. (14 September 2021).

5827:

Marshall, C. R.; Ward, P. D. (1996). "Sudden and Gradual Molluscan Extinctions in the Latest Cretaceous of Western European Tethys".

5483:"Shifts in sexual dimorphism across a mass extinction in ostracods: implications for sexual selection as a factor in extinction risk" 4162:

Weishampel, D. B.; Barrett, P. M. (2004). "Dinosaur distribution". In Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (eds.).

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Irizarry, Kayla M.; Witts, James T.; Garb, Matthew P.; Rashkova, Anastasia; Landman, Neil H.; Patzkowsky, Mark E. (15 January 2023).

2181: 1496: 799:

losses at this time suggests that the decrease in diversity was caused more by a sharp increase in extinctions than by a decrease in

10372:

Field, Daniel J.; Bercovici, Antoine; Berv, Jacob S.; Dunn, Regan; Fastovsky, David E.; Lyson, Tyler R.; et al. (24 May 2018).

6970:

Feng, Yan-Jie; Blackburn, David C.; Liang, Dan; Hillis, David M.; Wake, David B.; Cannatella, David C.; Zhang, Peng (18 July 2017).

5777:

MacLeod, K. G. (1994). "Extinction of Inoceramid Bivalves in Maastrichtian Strata of the Bay of Biscay Region of France and Spain".

16488: 15820: 13821: 13381:

Kaiho, Kunio; Oshima, Naga; Adachi, Kouji; Adachi, Yukimasa; Mizukami, Takuya; Fujibayashi, Megumu; Saito, Ryosuke (14 July 2016).

4666:

Pospichal, J. J. (1996). "Calcareous nannofossils and clastic sediments at the Cretaceous–Tertiary boundary, northeastern Mexico".

2648: 2314:

and methane concentrations. The impact's injection of water vapour into the atmosphere also produced major climatic perturbations.

1051:, the shallow-water reefs in existence at that time, by the extinction event. Atelostomatans were affected by the Lilliput effect. 14485:"Integrated Paleocene calcareous plankton magnetobiochronology and stable isotope stratigraphy: DSDP Site 384 (NW Atlantic Ocean)" 3406:(2012). "The Cretaceous–Tertiary mass extinction, Chicxulub impact, and Deccan volcanism. Earth and life". In Talent, John (ed.). 3103: 2911:"High-latitude Cretaceous–Paleogene transition: New paleoenvironmental and paleoclimatic insights from Seymour Island, Antarctica" 16738: 16450: 10136: 10088: 9808: 7125: 5882:"The first 2 million years after the Cretaceous-Tertiary boundary in east Texas: rate and paleoecology of the molluscan recovery" 11143:"Direct high-precision U–Pb geochronology of the end-Cretaceous extinction and calibration of Paleocene astronomical timescales" 10639:

Visscher, H.; Brinkhuis, H.; Dilcher, D. L.; Elsik, W. C.; Eshet, Y.; Looy, C. V.; Rampino, M. R.; Traverse, A. (5 March 1996).

1195:(a group of semi-aquatic diapsids of uncertain position) survived across the K–Pg boundary subsequently becoming extinct in the 342:, and sea level change. However, in January 2020, scientists reported that climate-modeling of the extinction event favored the 16590: 16435: 15882: 15101: 12942:

Belcher, Claire M.; Hadden, Rory M.; Rein, Guillermo; Morgan, Joanna V.; Artemieva, Natalia; Goldin, Tamara (22 January 2015).

12462: 9326: 6747: 5310:"The Cretaceous–Paleogene (K–P) boundary at Brazos, Texas: Sequence stratigraphy, depositional events and the Chicxulub impact" 5144: 4606: 4209: 2796: 2591: 488: 14224:

Courtillot, Vincent; Besse, Jean; Vandamme, Didier; Montigny, Raymond; Jaeger, Jean-Jacques; Cappetta, Henri (November 1986).

6949:

Gardner, J. D. (2000). "Albanerpetontid amphibians from the upper Cretaceous (Campanian and Maastrichtian) of North America".

5636:"Costacopluma (Decapoda: Brachyura: Retroplumidae) from the Maastrichtian and Paleocene of Senegal: A survivor of K/Pg events" 2851:"Faunal and stratigraphic analysis of the basal Cretaceous-Paleogene (K-Pg) boundary event deposits, Brazos River, Texas, USA" 1220:

species passed through the K–Pg boundary. All six turtle families in existence at the end of the Cretaceous survived into the

16548: 16430: 15870: 15596: 15471: 15195: 14875: 14037: 13880: 13054: 12824:

Kring, David A. (2007). "The Chicxulub impact event and its environmental consequences at the Cretaceous-Tertiary boundary".

12675: 12529: 11053: 10007: 9981: 9416: 8692: 8573: 8528: 7377: 7173: 6914: 6505: 6440: 6197:

Wiese, Frank; Schlüter, Nils; Zirkel, Jessica; Herrle, Jens O.; Friedrich, Oliver (9 August 2023). Carnevale, Giorgio (ed.).

5420: 5196: 5016: 4179: 3804: 3427: 2770: 2745: 2689: 2579: 1737: 644:-eaters survived the extinction event, perhaps because of the increased availability of their food sources. Neither strictly 495: 14891:

Sprain, Courtney J.; Renne, Paul R.; Vanderkluysen, Loÿc; Pande, Kanchan; Self, Stephen; Mittal, Tushar (22 February 2019).

14766:"Extinction, survivorship and evolution of planktic foraminifera across the Cretaceous/Tertiary boundary at El Kef, Tunisia" 9688:"Eutherians experienced elevated evolutionary rates in the immediate aftermath of the Cretaceous–Palaeogene mass extinction" 2421:

spanning the K–Pg boundary, and therefore may be responsible for the extinction and the delayed biotic recovery thereafter.

1948: 756:. The elimination of dominant Cretaceous groups allowed other organisms to take their place, causing a remarkable amount of 16713: 16188: 11556:"The Cretaceous-Tertiary boundary cocktail: Chicxulub impact triggers margin collapse and extensive sediment gravity flows" 5881: 7875:"Extinction of fish-shaped marine reptiles associated with reduced evolutionary rates and global environmental volatility" 4113:"Explosive morphological diversification of spiny-finned teleost fishes in the aftermath of the end-Cretaceous extinction" 3444: 1943:

many times greater than normal (30, 160, and 20 times in three sections originally studied). Iridium is extremely rare in

16748: 16621: 16370: 14433: 14322: 14230: 14059: 13773: 13717: 13669: 13621: 11147: 9433: 8454:"Late Maastrichtian pterosaurs from North Africa and mass extinction of Pterosauria at the Cretaceous-Paleogene boundary" 5262:"Comparative biogeographic analysis of planktic foraminiferal survivorship across the Cretaceous/Tertiary (K/T) boundary" 3480: 2136: 10423: 943:

waters, became extinct. The solitary corals, which generally do not form reefs and inhabit colder and deeper (below the

16763: 16543: 15760: 14802:

Zhang, Laiming; Wang, Chengshan; Wignall, Paul B.; Kluge, Tobias; Wan, Xiaoqiao; Wang, Qian; Gao, Yuan (1 March 2018).

13580: 12463:"Baby, it's cold outside: Climate model simulations of the effects of the asteroid impact at the end of the Cretaceous" 12223: 12014: 11653: 8875:

Compelling new evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone San Juan Basin, New Mexico and Colorado, USA

7988: 7033: 6521:

Noubhani, Abdelmajid (2010). "The Selachians' faunas of the Moroccan phosphate deposits and the K-T mass extinctions".

4117: 620:

Despite the event's severity, there was significant variability in the rate of extinction between and within different

14804:"Deccan volcanism caused coupled pCO2 and terrestrial temperature rises, and pre-impact extinctions in northern China" 12057: 7212:"Tracing the patterns of non-marine turtle richness from the Triassic to the Palaeogene: from origin to global spread" 5991:"The K/T event and infaunality: morphological and ecological patterns of extinction and recovery in veneroid bivalves" 5540:"Temporal shifts in ostracode sexual dimorphism from the Late Cretaceous to the late Eocene of the U.S. Coastal Plain" 5140:"How complete are Cretaceous /Tertiary boundary sections? A chronostratigraphic estimate based on graphic correlation" 2245:

rock containing a large amount of combustible hydrocarbons and sulfur, much of which was vaporized, thereby injecting

1539:. Several analyses of bird fossils show divergence of species prior to the K–Pg boundary, and that duck, chicken, and 16508: 15784: 15258: 14626:"Mercury as a proxy for volcanic activity during extreme environmental turnover: The Cretaceous–Paleogene transition" 13873:

The Ends of the World: Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth's Past Mass Extinctions

13557:

Hand, Eric (17 November 2016). "Updated: Drilling of dinosaur-killing impact crater explains buried circular hills".

12948: 12312: 11298:

Smit, J.; Klaver, J. (1981). "Sanidine spherules at the Cretaceous-Tertiary boundary indicate a large impact event".

8076:"Anatomy and phylogeny of an exceptionally large sebecid (Crocodylomorpha) from the middle Eocene of southern France" 6176:"Variation in echinoid biodiversity during the Cenomanian-early Turonian transgressive episode in Charentes (France)" 6118:

Iba, Yasuhiro; Mutterlose, Jörg; Tanabe, Kazushige; Sano, Shin-ichi; Misaki, Akihiro; Terabe, Kazunobu (1 May 2011).

4946: 4317: 1888: 1858: 1672: 1458:, which suggests food was plentiful immediately prior to the extinction. A study of 29 fossil sites in Catalan 241: 11807:

Life after impact: A remarkable mammal burrow from the Chicxulub aftermath in the Hell Creek Formation, North Dakota

7805:

O'Keefe, F. R. (2001). "A cladistic analysis and taxonomic revision of the Plesiosauria (Reptilia: Sauropterygia)".

7625:"An early Eocene pan-gekkotan from France could represent an extra squamate group that survived the K-Pg extinction" 7210:

Cleary, Terri J.; Benson, Roger B. J.; Holroyd, Patricia A.; Barrett, Paul M. (10 May 2020). Mannion, Philip (ed.).

868:

foraminifera became extinct during the event, presumably because they depend on organic debris for nutrients, while

532: 437: 16642: 16611: 15808: 15796: 5384:

Kuhnt, W.; Collins, E. S. (1996). "8. Cretaceous to Paleogene benthic foraminifers from the Iberia abyssal plain".

5214:"The Cretaceous/Tertiary boundary stratotype section at El Kef, Tunisia: how catastrophic was the mass extinction?" 1241:, had begun to decline by the mid-Cretaceous, although they remained successful in the Late Cretaceous of southern 559: 502: 339: 11141:

Clyde, William C.; Ramezani, Jahandar; Johnson, Kirk R.; Bowring, Samuel A.; Jones, Matthew M. (15 October 2016).

9796: 1827:

lasted approximately 1,000 years, and no more than 71,000 years; at the same location, the earliest appearance of

1762:

the extinction-associated freezing to early June. A later study shifted the dating to spring season, based on the

16420: 16317: 15846: 15322:"End-Cretaceous extinction in Antarctica linked to both Deccan volcanism and meteorite impact via climate change" 13617:"The impact of the Cretaceous/Tertiary bolide on evaporite terrane and generation of major sulfuric acid aerosol" 12897: 12355: 12094: 9435:

The Extinction of the Multituberculates Outside North America: a Global Approach to Testing the Competition Model

8319: 8259: 7715: 7517:"A new polyglyphanodontian lizard with a complete lower temporal bar from the Upper Cretaceous of southern China" 7260:"Surviving the Cretaceous-Paleogene mass extinction event: A terrestrial stem turtle in the Cenozoic of Laurasia" 6780: 6677:"Before and after the K/Pg extinction in West Antarctica: New marine fish records from Marambio (Seymour) Island" 5930:"Abundance not linked to survival across the end-Cretaceous mass extinction: Patterns in North American bivalves" 4784:

Jiang, Shijun; Bralower, Timothy J.; Patzkowsky, Mark E.; Kump, Lee R.; Schueth, Jonathan D. (28 February 2010).

3182: 2573: 2257: 2233:

radiation generated by the impact would have been absorbed by the atmosphere and ejecta in the lower atmosphere.

1468:

Cretaceous–Paleogene extinction event. Alternatively, interpretation based on the fossil-bearing rocks along the

516: 319:, the usual sulfate-containing sea floor rock in the region: the gypsum would have vaporized and dispersed as an 15167: 12727: 11947:

Keller, G.; Adatte, T.; Stinnesbeck, W.; Rebolledo-Vieyra, _; Fucugauchi, J. U.; Kramar, U.; Stüben, D. (2004).

11625: 11573: 11362: 10358: 8797: 7166:

Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas

7046: 6104: 6064: 6008: 5157: 4762: 4689: 4577: 4483: 4402: 4263: 4222: 3307: 3289: 903:

across the K–Pg boundary. The apparent rate is influenced by a lack of fossil records, rather than extinctions.

16723: 16297: 15243:

Global Catastrophes in Earth History; An Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality

14576:

Milligan, Joseph N.; Royer, Dana L.; Franks, Peter J.; Upchurch, Garland R.; McKee, Melissa L. (7 March 2019).

12650: 12320: 11343:

Olsson, Richard K.; Miller, Kenneth G.; Browning, James V.; Habib, Daniel; Sugarman, Peter J. (1 August 1997).

10480:"Plants with double genomes might have had a better chance to survive the Cretaceous-Tertiary extinction event" 10180:"Divergence rates of subviral pathogens of angiosperms abruptly decreased at the Cretaceous-Paleogene boundary" 10084:"Flora development in Northeastern Asia and Northern Alaska during the Cretaceous-Paleogene transitional epoch" 9974:

Global Catastrophes in Earth History: An interdisciplinary conference on impacts, volcanism, and mass mortality

8401: 6899:

Global Catastrophes in Earth History: an Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality

4204: 2328: 1667:

In some regions, the Paleocene recovery of plants began with recolonizations by fern species, represented as a

697:

than among animals living on or in the sea floor. Animals in the water column are almost entirely dependent on

14458: 9331:(Mammalia, Dryolestida) from the early Paleocene of Patagonia, a survival from a Mesozoic Gondwanan radiation" 8001: 5538:

Samuels-Fair, Maya; Martins, Maria João Fernandes; Lockwood, Rowan; Swaddle, John P.; Hunt, Gene (June 2022).

4390: 303:

in the early 1990s, which provided conclusive evidence that the K–Pg boundary clay represented debris from an

16743: 16647: 15504: 15492: 14446: 14007: 13964: 13923: 12758: 11602:

Pope, K. O.; Ocampo, A. C.; Kinsland, G. L.; Smith, R. (1996). "Surface expression of the Chicxulub crater".

11345:"Ejecta layer at the Cretaceous-Tertiary boundary, Bass River, New Jersey (Ocean Drilling Program Leg 174AX)" 10132:"Albian-Paleocene flora of the north pacific: Systematic composition, palaeofloristics and phytostratigraphy" 9875: 7629: 6847: 5592: 5314: 3546: 3344:"Rapid ocean acidification and protracted Earth system recovery followed the end-Cretaceous Chicxulub impact" 2217: 2109: 569: 524: 429: 14359:"Recurring volcanic winters during the latest Cretaceous: Sulfur and fluorine budgets of Deccan Traps lavas" 10374:"Early evolution of modern birds structured by global forest collapse at the end-Cretaceous mass extinction" 16478: 15569: 15524: 14582: 12470: 9512:

Springer, Mark S.; Foley, Nicole M.; Brady, Peggy L.; Gatesy, John; Murphy, William J. (29 November 2019).

6120:"Belemnite extinction and the origin of modern cephalopods 35 m.y. prior to the Cretaceous−Paleogene event" 1740:, the largest known mass extinction in Earth's history, with up to 96% of all species suffering extinction. 536: 441: 14625: 10424:"Online guide to the continental Cretaceous–Tertiary boundary in the Raton basin, Colorado and New Mexico" 6568:"Global impact and selectivity of the Cretaceous-Paleogene mass extinction among sharks, skates, and rays" 5587: 3587:

Chiarenza, Alfio Alessandro; Farnsworth, Alexander; Mannion, Philip D.; Lunt, Daniel J.; Valdes, Paul J.;

2910: 2850: 2321:

definitively known to be associated with an impact, and other large extraterrestrial impacts, such as the

1071:, produced by either cicada nymphs or beetle larvae, over the course of the K-Pg transition show that the 16758: 16728: 16692: 16563: 14681: 13006: 12009: 11648: 11048:. Vol. Special Publication 190. Boulder, Colorado: Geological Society of America. pp. 291–296. 10450: 8131:"Biotic and abiotic factors and the phylogenetic structure of extinction in the evolution of Tethysuchia" 7873:

Fischer, Valentin; Bardet, Nathalie; Benson, Roger B. J.; Arkhangelsky, Maxim S.; Friedman, Matt (2016).

7623:Čerňanský, Andrej; Daza, Juan; Tabuce, Rodolphe; Saxton, Elizabeth; Vidalenc, Dominique (December 2023). 7162:"Temporal changes within the latest Cretaceous and early Paleogene turtle faunas of northeastern Montana" 6375:

Wiest, Logan A.; Lukens, William E.; Peppe, Daniel J.; Driese, Steven G.; Tubbs, Jack (1 February 2018).

5213: 2310:

also increased and caused particularly devastating global warming because of the consequent increases in

1254: 768:

suggests that biotic recovery was more rapid in the Southern Hemisphere than in the Northern Hemisphere.

529: 434: 8023:

Aubier, Paul; Jouve, Stéphane; Schnyder, Johann; Cubo, Jorge (20 February 2023). Mannion, Philip (ed.).

4703:

Bown, P. (2005). "Selective calcareous nannoplankton survivorship at the Cretaceous–Tertiary boundary".

1633: 995:

bivalves from the Late Cretaceous of the Omani Mountains, United Arab Emirates. Scale bar is 10 mm.

966:

of marine invertebrates, survived the K–Pg extinction event and diversified during the early Paleocene.

737:

included these shell builders, became extinct or suffered heavy losses. For example, it is thought that

537: 442: 353:

A wide range of terrestrial species perished in the K–Pg extinction, the best-known being the non-avian

16211: 11555: 11344: 10023:

Wappler, Torsten; Currano, Ellen D.; Wilf, Peter; Rust, Jes; Labandeira, Conrad C. (22 December 2009).

9257: 3893: 3066: 2344: 1833: 1794:

suggests that the Cretaceous-Paleogene mass extinction happened during the Northern Hemisphere spring.

1208:

palatal teeth suggest that there were dietary changes among the various species across the K–Pg event.

15190: 15093: 13098:"Site of asteroid impact changed the history of life on Earth: The low probability of mass extinction" 10335:

Schultz, P.; d'Hondt, S. (1996). "Cretaceous–Tertiary (Chicxulub) impact angle and its consequences".

10228:"No phylogenetic evidence for angiosperm mass extinction at the Cretaceous–Palaeogene (K-Pg) boundary" 10082:

Herman, A. B.; Akhmetiev, M. A.; Kodrul, T. M.; Moiseeva, M. G.; Iakovleva, A. I. (24 February 2009).

8631:"The Hell Creek Formation and its contribution to the Cretaceous–Paleogene extinction: A short primer" 6376: 5034:"Sedimentology and extinction patterns across the Cretaceous-Tertiary boundary interval in east Texas" 4549:"Mosasaur predation on upper Cretaceous nautiloids and ammonites from the United States Pacific Coast" 3410:

Earth and Life: Global Biodiversity, Extinction Intervals and Biogeographic Perturbations Through Time

2277:

would have a reasonable chance of survival. In 2016, a scientific drilling project obtained deep rock-

1694:

Beyond extinction impacts, the event also caused more general changes of flora such as giving rise to

973:

genera exhibited significant diminution after the K–Pg boundary. Entire groups of bivalves, including

16553: 15906: 15772: 15589: 13713:"Impact winter and the Cretaceous/Tertiary extinctions: Results of a Chicxulub asteroid impact model" 13261:"On transient climate change at the Cretaceous−Paleogene boundary due to atmospheric soot injections" 12861: 11091:"A Short Duration of the Cretaceous-Tertiary Boundary Event: Evidence from Extraterrestrial Helium-3" 10641:"The terminal Paleozoic fungal event: evidence of terrestrial ecosystem destabilization and collapse" 8075: 1960: 1276:, a diverse group of mainly herbivorous lizards known predominantly from the Northern Hemisphere The 535: 534: 440: 439: 14274:"Deccan volcanism at the Cretaceous-Tertiary boundary: past climatic crises as a key to the future?" 13817:"Hydrocode simulation of the Chicxulub impact event and the production of climatically active gases" 12245: 9214:"Phylogenomics and Morphology of Extinct Paleognaths Reveal the Origin and Evolution of the Ratites" 8213: 1956: 632:

reaching the ground. This plant extinction caused a major reshuffling of the dominant plant groups.

531: 436: 16585: 16577: 16473: 16425: 16181: 15858: 15712: 14577: 12590:"A possible tsunami deposit at the Cretaceous-Tertiary boundary in Pernambuco, northeastern Brazil" 8928: 2562: 2049: 1031:

class Cephalopoda became extinct at the K–Pg boundary. These included the ecologically significant

530: 528: 509: 435: 433: 331:

and produced long-lasting effects on the climate, detailing the mechanisms of the mass extinction.

15043:"State shift in Deccan volcanism at the Cretaceous-Paleogene boundary, possibly induced by impact" 7665:"Calcium Isotopic Evidence for Vulnerable Marine Ecosystem Structure Prior to the K/Pg Extinction" 6930:

Estes, R. (1964). "Fossil vertebrates from the late Cretaceous Lance formation, eastern Wyoming".

4500:"Shifts in food webs and niche stability shaped survivorship and extinction at the end-Cretaceous" 2208:

The re-entry of ejecta into Earth's atmosphere included a brief (hours-long) but intense pulse of

538: 533: 443: 438: 16523: 15736: 15488: 15276:"Calcareous Nannofossil Succession across the Cretaceous/Tertiary Boundary in East-Central Texas" 14951: 14717: 14484: 13768: 12276: 12089: 11902: 11757: 11271: 9071: 8029: 7825: 7216: 6676: 6632: 5779: 5635: 5539: 5309: 4832:

Schueth, Jonathan D.; Bralower, Timothy J.; Jiang, Shijun; Patzkowsky, Mark E. (September 2015).

2482: 2433: 2265: 1804: 1421: 1401: 1308:

had disappeared from fossil record tens of millions of years prior to the K-Pg extinction event.

14765: 14483:

Berggren, W.A; Aubry, M.-P; van Fossen, M; Kent, D.V; Norris, R.D; Quillévéré, F (1 June 2000).

14273: 14225: 14160:

Courtillot, V.; Féraud, G.; Maluski, H.; Vandamme, D.; Moreau, M. G.; Besse, J. (30 June 1988).

14054: 13816: 13712: 13664: 13616: 12749: 12514: 11809:

Paper No. 113–16, presented 23 October 2017 at the GSA Annual Meeting, Seattle, Washington, USA.

11806: 11792:

Paper No. 113–15, presented 23 October 2017 at the GSA Annual Meeting, Seattle, Washington, USA.

11789: 11090: 8684: 8590: 8353: 7762:

Chatterjee, S.; Small, B. J. (1989). "New plesiosaurs from the Upper Cretaceous of Antarctica".

5102:"The Cretaceous-Tertiary boundary transition in the Antarctic Ocean and its global implications" 5101: 5033: 2306:

rain through the production of nitrogen oxides and their subsequent reaction with water vapour.

1729:

are almost exclusive microfossils for a short span during and after the iridium boundary. These

460: 84: 16390: 16342: 15000:"Stable climate in India during Deccan volcanism suggests limited influence on K–Pg extinction" 13446: 13383:"Global climate change driven by soot at the K-Pg boundary as the cause of the mass extinction" 12893:"Energy, volatile production, and climatic effects of the Chicxulub Cretaceous/Tertiary impact" 12787:

Smit, Jan (1999). "The global stratigraphy of the Cretaceous-Tertiary boundary impact ejecta".

12240: 10287: 8557: 8409: 8357: 8312:"The rise of birds and mammals: Are microevolutionary processes sufficient for macroevolution?" 8135: 7121:"100 million years of land vertebrate evolution: The Cretaceous-early Tertiary transition" 5886: 5634:

Hyžný, Matúš; Perrier, Vincent; Robin, Ninon; Martin, Jeremy E.; Sarr, Raphaël (January 2016).

5266: 5032:

Hansen, T.; Farrand, R.B.; Montgomery, H.A.; Billman, H.G.; Blechschmidt, G. (September 1987).

4838: 4749: 4250: 4171: 4006:"The fossil record of North American Mammals: evidence for a Palaeocene evolutionary radiation" 3909:"Ecomorphological selectivity among marine teleost fishes during the end-Cretaceous extinction" 3419: 2224:

suggested that, based on the amount of soot in the global debris layer, the entire terrestrial

2124: 1730: 1657: 1417: 947:) areas of the ocean were less impacted by the K–Pg boundary. Colonial coral species rely upon 14867: 13498:"Rapid short-term cooling following the Chicxulub impact at the Cretaceous–Paleogene boundary" 12665: 11446:"Shocked quartz in the Cretaceous-Tertiary boundary clays: Evidence for a global distribution" 7196: 6377:"Terrestrial evidence for the Lilliput effect across the Cretaceous-Paleogene (K-Pg) boundary" 3204:"Rapid short-term cooling following the Chicxulub impact at the Cretaceous-Paleogene boundary" 1656:

Due to the wholesale destruction of plants at the K–Pg boundary, there was a proliferation of

617:. Nevertheless, high latitudes appear to have been less strongly affected than low latitudes. 16753: 16513: 16468: 16347: 16236: 16226: 15832: 15385: 15326: 15144:

Li, Liangquan; Keller, Gerta (1998). "Abrupt deep-sea warming at the end of the Cretaceous".

14025: 14001: 13984: 13958: 13917: 12277:"NASA's WISE raises doubt about asteroid family believed responsible for dinosaur extinction" 11244: 9518: 9305: 8290: 7879: 7733: 7570: 5732:

Raup, D. M.; Jablonski, D. (1993). "Geography of end-Cretaceous marine bivalve extinctions".

5006: 2322: 850:

to the Upper Paleocene, a significant turnover in species but not a catastrophic extinction.

14718:"Late Cretaceous to early Paleocene climate and sea-level fluctuations: the Tunisian record" 14694: 14335: 14243: 13786: 13730: 13682: 13634: 13259:

Bardeen, Charles G.; Garcia, Rolando R.; Toon, Owen B.; Conley, Andrew J. (21 August 2017).

12236: 11160: 11043: 8549: 8253:

Slack, K, E; Jones, C M; Ando, T; Harrison, G L; Fordyce, R E; Arnason, U; Penny, D (2006).

4163: 3971:

Jablonski, D.; Chaloner, W. G. (1994). "Extinctions in the fossil record (and discussion)".

3407: 2709: 2151:

Artistic impression of the asteroid slamming into tropical, shallow seas of the sulfur-rich

208:

weighing more than 25 kilograms (55 pounds) also became extinct, with the exception of some

16616: 16385: 16375: 16332: 15582: 15417: 15335: 15155: 15110: 15056: 15013: 14965: 14906: 14817: 14731: 14690: 14639: 14542: 14498: 14372: 14331: 14287: 14239: 14175: 14111: 13830: 13782: 13726: 13678: 13630: 13511: 13441: 13210: 13169: 13109: 12906: 12835: 12798: 12715: 12638: 12601: 12562: 12479: 12412: 12364: 12232: 12203: 12139: 11962: 11914: 11859: 11711: 11613: 11512: 11459: 11402: 11309: 11156: 11107: 10963: 10876: 10863:

During, Melanie A. D.; Smit, Jan; Voeten, Dennis F. A. E.; et al. (23 February 2022).

10819: 10761: 10713: 10654: 10582: 10493: 10346: 9930: 9854: 9763: 9640: 9373: 9269: 9160: 9021: 8961: 8882: 8873: 8830: 8785: 8720: 8644: 8418: 8366: 8087: 8038: 7888: 7839: 7771: 7579: 7528: 7463: 7326: 6756: 6641: 6581: 6532: 6470: 6390: 6333: 6276: 6133: 6092: 6052: 5838: 5788: 5743: 5683: 5447: 5358: 4971: 4889: 4786:"Geographic controls on nannoplankton extinction across the Cretaceous/Palaeogene boundary" 4714: 4677: 4615: 4565: 4471: 4431: 4378: 4326: 4066: 3922: 3835: 3748: 3682: 3606: 3525: 3449: 3415: 3357: 3277: 3217: 3150: 2992: 2922: 2864: 2805: 2478: 2449: 2261: 2017: 1841: 1759: 1747: 1481: 1409: 1257:. Outside of New Zealand, one rhynchocephalian is known to have crossed the K-Pg boundary, 900: 12943: 9514:"Evolutionary Models for the Diversification of Placental Mammals Across the KPg Boundary" 7164:. In Wilson, Gregory P.; Clemens, William A.; Horner, John R.; Hartman, Joseph H. (eds.). 6567: 2493:

environments, since continental runoff now had longer distances to travel before reaching

2152: 1997: 1983:

and other minerals were also identified in the K–Pg boundary. The identification of giant

300: 200:

approximately 66 million years ago. The event caused the extinction of all non-avian

8: 16682: 16445: 16327: 16322: 16312: 16231: 16174: 14893:"The eruptive tempo of Deccan volcanism in relation to the Cretaceous-Paleogene boundary" 14578:"No Evidence for a Large Atmospheric CO 2 Spike Across the Cretaceous-Paleogene Boundary" 14533: 13048:

Morgan, Joanna V.; Bralower, Timothy J.; Brugger, Julia; Wünnemann, Kai (12 April 2022).

12399:"Meteorite impact and the mass extinction of species at the Cretaceous/Tertiary boundary" 10702:"Palaeobotanical evidence for a June 'impact winter' at the Cretaceous/Tertiary boundary" 9624: 8635: 8513: 7936: 7830: 7211: 6681: 5640: 5038: 2565: – One of the five most severe extinction events in the history of the Earth's biota 2156: 2005: 1916: 1880: 1787: 1492: 1477: 892: 765: 472: 328: 260: 15574: 15559: 15421: 15339: 15159: 15114: 15060: 15017: 14969: 14910: 14821: 14735: 14643: 14546: 14502: 14401: 14376: 14358: 14291: 14179: 14115: 13834: 13711:

Pope, Kevin O.; Baines, Kevin H.; Ocampo, Adriana C.; Ivanov, Boris A. (December 1994).

13515: 13214: 13173: 13113: 12910: 12839: 12802: 12719: 12642: 12605: 12566: 12483: 12416: 12368: 12207: 12143: 11966: 11918: 11863: 11715: 11617: 11516: 11463: 11406: 11390: 11313: 11111: 10967: 10880: 10823: 10765: 10717: 10658: 10586: 10539: 10497: 10350: 10260: 10227: 9934: 9858: 9767: 9644: 9377: 9273: 9164: 9025: 8965: 8886: 8834: 8789: 8724: 8648: 8422: 8370: 8091: 8042: 7979:

Jouve, S.; Bardet, N.; Jalil, N.-E.; Suberbiola, X. P.; Bouya, B.; Amaghzaz, M. (2008).

7892: 7843: 7775: 7624: 7583: 7532: 7467: 7330: 6760: 6645: 6585: 6536: 6474: 6394: 6337: 6280: 6235: 6198: 6137: 6096: 6056: 5842: 5792: 5747: 5687: 5451: 5362: 4975: 4893: 4718: 4681: 4619: 4569: 4475: 4435: 4382: 4330: 4070: 3926: 3839: 3822:"First evidence for a massive extinction event affecting bees close to the K-T boundary" 3752: 3686: 3610: 3529: 3361: 3281: 3221: 3154: 3093: 2996: 2976:"The Chicxulub Asteroid Impact and Mass Extinction at the Cretaceous-Paleogene Boundary" 2926: 2868: 2809: 1671:

in the geologic record; this same pattern of fern recolonization was observed after the

16768: 15614: 15544: 15440: 15405: 15356: 15321: 15295: 15171: 15126: 14199: 14135: 13665:"Bolide impacts, acid rain, and biospheric traumas at the Cretaceous-Tertiary boundary" 13585: 13534: 13497: 13417: 13387: 13382: 13358: 13321: 13297: 13260: 13234: 13130: 13097: 12589: 12495: 12258: 12254: 12193: 12163: 12027: 11883: 11734: 11697: 11666: 11536: 11483: 11426: 11325: 11280: 11007: 10989: 10897: 10864: 10840: 10807: 10782: 10749: 10729: 10614: 10516: 10479: 10405: 10317: 10201: 10179: 10059: 10024: 9954: 9896: 9722: 9687: 9550: 9513: 9489: 9462: 9389: 9363: 9293: 9194: 9125: 9098: 9053: 8985: 8871: 8854: 8801: 8677: 8480: 8453: 8434: 8382: 8194: 8111: 8005: 7961: 7911: 7874: 7855: 7787: 7737: 7600: 7565: 7492: 7451: 7427: 7394: 7350: 7294: 7264: 7259: 7183: 7142: 7096: 7074: 7069: 7050: 7008: 6971: 6798: 6772: 6657: 6605: 6548: 6523: 6357: 5862: 5804: 5699: 5515: 5482: 5463: 5082: 4987: 4905: 4766: 4641: 4581: 4524: 4499: 4394: 4342: 4267: 4139: 4112: 4090: 4010: 3945: 3908: 3858: 3821: 3771: 3734: 3705: 3668: 3637: 3592: 3559: 3485: 3380: 3343: 3312: 3240: 3203: 3174: 3016: 2975: 2938: 2880: 2821: 2311: 2282: 2147: 2020:, a group of rocks spanning four states in North America renowned for many significant 1862: 1736:

The proliferation of fungi has occurred after several extinction events, including the

1624: 1615:

interpreted as diversifying immediately after the K–Pg boundary, including Chiroptera (

1442: 1359: 1273: 1237:

which were a globally distributed and diverse group of lepidosaurians during the early

1225:

diminished. European turtles likewise recovered rapidly following the mass extinction.

1048: 1012: 757: 698: 668: 394: 288: 268: 137:

than the upper and lower layers. Picture taken at the San Diego Natural History Museum;

14743: 14702: 14673: 14554: 14510: 11985: 11948: 11926: 11758:"National Natural Landmarks – National Natural Landmarks (U.S. National Park Service)" 11500: 11185: 10196: 9839: 9747:"Cope's rule and the dynamics of body mass evolution in North American fossil mammals" 9746: 9663: 9626: 9004: 8311: 8211: 7980: 6299: 6262: 6080: 5966: 5929: 5370: 5347: 4548: 3511: 16652: 16538: 16528: 16281: 16241: 15748: 15477: 15467: 15445: 15361: 15254: 15212: 15175: 15146: 15074: 15047: 15004: 14932: 14924: 14897: 14871: 14860: 14833: 14808: 14781: 14599: 14558: 14450: 14406: 14388: 14299: 14251: 14191: 14127: 14072: 14033: 14021: 13876: 13846: 13742: 13738: 13690: 13642: 13539: 13471: 13463: 13422: 13404: 13363: 13345: 13302: 13284: 13238: 13226: 13201: 13196: 13160: 13135: 13071: 13049: 13023: 12975: 12924: 12731: 12706: 12671: 12629: 12613: 12551: 12525: 12440: 12435: 12398: 12348: 12155: 12031: 11990: 11946: 11875: 11850: 11739: 11670: 11629: 11604: 11577: 11560: 11528: 11503: 11475: 11450: 11418: 11393: 11366: 11349: 11215: 11207: 11190: 11123: 11098: 11059: 11049: 10993: 10981: 10925: 10902: 10845: 10787: 10682: 10677: 10640: 10618: 10606: 10598: 10573: 10568: 10521: 10397: 10337: 10309: 10292: 10265: 10247: 10205: 10153: 10131: 10105: 10083: 10064: 10046: 10003: 9977: 9946: 9921: 9900: 9888: 9880: 9845: 9779: 9754: 9727: 9709: 9668: 9604: 9592: 9555: 9537: 9494: 9412: 9393: 9285: 9237: 9198: 9186: 9151: 9130: 9045: 9002: 8977: 8952: 8846: 8821: 8805: 8688: 8569: 8550: 8524: 8485: 8336: 8278: 8152: 8115: 8103: 8056: 7965: 7953: 7916: 7859: 7791: 7696: 7688: 7605: 7546: 7497: 7479: 7432: 7414: 7373: 7342: 7299: 7281: 7233: 7169: 7101: 7013: 6995: 6910: 6872: 6864: 6816: 6661: 6609: 6597: 6572: 6552: 6501: 6436: 6406: 6349: 6324: 6304: 6240: 6222: 6149: 6124: 6083: 6043: 6012: 5971: 5953: 5903: 5854: 5829: 5808: 5759: 5734: 5703: 5609: 5520: 5502: 5416: 5397: 5283: 5235: 5231: 5192: 5161: 5117: 5051: 5012: 4991: 4942: 4909: 4855: 4807: 4790: 4705: 4668: 4645: 4585: 4529: 4462: 4422: 4369: 4346: 4185: 4175: 4164: 4144: 4082: 4057: 4029: 3950: 3863: 3800: 3776: 3710: 3642: 3624: 3563: 3551: 3516: 3423: 3408: 3385: 3268: 3245: 3166: 3141: 3131: 3008: 2983: 2942: 2884: 2825: 2766: 2741: 2685: 2515: 2469: 2299: 2228:

might have burned, implying a global soot-cloud blocking out the sun and creating an

2131: 1695: 1170: 1042:

Approximately 35% of echinoderm genera became extinct at the K–Pg boundary, although

869: 777: 710: 628:

declined or became extinct as atmospheric particles blocked sunlight and reduced the

267:, it is now generally thought that the K–Pg extinction was caused by the impact of a 117: 12499: 12262: 12180: 11887: 11487: 11430: 10409: 10321: 9958: 9347: 8989: 8858: 8438: 8386: 8198: 8009: 7741: 7054: 6842: 6776: 6361: 4770: 4398: 4271: 4094: 3178: 2399:

would since have been obscured by the northward tectonic drift of Africa and India.

1508: 123:

Complex Cretaceous–Paleogene clay layer (gray) in the Geulhemmergroeve tunnels near

16657: 16405: 16380: 16337: 16307: 16256: 16251: 15681: 15639: 15628: 15435: 15425: 15351: 15343: 15287: 15246: 15239:"The Cretaceous/Tertiary boundary impact hypothesis and the paleontological record" 15204: 15163: 15130: 15118: 15064: 15021: 14973: 14914: 14825: 14777: 14739: 14698: 14647: 14591: 14550: 14506: 14442: 14396: 14380: 14363: 14339: 14295: 14247: 14203: 14183: 14166: 14139: 14119: 14102: 14068: 13838: 13790: 13734: 13686: 13638: 13562: 13529: 13519: 13455: 13442:"Chicxulub and Climate: Radiative Perturbations of Impact-Produced S-Bearing Gases" 13412: 13396: 13353: 13335: 13292: 13274: 13218: 13177: 13125: 13117: 13063: 13015: 12965: 12957: 12914: 12843: 12806: 12723: 12646: 12609: 12570: 12487: 12430: 12420: 12372: 12250: 12167: 12147: 12130: 12103: 12023: 11980: 11970: 11922: 11867: 11729: 11719: 11662: 11621: 11569: 11540: 11520: 11467: 11410: 11358: 11329: 11317: 11300: 11199: 11164: 11115: 11039: 10971: 10954: 10892: 10884: 10835: 10827: 10777: 10769: 10733: 10721: 10672: 10662: 10590: 10569:"Extinction at the end-Cretaceous and the origin of modern Neotropical rainforests" 10511: 10501: 10387: 10354: 10301: 10255: 10239: 10191: 10145: 10097: 10054: 10038: 9938: 9870: 9862: 9771: 9717: 9701: 9658: 9648: 9600: 9584: 9545: 9527: 9484: 9476: 9461:

Pires, Mathias M.; Rankin, Brian D.; Silvestro, Daniele; Quental, Tiago B. (2018).

9381: 9297: 9277: 9260: 9227: 9176: 9168: 9120: 9112: 9057: 9037: 9029: 9012: 9003:

Clarke, J.A.; Tambussi, C.P.; Noriega, J.I.; Erickson, G.M.; Ketcham, R.A. (2005).

8969: 8838: 8818: 8793: 8772: 8755: 8728: 8652: 8604: 8561: 8475: 8465: 8426: 8374: 8328: 8268: 8186: 8176: 8144: 8095: 8046: 7997: 7945: 7906: 7896: 7847: 7779: 7729: 7678: 7638: 7595: 7587: 7566:"Evolution and dispersal of snakes across the Cretaceous-Paleogene mass extinction" 7536: 7487: 7471: 7422: 7406: 7354: 7334: 7289: 7273: 7225: 7134: 7091: 7083: 7042: 7003: 6985: 6902: 6856: 6806: 6764: 6698: 6690: 6649: 6589: 6540: 6478: 6398: 6341: 6294: 6284: 6230: 6212: 6141: 6100: 6060: 6039: 6004: 5961: 5943: 5895: 5866: 5846: 5796: 5751: 5691: 5649: 5601: 5559: 5555: 5551: 5510: 5494: 5455: 5393: 5366: 5323: 5275: 5227: 5153: 5113: 5047: 4979: 4934: 4897: 4847: 4799: 4758: 4722: 4685: 4631: 4623: 4573: 4519: 4511: 4479: 4439: 4386: 4334: 4259: 4218: 4134: 4126: 4074: 4019: 3980: 3940: 3930: 3853: 3843: 3766: 3756: 3700: 3690: 3632: 3614: 3541: 3533: 3375: 3365: 3285: 3235: 3225: 3158: 3020: 3000: 2934: 2930: 2872: 2813: 2477:

and increasing global temperatures. Marine regression also resulted in the loss of

2372: 2352: 2318: 2160: 2097: 2033: 2025: 1993: 1989: 1932: 1866: 1837: 1578: 1371: 1123:(skates and rays) lost nearly all the identifiable species, while more than 90% of 835: 761: 726: 563: 292: 253: 182: 31: 12810: 11119: 9385: 8973: 8657: 8630: 8099: 7851: 7783: 7541: 7516: 6843:"Explosive diversification of marine fishes at the Cretaceous–Palaeogene boundary" 6694: 5850: 5653: 5588:"Selective extinction at the end-Cretaceous and appearance of the modern Decapoda" 4983: 4901: 4418: 3162: 1480:. Evidence of this existence is based on the discovery of dinosaur remains in the 127:, The Netherlands (finger is just below the actual Cretaceous–Paleogene boundary); 16365: 16302: 15520: 15461: 14977: 14651: 12847: 12626: 11524: 11471: 11414: 10378: 9775: 9467: 9218: 9103: 8842: 8732: 8608: 8470: 7669: 7395:"The youngest South American rhynchocephalian, a survivor of the K/Pg extinction" 7120: 6901:. Special Paper. Vol. 247. Geological Society of America. pp. 549–562. 6797:

Friedman, Matt; V. Andrews, James; Saad, Hadeel; El-Sayed, Sanaa (16 June 2023).

6737: 6674: 6482: 6402: 6217: 5327: 4078: 3848: 3098: 2876: 2462: 2302:. The heating of the atmosphere during the impact itself may have also generated 1984: 1944: 1524: 1504: 1363: 1318: 1234: 1072: 1060: 899:

There is significant variation in the fossil record as to the extinction rate of

343: 304: 233: 14098:"Rapid eruption of the Deccan flood basalts at the Cretaceous/Tertiary boundary" 11871: 11601: 11245:"Darkness caused by dino-killing asteroid snuffed out life on Earth in 9 months" 9099:"Diversification of Neoaves: integration of molecular sequence data and fossils" 8759: 7978: 7934:

Brochu, C. A. (2004). "Calibration age and quartet divergence date estimation".

7716:"Consequences of the Cretaceous/Paleogene Mass Extinction for Marine Ecosystems" 6321: 6260: 5308:

Schulte, Peter; Speijer, Robert; Mai, Hartmut; Kontny, Agnes (1 February 2006).

2679: 55: 16518: 16493: 15623: 15529: 15457: 15406:"A seismically induced onshore surge deposit at the KPg boundary, North Dakota" 14343: 13794: 13503: