2140:
1028:
2429:
1316:
2331:
1239:
113:
2351:
1259:
2486:
1373:
2951:
1849:
143:
2868:
1764:
2678:
1574:
659:
2658:
1554:
2799:
2714:
1695:
1610:
2232:
1116:
3013:
2888:
1911:
1784:
3067:
1965:
1084:
3046:
1944:
729:
2462:
1349:
2575:
1462:
3140:
3089:
2040:
1987:
2160:
1048:
2746:
1642:
2971:
2280:
1869:
1164:
2100:(corresponding to Nephrozoa without Ambulacraria, or to Chordata + Protostomia). The phylogenetic tree shown below depicts the latter proposal. Also, the validity of Deuterostomia (without Protostomia emerging from it) is under discussion. The cladogram indicates approximately when some clades radiated into newer clades, in millions of years ago (Mya). While the below tree depicts
2779:
1675:
981:
by Baguña and
Riutort (2004). The acoelomorph taxa had previously been considered flatworms with secondarily lost characteristics, but the new relationship suggested that the simple acoelomate worm form was the original bilaterian body plan and that the coelom, the digestive tract, excretory organs,
3930:
Hagadorn, J. W.; Xiao, S.; Donoghue, P. C. J.; Bengtson, S.; Gostling, N. J.; Pawlowska, M.; Raff, E. C.; Raff, R. A.; Turner, F. R.; Chongyu, Y.; Zhou, C.; Yuan, X.; McFeely, M. B.; Stampanoni, M.; Nealson, K. H. (13 October 2006). "Cellular and
Subcellular Structure of Neoproterozoic Animal
814:. Alternatively, it may have resembled the planula larvae of some cnidaria, which have some bilateral symmetry. However, there is evidence that it was segmented, as the mechanism for creating segments is shared between vertebrates (deuterostomes) and arthropods (protostomes).
4844:
Philippe, Hervé; Poustka, Albert J.; Chiodin, Marta; Hoff, Katharina J.; Dessimoz, Christophe; Tomiczek, Bartlomiej; et al. (2019). "Mitigating anticipated effects of systematic errors supports sister-group relationship between
Xenacoelomorpha and Ambulacraria".
662:
Idealised wormlike nephrozoan body plan. With a cylindrical body and a direction of movement the animal has head and tail ends. Sense organs and mouth form the basis of the head. Opposed circular and longitudinal muscles enable
671:
Some of the earliest bilaterians were wormlike, and a bilaterian body can be conceptualized as a cylinder with a gut running between two openings, the mouth and the anus. Around the gut it has an internal body cavity, a
2112:
according to analyses by
Philippe et al., the authors nonetheless caution that "the support values are very low, meaning there is no solid evidence to refute the traditional protostome and deuterostome dichotomy".
4342:
711:
and have an apical organ containing sensory cells. However, there are exceptions to each of these characteristics; for example, adult echinoderms are radially symmetric (unlike their larvae), and certain
3982:
Pecoits, E.; Konhauser, K. O.; Aubet, N. R.; Heaman, L. M.; Veroslavsky, G.; Stern, R. A.; Gingras, M. K. (June 29, 2012). "Bilaterian burrows and grazing behavior at >585 million years ago".
703:. Most bilaterians (nephrozoans) have a gut that extends through the body from mouth to anus, while xenacoelomorphs have a bag gut with one opening. Many bilaterian phyla have primary
768:
4117:
Halanych, K.; Bacheller, J.; Aguinaldo, A.; Liva, S.; Hillis, D.; Lake, J. (17 March 1995). "Evidence from 18S ribosomal DNA that the lophophorates are protostome animals".
868:
of
Uruguay, and were believed to be at least 585 million years old. However, more recent evidence shows these fossils are actually late Paleozoic instead of Ediacaran.
795:
755:". The nature of the first bilaterian is a matter of debate. One side suggests that acoelomates gave rise to the other groups (planuloid–aceloid hypothesis by
680:
have a head (anterior) end and a tail (posterior) end as well as a back (dorsal) and a belly (ventral); therefore they also have a left side and a right side.
865:
4254:
4170:"Bilaterian phylogeny: a broad sampling of 13 nuclear genes provides a new Lophotrochozoa phylogeny and supports a paraphyletic basal Acoelomorpha"
695:
that constrict the body, making it longer, and an opposing set of longitudinal muscles, that shorten the body; these enable soft-bodied animals with a
3447:
6136:
4799:
6141:
4556:
Edgecombe, Gregory D.; Giribet, Gonzalo; Dunn, Casey W.; Hejnol, Andreas; Kristensen, Reinhardt M.; Neves, Ricardo C.; et al. (June 2011).
5999:
7606:
3328:"Introduction to the Bilateria and the Phylum Xenacoelomorpha: Triploblasty and Bilateral Symmetry Provide New Avenues for Animal Radiation"
4911:
4728:
Kapli, Paschalia; Natsidis, Paschalis; Leite, Daniel J.; Fursman, Maximilian; Jeffrie, Nadia; Rahman, Imran A.; et al. (2021-03-19).
3504:"Ontogenetic scaling of hydrostatic skeletons: geometric, static stress and dynamic stress scaling of the earthworm lumbricus terrestris"
3198:
864:), but none of these have bilaterian affinities. Burrows believed to have been created by bilaterian life forms have been found in the
7662:
961:
was challenged when new morphological and molecular evidence found support for a sister relationship between the acoelomate taxa,
7593:
4501:
Cannon, Johanna Taylor; Vellutini, Bruno
Cossermelli; Smith, Julian; Ronquist, Fredrik; Jondelius, Ulf; Hejnol, Andreas (2016).
3361:
Cannon, Johanna Taylor; Vellutini, Bruno
Cossermelli; Smith, Julian; Ronquist, Fredrik; Jondelius, Ulf; Hejnol, Andreas (2016).
930:
develops. In particular, the first opening of the embryo becomes the mouth in protostomes, and the anus in deuterostomes. Many
3777:
3430:
3342:
7598:
2139:
1027:
7657:
4947:
6237:
500:) surface. Nearly all bilaterians maintain a bilaterally symmetrical body as adults; the most notable exception is the
456:
384:
6274:
4981:
7611:
6269:
4976:
877:
808:
One hypothesis is that the original bilaterian was a bottom dwelling worm with a single body opening, similar to
773:
3448:"Did internal transport, rather than directed locomotion, favor the evolution of bilateral symmetry in animals?"
3257:
4320:
4294:
786:) have lost body cavities secondarily (the Archicoelomata hypothesis and its variations such as the Gastrea by
4258:
122:
6353:
6343:
6326:
5060:
5050:
5033:
119:
3478:
778:), while the other poses that the first bilaterian was a coelomate organism and the main acoelomate phyla (
4795:"The Ediacaran emergence of bilaterians: congruence between the genetic and the geological fossil records"
4399:"Identification of chaetognaths as protostomes is supported by the analysis of their mitochondrial genome"
4034:
3763:
748:
120:
990:, and the sister relationship between Xenacoelomorpha and Nephrozoa confirmed in phylogenomic analyses.
691:
and a mouth. The body stretches back from the head, and many bilaterians have a combination of circular
123:
121:
3769:
116:
3503:
3327:
492:
axis) with a front (or "head") and a rear (or "tail") end, as well as a left–right–symmetrical belly (
142:
118:
4035:"Revisiting the supposed oldest bilaterian trace fossils from Uruguay: Late Paleozoic, not Ediacaran"
791:
485:
3671:
4679:"Phylogenetic position of Loricifera inferred from nearly complete 18S and 28S rRNA gene sequences"
2092:
A different hypothesis is that the
Ambulacraria are sister to Xenacoelomorpha together forming the
489:
117:
6358:
5065:
4940:
4332:
Helfenbein, Kevin G.; Fourcade, H. Matthew; Vanjani, Rohit G.; Boore, Jeffrey L. (20 July 2004).
800:
3238:
982:
and nerve cords developed in the
Nephrozoa. Subsequently the acoelomorphs were placed in phylum
683:
Having a front end means that this part of the body encounters stimuli, such as food, favouring
7624:
7507:
6230:
4908:
3666:
3614:(25 June 1999). "Early Animal Evolution: Emerging Views from Comparative Biology and Geology".
2529:
1416:
521:
7619:
6321:
5028:
4071:
Nielsen, Claus (2008). "Six major steps in animal evolution: are we derived sponge larvae?".
3420:
477:
3239:"Patterns of distribution in the Ediacaran biotas: facies versus biogeography and evolution"
7652:
7647:
7567:
7554:
4741:
4611:
4514:
4454:
4351:
4126:
3991:
3940:
3806:
3556:
3374:
2428:
2350:
2330:
1315:
1258:
1238:
696:
505:
8:
7545:
5843:
5627:
4793:
Peterson, Kevin J.; Cotton, James A.; Gehling, James G.; Pisani, Davide (27 April 2008).
1001:
are still controversial (dashed lines) and the tree has changed considerably since 2000.
4745:
4615:
4518:
4502:
4458:
4355:
4130:
3995:
3944:
3810:
3657:
Balavoine, G.; Adoutte, Andre (2003). "The segmented
Urbilateria: A testable scenario".
3560:
3378:
3362:
3299:
6786:
6338:
6316:
6304:
6279:
5853:
5045:
5023:
5011:
4986:
4933:
4888:
4821:
4794:
4770:
4729:
4705:
4678:
4635:
4577:
4538:
4475:
4442:
4150:
4096:
4015:
3964:
3912:
3884:
3844:"Comment on 'small bilaterian fossils from 40 to 55 million years before the Cambrian'"
3824:
3736:
3711:
3692:
3639:
3587:
3544:
3398:
3279:
3261:
2930:
1828:
947:
931:
469:
320:
137:
4653:
4557:
4374:
4333:
3882:
7208:
7128:
6478:
6348:
6311:
6299:
6289:
6223:
6187:
6113:
6094:
5804:
5387:
5055:
5018:
5006:
4996:
4892:
4880:
4872:
4867:
4826:
4775:
4757:
4710:
4639:
4627:
4542:
4530:
4480:
4420:
4379:
4316:
4300:
4290:
4232:
4191:
4142:
4088:
4084:
4007:
3956:
3916:
3904:
3900:
3865:
3773:
3741:
3684:
3631:
3592:
3574:
3525:
3470:
3426:
3402:
3390:
3338:
3265:
994:
205:
4920:
4581:
4154:
4019:
3968:
3696:
3543:
Evans, Scott D.; Hughes, Ian V.; Gehling, James G.; Droser, Mary L. (7 April 2020).
6263:
6159:
6105:
5859:
5305:
4970:
4862:
4854:
4816:
4808:
4765:
4749:
4730:"Lack of support for Deuterostomia prompts reinterpretation of the first Bilateria"
4700:
4690:
4619:
4569:
4522:
4470:
4462:
4410:
4369:
4359:
4284:
4222:
4181:
4134:
4100:
4080:
4046:
3999:
3948:
3896:
3855:
3828:
3814:
3731:
3723:
3676:
3643:
3623:
3582:
3564:
3515:
3462:
3382:
3253:
2260:
1144:
966:
760:
756:
733:
497:
415:
346:
256:
7559:
6482:
5791:
4397:
Papillon, Daniel; Perez, Yvan; Caubit, Xavier; Yannick Le, Parco (November 2004).
4338:
is highly reduced and reveals that chaetognaths are a sister group to protostomes"
3627:
7489:
7395:
7246:
7149:
7006:
6539:
6032:
5207:
4915:
4280:
4273:
4250:
4227:
4210:
4050:
3611:
3304:
3284:
3007:
2485:
2424:
2213:
2201:
2093:
1905:
1372:
1311:
1097:
983:
849:
may be the earliest known bilaterian, but may also represent an infilled bubble.
822:
The first evidence of bilateria in the fossil record comes from trace fossils in
639:
603:
282:
276:
236:
230:
4800:
Philosophical Transactions of the Royal Society of London B: Biological Sciences
4443:"Rotiferan Hox genes give new insights into the evolution of metazoan bodyplans"
737:, living 571–539 million years ago, is one of the oldest bilaterians identified.
7154:
6950:
6862:
6840:
6803:
6294:
6128:
6118:
6082:
6057:
5746:
5537:
5438:
5360:
5169:
5001:
4466:
4343:
Proceedings of the National Academy of Sciences of the United States of America
3026:
2993:
2398:
2227:
2097:
1924:
1891:
1111:
850:
845:
631:
599:
4858:
4695:
4573:
4558:"Higher-level metazoan relationships: recent progress and remaining questions"
4304:
4116:
3795:"The Late Precambrian fossil Kimberella is a mollusc-like bilaterian organism"
2867:
1763:
7641:
7299:
7203:
6702:
6164:
5963:
5955:
5785:
5706:
5646:
5557:
5531:
5260:
4876:
4761:
3759:
3578:
2950:
2727:
2677:
2570:
2554:
2326:
2188:
1848:
1623:
1573:
1457:
1441:
1234:
1207:
1075:
987:
954:
787:
717:
684:
615:
575:
517:
513:
265:
221:
70:
4921:
University of California Museum of Paleontology — Systematics of the Metazoa
4415:
4398:
4364:
4186:
4169:
4138:
4003:
3952:
3860:
3843:
3569:
3520:
7405:
7400:
7288:
7144:
7030:
6916:
6819:
6798:
6668:
6619:
6575:
6556:
6197:
6024:
6004:
5944:
5848:
5821:
5768:
5726:
5693:
5468:
5246:
5185:
4925:
4884:
4830:
4812:
4779:
4753:
4714:
4631:
4534:
4484:
4424:
4383:
4236:
4195:
4092:
4011:
3960:
3908:
3869:
3745:
3727:
3688:
3680:
3635:
3596:
3474:
3394:
2966:
2848:
2673:
2367:
2346:
2311:
2245:
2105:
1864:
1744:
1569:
1275:
1254:
1219:
1129:
970:
943:
895:
887:
810:
764:
752:
627:
567:
473:
401:
328:
288:
241:
4146:
3545:"Discovery of the oldest bilaterian from the Ediacaran of South Australia"
3529:
2657:
1553:
7580:
7539:
7530:
7366:
7337:
7323:
7313:
6898:
6714:
6627:
6409:
6088:
6014:
5866:
5830:
5810:
5758:
5732:
5622:
5570:
5543:
5525:
5498:
5265:
5134:
5123:
4596:
3710:
Baguñà, Jaume; Martinez, Pere; Paps, Jordi; Riutort, Marta (April 2008).
3217:
The earliest Bilateria may have had only a single opening, and no coelom.
2883:
2798:
2741:
2713:
2606:
2457:
2121:
2109:
1779:
1694:
1637:
1609:
1502:
1009:
978:
958:
903:
783:
742:
700:
688:
664:
555:
297:
187:
45:
4623:
4526:
3765:
How the Snake Lost its Legs. Curious Tales from the Frontier of Evo-Devo
3386:
2231:
1115:
7463:
7448:
7443:
7424:
7419:
7347:
7294:
7264:
7256:
7198:
7072:
7064:
7047:
6827:
6739:
6692:
6632:
6594:
6568:
6414:
6399:
6169:
5993:
5984:
5969:
5837:
5774:
5633:
5594:
5589:
5475:
5392:
5287:
5199:
3466:
3134:
3083:
3012:
2887:
2863:
2794:
2774:
2709:
2481:
2442:
2035:
2031:
1981:
1910:
1783:
1759:
1690:
1670:
1605:
1368:
1329:
1079:
926:, and so forth. There are several differences, most notably in how the
907:
891:
883:
882:
The Bilateria has traditionally been divided into two main lineages or
832:
658:
635:
619:
579:
563:
501:
260:
225:
90:
55:
7585:
6215:
3716:
Philosophical Transactions of the Royal Society B: Biological Sciences
1083:
946:) have proven difficult to classify; recent studies place them in the
7429:
7376:
7371:
7342:
7331:
7280:
7275:
7227:
7139:
6926:
6921:
6883:
6732:
6724:
6653:
6605:
6494:
6489:
6068:
6009:
5717:
5682:
5640:
5617:
5599:
5486:
5422:
5297:
5174:
5117:
5104:
4956:
3883:
Bengtson, S.; Donoghue, P. C. J.; Cunningham, J. A.; Yin, C. (2012).
2759:
2638:
2618:
1655:
1534:
1514:
1195:
974:
935:
911:
859:
838:
823:
713:
677:
647:
547:
481:
302:
249:
174:
154:
95:
39:
28:
7501:
4677:
Yamasaki, Hiroshi; Fujimoto, Shinta; Miyazaki, Katsumi (June 2015).
3045:
1943:
7524:
7453:
7437:
7360:
7352:
7307:
7270:
7251:
7240:
7222:
7216:
7077:
7018:
6994:
6891:
6772:
6661:
6545:
6436:
6427:
6333:
6075:
6037:
5938:
5915:
5462:
5457:
5449:
5379:
5254:
5129:
5112:
5090:
5040:
4597:"Hallucigenia's onychophoran-like claws and the case for Tactopoda"
3061:
3041:
2945:
2919:
2653:
2477:
2410:
2155:
2135:
2101:
1959:
1939:
1843:
1816:
1549:
1364:
1344:
1297:
1043:
1023:
939:
923:
899:
779:
728:
623:
595:
591:
587:
583:
571:
551:
543:
535:
531:
516:
is also a characteristic feature among most bilaterians, where the
307:
271:
85:
80:
65:
60:
50:
32:
4257:(online biology textbook). Kimball's Biology Pages. Archived from
3819:
3794:
3066:
2461:
1964:
1348:
934:
now recognize at least two more superphyla among the protostomes,
7413:
7389:
7381:
7318:
7232:
7052:
7039:
6972:
6963:
6908:
6833:
6191:
5926:
5763:
5609:
5516:
5505:
5369:
5275:
5231:
5139:
2574:
1461:
919:
915:
634:), while others display primary body cavities (deriving from the
524:
493:
100:
75:
7572:
3885:"A merciful death for the 'earliest bilaterian,' Vernanimalcula"
3139:
3088:
2039:
1986:
997:
for Bilateria is shown below, although the positions of certain
574:(tiny "flat animals"). For the most part, bilateral embryos are
7458:
7192:
6392:
6379:
6250:
6247:
5784:
5581:
5311:
5213:
5155:
2778:
2275:
1674:
1159:
962:
927:
692:
673:
539:
509:
405:
164:
4331:
3792:
2970:
2745:
2279:
2096:. The Xenambulacraria may be sister to the Chordata or to the
1868:
1641:
1163:
973:), and the remaining bilaterians. The latter clade was called
439:
370:
6151:
4396:
4211:"Resolving animal phylogeny: A sledgehammer for a tough nut?"
4167:
2159:
1047:
998:
708:
704:
607:
559:
397:
4500:
3929:
3360:
5408:
4792:
3981:
3712:"Back in time: a new systematic proposal for the Bilateria"
3258:
10.1666/0094-8373(2004)030<0203:PODITE>2.0.CO;2
611:
445:
442:
430:
424:
376:
373:
361:
355:
4843:
4646:
4555:
4727:
3709:
676:
or pseudocoelom. Animals with this bilaterally symmetric
4676:
3542:
7182:
3656:
508:
as adults, but are only bilaterally symmetrical as an
4594:
4112:
4110:
457:
448:
418:
385:
349:
3841:
436:
427:
421:
367:
358:
352:
4837:
4595:Smith, Martin R.; Ortega-Hernández, Javier (2014).
3418:
433:
364:
4503:"Xenacoelomorpha is the sister group to Nephrozoa"
4168:Paps, J.; Baguna, J.; Riutort, M. (14 July 2009).
4107:
3793:Fedonkin, M. A.; Waggoner, B. M. (November 1997).
3363:"Xenacoelomorpha is the sister group to Nephrozoa"
4039:Palaeogeography, Palaeoclimatology, Palaeoecology
3445:
7639:
4441:Fröbius, Andreas C.; Funch, Peter (2017-04-04).
843:. Earlier fossils are controversial; the fossil
6104:
4066:
4064:
4062:
4060:
3549:Proceedings of the National Academy of Sciences
115:
4496:
4494:
3501:
3422:Perspectives in Animal Phylogeny and Evolution
527:become concentrated at the front/rostral end.
472:(i.e. having a left and a right side that are
6231:
4941:
4289:(6th ed.). Dubuque, Iowa: Wm. C. Brown.
3876:
3414:
3412:
4955:
4440:
4057:
3923:
3835:
3786:
3609:
3356:
3354:
3321:
3319:
3317:
3315:
530:Bilaterians constitute one of the five main
6618:
5820:
4491:
4314:– via Internet Archive (archive.org).
3842:Bengtson, S.; Budd, G. (19 November 2004).
3236:
3199:Embryological origins of the mouth and anus
953:The traditional division of Bilateria into
6592:
6238:
6224:
4948:
4934:
4436:
4434:
3409:
6785:
5198:
4866:
4820:
4769:
4704:
4694:
4474:
4414:
4373:
4363:
4226:
4185:
3859:
3818:
3752:
3735:
3670:
3586:
3568:
3519:
3351:
3312:
16:Animals with embryonic bilateral symmetry
6652:
6576:Hemichordata (acorn worms and relatives)
6524:
5103:
4209:Telford, Maximilian J. (15 April 2008).
3337:. Sinauer Associates. pp. 345–372.
727:
657:
6377:
6245:
5088:
4431:
4279:
4249:
4208:
4070:
3439:
3425:. Oxford University Press. p. 53.
7640:
6570:Echinodermata (starfish and relatives)
6540:Xenacoelomorpha (acoels and relatives)
6206:denotes groups with over 1,000 species
3495:
3325:
7506:
7505:
6511:
6219:
4929:
4032:
642:) or secondary cavities (that appear
484:are laid around a longitudinal axis (
6841:Acanthocephala (thorny-headed worms)
4909:Tree of Life web project — Bilateria
4562:Organisms, Diversity & Evolution
4033:Verde, Mariano (15 September 2022).
3758:
3975:
3659:Integrative and Comparative Biology
3508:The Journal of Experimental Biology
3446:Finnerty, John R. (November 2005).
13:
6875:
6681:
6438:Cnidaria (jellyfish and relatives)
910:include most of the rest, such as
853:are known from around the time of
111:
14:
7674:
4902:
687:, the development of a head with
7482:Phyla with ≥1000 extant species
4085:10.1111/j.1525-142X.2008.00231.x
3901:10.1111/j.1525-142X.2012.00562.x
3138:
3087:
3065:
3044:
3011:
2969:
2949:
2886:
2866:
2797:
2777:
2744:
2712:
2676:
2656:
2573:
2484:
2460:
2427:
2349:
2329:
2278:
2230:
2158:
2138:
2038:
1985:
1963:
1942:
1909:
1867:
1847:
1782:
1762:
1693:
1673:
1640:
1608:
1572:
1552:
1460:
1371:
1347:
1314:
1257:
1237:
1162:
1114:
1082:
1046:
1026:
817:
751:of all bilateria is termed the "
414:
345:
141:
43:
7663:Taxa named by Berthold Hatschek
4786:
4721:
4670:
4588:
4549:
4403:Molecular Biology and Evolution
4390:
4325:
4243:
4202:
4174:Molecular Biology and Evolution
4161:
4026:
3703:
3650:
3603:
3536:
977:by Jondelius et al. (2002) and
878:List of bilateral animal orders
805:, or the Trochaea by Nielsen).
594:. Except for a few phyla (i.e.
534:lineages, the other four being
7132:
6669:Nematomorpha (horsehair worms)
5685:
5681:
5441:
5437:
3305:Merriam-Webster.com Dictionary
3292:
3285:Merriam-Webster.com Dictionary
3272:
3230:
3211:
1:
6512:
4334:"The mitochondrial genome of
3628:10.1126/science.284.5423.2129
3224:
602:), bilaterians have complete
7281:Echinozoans inc. sea urchins
4228:10.1016/j.devcel.2008.03.016
4051:10.1016/j.palaeo.2022.111158
3419:Minelli, Alessandro (2009).
871:
769:Luitfried von Salvini-Plawen
723:
653:
7:
7658:Ediacaran first appearances
7338:Chelicerates inc. arachnids
7078:Phoronida (horseshoe worms)
6893:Platyhelminthes (flatworms)
6804:Gnathostomulida (jaw worms)
6693:Loricifera (corset animals)
3889:Evolution & Development
3502:Quillin, K. J. (May 1998).
3326:Brusca, Richard C. (2016).
3192:
749:most recent common ancestor
10:
7679:
7228:Medusozoans inc. jellyfish
6974:Annelida (segmented worms)
6799:Chaetognatha (arrow worms)
6715:Onychophora (velvet worms)
4467:10.1038/s41467-017-00020-w
4255:"The Invertebrate Animals"
3770:Cambridge University Press
3237:Grazhdankin, Dima (2004).
890:traditionally include the
875:
794:, the Bilaterosgastrea by
740:
7514:
7478:
7276:Asterozoans inc. starfish
7178:
7171:
7122:
7073:Brachiopoda (lamp shells)
7063:
7054:Ectoprocta (moss animals)
7038:
7029:
7014:
7005:
6990:
6983:
6959:
6948:
6907:
6899:Gastrotricha (hairybacks)
6882:
6871:
6860:
6812:
6794:
6781:
6770:
6723:
6710:
6701:
6688:
6677:
6645:
6628:Kinorhyncha (mud dragons)
6614:
6603:
6588:
6564:
6555:
6535:
6520:
6507:
6472:
6447:
6423:
6408:
6400:Ctenophora (comb jellies)
6388:
6373:
6257:
6182:
6150:
6127:
6054:
6023:
5983:
5954:
5934:
5925:
5913:
5909:
5754:
5745:
5716:
5701:
5692:
5679:
5675:
5608:
5580:
5565:
5556:
5515:
5494:
5485:
5448:
5435:
5431:
5418:
5405:
5401:
5378:
5358:
5354:
5350:
5296:
5283:
5274:
5241:
5228:
5194:
5183:
5165:
5152:
5099:
5084:
5080:
4964:
4868:21.11116/0000-0004-DC4B-1
4859:10.1016/j.cub.2019.04.009
4696:10.1186/s40851-015-0017-0
4574:10.1007/s13127-011-0044-4
3131:
3080:
3059:
3039:
3031:
3005:
2998:
2964:
2943:
2935:
2923:
2881:
2861:
2853:
2792:
2772:
2764:
2739:
2732:
2707:
2700:
2671:
2651:
2643:
2631:
2623:
2611:
2567:
2551:
2543:
2525:
2517:
2475:
2455:
2447:
2422:
2415:
2403:
2364:
2344:
2324:
2316:
2273:
2258:
2250:
2225:
2218:
2206:
2185:
2178:
2153:
2133:
2126:
2029:
1978:
1957:
1937:
1929:
1903:
1896:
1862:
1841:
1833:
1821:
1777:
1757:
1749:
1688:
1668:
1660:
1635:
1628:
1603:
1596:
1567:
1547:
1539:
1527:
1519:
1507:
1454:
1438:
1430:
1412:
1404:
1362:
1342:
1334:
1309:
1302:
1272:
1252:
1232:
1224:
1212:
1200:
1157:
1142:
1134:
1109:
1102:
1073:
1066:
1041:
1021:
1014:
826:sediments, and the first
326:
319:
218:
213:
138:Scientific classification
136:
131:
110:
23:
6834:Rotifera (wheel animals)
6633:Priapulida (penis worms)
5411:
5407:
3204:
614:. Some bilaterians lack
7048:Entoprocta or Kamptozoa
7020:Nemertea (ribbon worms)
6741:Tardigrada (waterbears)
6734:Arthropoda (arthropods)
4365:10.1073/pnas.0400941101
4139:10.1126/science.7886451
4004:10.1126/science.1216295
3953:10.1126/science.1133129
3861:10.1126/science.1101338
3570:10.1073/pnas.2001045117
3521:10.1242/jeb.201.12.1871
2914:> 539 Mya
1810:> 539 Mya
862: million years ago
841: million years ago
7223:Anthozoans inc. corals
6922:Dicyemida or Rhombozoa
4813:10.1098/rstb.2007.2233
4754:10.1126/sciadv.abe2741
3728:10.1098/rstb.2007.2238
2530:Saccorhytus coronarius
1417:Saccorhytus coronarius
938:(molting animals) and
738:
668:
476:of each other) during
126:
7620:Paleobiology Database
7353:Hexapods inc. insects
6663:Nematoda (roundworms)
4658:Palaeos (palaeos.com)
4447:Nature Communications
4416:10.1093/molbev/msh229
4187:10.1093/molbev/msp150
830:bilaterian fossil is
731:
661:
478:embryonic development
132:Bilaterian diversity
125:
6546:Chordata (chordates)
4853:(11): 1818–1826.e6.
3681:10.1093/icb/43.1.137
986:, together with the
697:hydrostatic skeleton
506:pentaradial symmetry
468:), characterized by
6996:Mollusca (molluscs)
6481:of the animal root
6083:Gunflint microbiota
5844:Klebsormidiophyceae
5628:Hyphochytriomycetes
4807:(1496): 1435–1443.
4746:2021SciA....7.2741K
4624:10.1038/nature13576
4616:2014Natur.514..363S
4527:10.1038/nature16520
4519:2016Natur.530...89C
4459:2017NatCo...8....9F
4356:2004PNAS..10110639H
4350:(29): 10639–10643.
4131:1995Sci...267.1641H
4125:(5204): 1641–1643.
3996:2012Sci...336.1693P
3990:(6089): 1693–1696.
3945:2006Sci...314..291H
3811:1997Natur.388..868F
3722:(1496): 1481–1491.
3622:(5423): 2129–2137.
3561:2020PNAS..117.7845E
3387:10.1038/nature16520
3379:2016Natur.530...89C
993:A modern consensus
942:. The arrow worms (
480:. This means their
7209:Calcareous sponges
6394:Porifera (sponges)
5854:Coleochaetophyceae
5234:
5230:
5158:
5154:
4914:2020-11-16 at the
4683:Zoological Letters
4336:Paraspadella gotoi
4215:Developmental Cell
3610:Knoll, Andrew H.;
3467:10.1002/bies.20299
3308:. Merriam-Webster.
3288:. Merriam-Webster.
902:, and the extinct
739:
669:
665:peristaltic motion
646:, for example the
504:, which extend to
470:bilateral symmetry
127:
7635:
7634:
7508:Taxon identifiers
7499:
7498:
7474:
7473:
7167:
7166:
7163:
7162:
7118:
7117:
7114:
7113:
7110:
7109:
7106:
7105:
7102:
7101:
7098:
7097:
7094:
7093:
7090:
7089:
7086:
7085:
6944:
6943:
6940:
6939:
6856:
6855:
6852:
6851:
6766:
6765:
6762:
6761:
6758:
6757:
6754:
6753:
6750:
6749:
6641:
6640:
6584:
6583:
6503:
6502:
6468:
6467:
6464:
6463:
6213:
6212:
6178:
6177:
6114:Spironematellidae
6095:Meteora sporadica
6050:
6049:
6046:
6045:
5979:
5978:
5905:
5904:
5901:
5900:
5897:
5896:
5893:
5892:
5889:
5888:
5885:
5884:
5881:
5880:
5877:
5876:
5805:Prasinodermophyta
5741:
5740:
5671:
5670:
5667:
5666:
5663:
5662:
5659:
5658:
5655:
5654:
5552:
5551:
5388:Centroplasthelida
5346:
5345:
5342:
5341:
5338:
5337:
5334:
5333:
5330:
5329:
5326:
5325:
5322:
5321:
5224:
5223:
5148:
5147:
4610:(7522): 363–366.
4409:(11): 2122–2129.
4180:(10): 2397–2406.
3939:(5797): 291–294.
3805:(6645): 868–871.
3779:978-1-107-62139-8
3555:(14): 7845–7850.
3461:(11): 1174–1180.
3432:978-0-19-856620-5
3344:978-1-60535-375-3
3189:
3188:
3180:
3179:
3171:
3170:
3161:
3160:
3151:
3150:
3120:
3119:
3110:
3109:
3100:
3099:
2982:
2981:
2908:
2907:
2899:
2898:
2837:
2836:
2828:
2827:
2819:
2818:
2810:
2809:
2689:
2688:
2595:
2594:
2586:
2585:
2506:
2505:
2497:
2496:
2387:
2386:
2378:
2377:
2300:
2299:
2291:
2290:
2089:
2088:
2080:
2079:
2071:
2070:
2061:
2060:
2051:
2050:
2018:
2017:
2008:
2007:
1998:
1997:
1880:
1879:
1804:
1803:
1795:
1794:
1733:
1732:
1724:
1723:
1715:
1714:
1706:
1705:
1585:
1584:
1491:
1490:
1482:
1481:
1473:
1472:
1393:
1392:
1384:
1383:
1286:
1285:
1184:
1183:
1175:
1174:
995:phylogenetic tree
969:(together called
866:Tacuarí Formation
747:The hypothetical
720:body structures.
338:
337:
333:
209:
7670:
7628:
7627:
7615:
7614:
7602:
7601:
7589:
7588:
7576:
7575:
7563:
7562:
7550:
7549:
7548:
7535:
7534:
7533:
7503:
7502:
7180:
7179:
7136:
7036:
7035:
7012:
7011:
6988:
6987:
6957:
6956:
6953:
6880:
6879:
6873:
6872:
6869:
6868:
6865:
6792:
6791:
6783:
6782:
6779:
6778:
6775:
6708:
6707:
6686:
6685:
6679:
6678:
6650:
6649:
6616:
6615:
6612:
6611:
6608:
6601:
6600:
6597:
6590:
6589:
6562:
6561:
6533:
6532:
6529:
6522:
6521:
6509:
6508:
6486:
6421:
6420:
6386:
6385:
6382:
6375:
6374:
6286:
6266:
6240:
6233:
6226:
6217:
6216:
6160:Collodictyonidae
6106:Hemimastigophora
6102:
6101:
6061:
5932:
5931:
5923:
5922:
5919:
5911:
5910:
5860:Zygnematophyceae
5818:
5817:
5798:
5782:
5781:
5752:
5751:
5699:
5698:
5690:
5689:
5686:
5677:
5676:
5563:
5562:
5492:
5491:
5446:
5445:
5442:
5433:
5432:
5416:
5415:
5412:
5403:
5402:
5376:
5375:
5363:
5356:
5355:
5352:
5351:
5306:Choanoflagellata
5281:
5280:
5239:
5238:
5235:
5196:
5195:
5192:
5191:
5188:
5163:
5162:
5159:
5101:
5100:
5097:
5096:
5093:
5086:
5085:
5082:
5081:
4993:
4973:
4950:
4943:
4936:
4927:
4926:
4897:
4896:
4870:
4841:
4835:
4834:
4824:
4790:
4784:
4783:
4773:
4740:(12): eabe2741.
4734:Science Advances
4725:
4719:
4718:
4708:
4698:
4674:
4668:
4667:
4665:
4664:
4650:
4644:
4643:
4601:
4592:
4586:
4585:
4553:
4547:
4546:
4498:
4489:
4488:
4478:
4438:
4429:
4428:
4418:
4394:
4388:
4387:
4377:
4367:
4329:
4323:
4315:
4313:
4311:
4281:Kimball, John W.
4269:
4267:
4266:
4253:(3 March 2010).
4251:Kimball, John W.
4247:
4241:
4240:
4230:
4206:
4200:
4199:
4189:
4165:
4159:
4158:
4114:
4105:
4104:
4068:
4055:
4054:
4030:
4024:
4023:
3979:
3973:
3972:
3927:
3921:
3920:
3880:
3874:
3873:
3863:
3839:
3833:
3832:
3822:
3790:
3784:
3783:
3756:
3750:
3749:
3739:
3707:
3701:
3700:
3674:
3654:
3648:
3647:
3612:Carroll, Sean B.
3607:
3601:
3600:
3590:
3572:
3540:
3534:
3533:
3523:
3499:
3493:
3492:
3490:
3489:
3483:
3477:. Archived from
3452:
3443:
3437:
3436:
3416:
3407:
3406:
3358:
3349:
3348:
3332:
3323:
3310:
3309:
3296:
3290:
3289:
3276:
3270:
3269:
3243:
3234:
3218:
3215:
3142:
3091:
3069:
3048:
3034:
3033:
3015:
3001:
3000:
2973:
2953:
2938:
2937:
2926:
2925:
2890:
2870:
2856:
2855:
2801:
2781:
2767:
2766:
2748:
2735:
2734:
2716:
2703:
2702:
2680:
2660:
2646:
2645:
2634:
2633:
2626:
2625:
2614:
2613:
2577:
2546:
2545:
2520:
2519:
2488:
2464:
2450:
2449:
2431:
2418:
2417:
2406:
2405:
2353:
2333:
2319:
2318:
2282:
2261:Nemertodermatida
2253:
2252:
2234:
2221:
2220:
2209:
2208:
2181:
2180:
2162:
2142:
2129:
2128:
2117:
2116:
2042:
1989:
1967:
1946:
1932:
1931:
1913:
1899:
1898:
1871:
1851:
1836:
1835:
1824:
1823:
1786:
1766:
1752:
1751:
1697:
1677:
1663:
1662:
1644:
1631:
1630:
1612:
1599:
1598:
1576:
1556:
1542:
1541:
1530:
1529:
1522:
1521:
1510:
1509:
1464:
1433:
1432:
1407:
1406:
1375:
1351:
1337:
1336:
1318:
1305:
1304:
1261:
1241:
1227:
1226:
1215:
1214:
1203:
1202:
1166:
1145:Nemertodermatida
1137:
1136:
1118:
1105:
1104:
1086:
1069:
1068:
1050:
1030:
1017:
1016:
1005:
1004:
967:Nemertodermatida
863:
842:
804:
777:
761:Elie Metchnikoff
757:Ludwig von Graff
734:Ikaria wariootia
707:which swim with
606:with a separate
604:digestive tracts
464:
460:
455:
454:
451:
450:
447:
444:
441:
438:
435:
432:
429:
426:
423:
420:
392:
388:
383:
382:
379:
378:
375:
372:
369:
366:
363:
360:
357:
354:
351:
331:
204:
146:
145:
114:
105:
42:
27:Temporal range:
21:
20:
7678:
7677:
7673:
7672:
7671:
7669:
7668:
7667:
7638:
7637:
7636:
7631:
7623:
7618:
7610:
7605:
7597:
7592:
7584:
7579:
7571:
7566:
7558:
7553:
7544:
7543:
7538:
7529:
7528:
7523:
7510:
7500:
7495:
7470:
7396:Phylactolaemata
7184:
7174:
7173:
7159:
7150:Xenambulacraria
7126:
7082:
7059:
7025:
7007:Kryptotrochozoa
7001:
6979:
6949:
6936:
6927:Monoblastozoa (
6903:
6861:
6848:
6820:Micrognathozoa
6808:
6771:
6746:
6719:
6697:
6673:
6637:
6604:
6593:
6580:
6551:
6525:
6516:
6499:
6476:
6460:
6443:
6412:
6404:
6378:
6369:
6368:
6284:
6262:
6253:
6244:
6214:
6209:
6174:
6146:
6137:Ancyromonadidae
6123:
6100:
6055:
6042:
6033:Malawimonadidae
6019:
5975:
5950:
5914:
5873:
5816:
5789:
5788:
5780:
5737:
5712:
5680:
5651:
5604:
5576:
5548:
5511:
5481:
5436:
5427:
5406:
5397:
5374:
5359:
5318:
5292:
5270:
5229:
5220:
5184:
5179:
5153:
5144:
5089:
5076:
5075:
4991:
4969:
4960:
4954:
4916:Wayback Machine
4905:
4900:
4847:Current Biology
4842:
4838:
4791:
4787:
4726:
4722:
4675:
4671:
4662:
4660:
4652:
4651:
4647:
4599:
4593:
4589:
4554:
4550:
4513:(7588): 89–93.
4499:
4492:
4439:
4432:
4395:
4391:
4330:
4326:
4309:
4307:
4297:
4264:
4262:
4248:
4244:
4207:
4203:
4166:
4162:
4115:
4108:
4069:
4058:
4031:
4027:
3980:
3976:
3928:
3924:
3881:
3877:
3854:(5700): 1291a.
3840:
3836:
3791:
3787:
3780:
3757:
3753:
3708:
3704:
3672:10.1.1.560.8727
3655:
3651:
3608:
3604:
3541:
3537:
3514:(12): 1871–83.
3500:
3496:
3487:
3485:
3481:
3450:
3444:
3440:
3433:
3417:
3410:
3373:(7588): 89–93.
3359:
3352:
3345:
3330:
3324:
3313:
3298:
3297:
3293:
3278:
3277:
3273:
3241:
3235:
3231:
3227:
3222:
3221:
3216:
3212:
3207:
3195:
3190:
3181:
3172:
3162:
3152:
3121:
3111:
3101:
3008:Platyhelminthes
2983:
2909:
2900:
2838:
2829:
2820:
2811:
2690:
2596:
2587:
2507:
2498:
2425:Cephalochordata
2388:
2379:
2301:
2292:
2214:Xenacoelomorpha
2202:Xenambulacraria
2094:Xenambulacraria
2090:
2081:
2072:
2062:
2052:
2019:
2009:
1999:
1906:Platyhelminthes
1881:
1805:
1796:
1734:
1725:
1716:
1707:
1586:
1492:
1483:
1474:
1394:
1385:
1312:Cephalochordata
1287:
1185:
1176:
1098:Xenacoelomorpha
984:Xenacoelomorpha
880:
874:
858:
837:
820:
798:
796:Gösta Jägersten
771:
745:
726:
716:have extremely
714:parasitic worms
656:
632:Gnathostomulida
624:Platyhelminthes
600:gnathostomulids
578:, having three
462:
458:
417:
413:
390:
386:
348:
344:
332:Lankester, 1873
283:Xenacoelomorpha
277:Xenambulacraria
237:Xenacoelomorpha
231:Xenambulacraria
203:
140:
124:
112:
106:
104:
103:
98:
93:
88:
83:
78:
73:
68:
63:
58:
53:
48:
37:
36:
25:
17:
12:
11:
5:
7676:
7666:
7665:
7660:
7655:
7650:
7633:
7632:
7630:
7629:
7616:
7603:
7590:
7577:
7564:
7551:
7536:
7520:
7518:
7512:
7511:
7497:
7496:
7494:
7493:
7486:
7479:
7476:
7475:
7472:
7471:
7469:
7468:
7467:
7466:
7461:
7456:
7451:
7446:
7434:
7433:
7432:
7427:
7422:
7410:
7409:
7408:
7403:
7398:
7386:
7385:
7384:
7379:
7374:
7369:
7361:Platyhelminths
7357:
7356:
7355:
7350:
7345:
7340:
7328:
7327:
7326:
7321:
7316:
7304:
7303:
7302:
7297:
7285:
7284:
7283:
7278:
7273:
7261:
7260:
7259:
7254:
7249:
7237:
7236:
7235:
7230:
7225:
7213:
7212:
7211:
7206:
7201:
7188:
7186:
7176:
7175:
7172:
7169:
7168:
7165:
7164:
7161:
7160:
7158:
7157:
7155:Centroneuralia
7152:
7147:
7142:
7137:
7123:
7120:
7119:
7116:
7115:
7112:
7111:
7108:
7107:
7104:
7103:
7100:
7099:
7096:
7095:
7092:
7091:
7088:
7087:
7084:
7083:
7081:
7080:
7075:
7069:
7067:
7061:
7060:
7058:
7057:
7050:
7044:
7042:
7033:
7027:
7026:
7024:
7023:
7015:
7009:
7003:
7002:
7000:
6999:
6991:
6985:
6981:
6980:
6978:
6977:
6970:
6960:
6954:
6951:Lophotrochozoa
6946:
6945:
6942:
6941:
6938:
6937:
6935:
6934:
6924:
6919:
6913:
6911:
6905:
6904:
6902:
6901:
6896:
6888:
6886:
6877:
6866:
6863:Platytrochozoa
6858:
6857:
6854:
6853:
6850:
6849:
6847:
6846:
6845:
6844:
6837:
6825:
6822:(Limnognathia)
6816:
6814:
6810:
6809:
6807:
6806:
6801:
6795:
6789:
6776:
6768:
6767:
6764:
6763:
6760:
6759:
6756:
6755:
6752:
6751:
6748:
6747:
6745:
6744:
6737:
6729:
6727:
6721:
6720:
6718:
6717:
6711:
6705:
6699:
6698:
6696:
6695:
6689:
6683:
6675:
6674:
6672:
6671:
6666:
6658:
6656:
6647:
6643:
6642:
6639:
6638:
6636:
6635:
6630:
6624:
6622:
6609:
6598:
6586:
6585:
6582:
6581:
6579:
6578:
6573:
6565:
6559:
6553:
6552:
6550:
6549:
6542:
6536:
6530:
6518:
6517:
6505:
6504:
6501:
6500:
6498:
6497:
6492:
6487:
6473:
6470:
6469:
6466:
6465:
6462:
6461:
6459:
6458:
6454:
6452:
6451:(Triploblasts)
6445:
6444:
6442:
6441:
6434:
6432:and relatives)
6424:
6418:
6406:
6405:
6403:
6402:
6397:
6389:
6383:
6371:
6370:
6367:
6366:
6365:
6364:
6363:
6362:
6359:Mesomycetozoea
6356:
6351:
6341:
6331:
6330:
6329:
6324:
6319:
6314:
6309:
6308:
6307:
6295:Diaphoretickes
6292:
6287:
6282:
6277:
6272:
6267:
6259:
6258:
6255:
6254:
6243:
6242:
6235:
6228:
6220:
6211:
6210:
6208:
6207:
6201:
6194:
6190:excluded from
6183:
6180:
6179:
6176:
6175:
6173:
6172:
6167:
6162:
6156:
6154:
6148:
6147:
6145:
6144:
6142:Planomonadidae
6139:
6133:
6131:
6129:Ancyromonadida
6125:
6124:
6122:
6121:
6119:Paramastigidae
6116:
6110:
6108:
6099:
6098:
6091:
6085:
6079:
6071:
6064:
6062:
6058:Incertae sedis
6052:
6051:
6048:
6047:
6044:
6043:
6041:
6040:
6035:
6029:
6027:
6021:
6020:
6018:
6017:
6012:
6007:
6002:
5997:
5989:
5987:
5981:
5980:
5977:
5976:
5974:
5973:
5966:
5960:
5958:
5952:
5951:
5949:
5948:
5941:
5935:
5929:
5920:
5907:
5906:
5903:
5902:
5899:
5898:
5895:
5894:
5891:
5890:
5887:
5886:
5883:
5882:
5879:
5878:
5875:
5874:
5872:
5871:
5863:
5856:
5851:
5846:
5841:
5834:
5826:
5824:
5815:
5814:
5807:
5801:
5799:
5779:
5778:
5771:
5766:
5761:
5755:
5749:
5747:Archaeplastida
5743:
5742:
5739:
5738:
5736:
5735:
5730:
5722:
5720:
5714:
5713:
5711:
5710:
5702:
5696:
5687:
5673:
5672:
5669:
5668:
5665:
5664:
5661:
5660:
5657:
5656:
5653:
5652:
5650:
5649:
5644:
5637:
5630:
5625:
5620:
5614:
5612:
5606:
5605:
5603:
5602:
5597:
5592:
5586:
5584:
5578:
5577:
5575:
5574:
5566:
5560:
5554:
5553:
5550:
5549:
5547:
5546:
5541:
5538:Dinoflagellata
5534:
5532:Chrompodellida
5529:
5521:
5519:
5513:
5512:
5510:
5509:
5502:
5495:
5489:
5483:
5482:
5480:
5479:
5472:
5465:
5460:
5454:
5452:
5443:
5429:
5428:
5426:
5425:
5419:
5413:
5399:
5398:
5396:
5395:
5390:
5384:
5382:
5373:
5372:
5366:
5364:
5361:Diaphoretickes
5348:
5347:
5344:
5343:
5340:
5339:
5336:
5335:
5332:
5331:
5328:
5327:
5324:
5323:
5320:
5319:
5317:
5316:
5308:
5302:
5300:
5294:
5293:
5291:
5290:
5284:
5278:
5272:
5271:
5269:
5268:
5263:
5258:
5250:
5242:
5236:
5226:
5225:
5222:
5221:
5219:
5218:
5210:
5204:
5202:
5189:
5181:
5180:
5178:
5177:
5172:
5166:
5160:
5150:
5149:
5146:
5145:
5143:
5142:
5137:
5132:
5127:
5120:
5115:
5109:
5107:
5094:
5078:
5077:
5074:
5073:
5072:
5071:
5070:
5069:
5066:Mesomycetozoea
5063:
5058:
5048:
5038:
5037:
5036:
5031:
5026:
5021:
5016:
5015:
5014:
5002:Diaphoretickes
4999:
4994:
4989:
4984:
4979:
4974:
4966:
4965:
4962:
4961:
4959:classification
4953:
4952:
4945:
4938:
4930:
4924:
4923:
4918:
4904:
4903:External links
4901:
4899:
4898:
4836:
4785:
4720:
4669:
4645:
4587:
4568:(2): 151–172.
4548:
4490:
4430:
4389:
4324:
4295:
4278:
4277:
4242:
4221:(4): 457–459.
4201:
4160:
4106:
4079:(2): 241–257.
4056:
4025:
3974:
3922:
3895:(5): 421–427.
3875:
3834:
3785:
3778:
3772:. p. 11.
3760:Held, Lewis I.
3751:
3702:
3665:(1): 137–147.
3649:
3602:
3535:
3494:
3438:
3431:
3408:
3350:
3343:
3311:
3291:
3271:
3252:(2): 203–221.
3228:
3226:
3223:
3220:
3219:
3209:
3208:
3206:
3203:
3202:
3201:
3194:
3191:
3187:
3186:
3183:
3182:
3178:
3177:
3174:
3173:
3169:
3168:
3164:
3163:
3159:
3158:
3154:
3153:
3149:
3148:
3145:
3144:
3130:
3127:
3126:
3123:
3122:
3118:
3117:
3113:
3112:
3108:
3107:
3103:
3102:
3098:
3097:
3094:
3093:
3079:
3076:
3075:
3072:
3071:
3058:
3055:
3054:
3051:
3050:
3038:
3032:
3030:
3027:Lophotrochozoa
3022:
3021:
3018:
3017:
3004:
2999:
2997:
2994:Platytrochozoa
2989:
2988:
2985:
2984:
2980:
2979:
2976:
2975:
2963:
2960:
2959:
2956:
2955:
2942:
2936:
2934:
2924:
2922:
2916:
2915:
2911:
2910:
2906:
2905:
2902:
2901:
2897:
2896:
2893:
2892:
2880:
2877:
2876:
2873:
2872:
2860:
2854:
2852:
2844:
2843:
2840:
2839:
2835:
2834:
2831:
2830:
2826:
2825:
2822:
2821:
2817:
2816:
2813:
2812:
2808:
2807:
2804:
2803:
2791:
2788:
2787:
2784:
2783:
2771:
2765:
2763:
2755:
2754:
2751:
2750:
2738:
2733:
2731:
2723:
2722:
2719:
2718:
2706:
2701:
2699:
2696:
2695:
2692:
2691:
2687:
2686:
2683:
2682:
2670:
2667:
2666:
2663:
2662:
2650:
2644:
2642:
2632:
2630:
2624:
2622:
2612:
2610:
2602:
2601:
2598:
2597:
2593:
2592:
2589:
2588:
2584:
2583:
2580:
2579:
2566:
2563:
2562:
2559:
2558:
2550:
2544:
2542:
2539:
2538:
2535:
2534:
2524:
2518:
2516:
2513:
2512:
2509:
2508:
2504:
2503:
2500:
2499:
2495:
2494:
2491:
2490:
2474:
2471:
2470:
2467:
2466:
2454:
2448:
2446:
2438:
2437:
2434:
2433:
2421:
2416:
2414:
2404:
2402:
2399:Centroneuralia
2394:
2393:
2390:
2389:
2385:
2384:
2381:
2380:
2376:
2375:
2372:
2371:
2363:
2360:
2359:
2356:
2355:
2343:
2340:
2339:
2336:
2335:
2323:
2317:
2315:
2307:
2306:
2303:
2302:
2298:
2297:
2294:
2293:
2289:
2288:
2285:
2284:
2272:
2269:
2268:
2265:
2264:
2257:
2251:
2249:
2241:
2240:
2237:
2236:
2228:Xenoturbellida
2224:
2219:
2217:
2207:
2205:
2197:
2196:
2193:
2192:
2184:
2179:
2177:
2169:
2168:
2165:
2164:
2152:
2149:
2148:
2145:
2144:
2132:
2127:
2125:
2115:
2098:Centroneuralia
2087:
2086:
2083:
2082:
2078:
2077:
2074:
2073:
2069:
2068:
2064:
2063:
2059:
2058:
2054:
2053:
2049:
2048:
2045:
2044:
2028:
2025:
2024:
2021:
2020:
2016:
2015:
2011:
2010:
2006:
2005:
2001:
2000:
1996:
1995:
1992:
1991:
1977:
1974:
1973:
1970:
1969:
1956:
1953:
1952:
1949:
1948:
1936:
1930:
1928:
1925:Lophotrochozoa
1920:
1919:
1916:
1915:
1902:
1897:
1895:
1892:Platytrochozoa
1887:
1886:
1883:
1882:
1878:
1877:
1874:
1873:
1861:
1858:
1857:
1854:
1853:
1840:
1834:
1832:
1822:
1820:
1812:
1811:
1807:
1806:
1802:
1801:
1798:
1797:
1793:
1792:
1789:
1788:
1776:
1773:
1772:
1769:
1768:
1756:
1750:
1748:
1740:
1739:
1736:
1735:
1731:
1730:
1727:
1726:
1722:
1721:
1718:
1717:
1713:
1712:
1709:
1708:
1704:
1703:
1700:
1699:
1687:
1684:
1683:
1680:
1679:
1667:
1661:
1659:
1651:
1650:
1647:
1646:
1634:
1629:
1627:
1619:
1618:
1615:
1614:
1602:
1597:
1595:
1592:
1591:
1588:
1587:
1583:
1582:
1579:
1578:
1566:
1563:
1562:
1559:
1558:
1546:
1540:
1538:
1528:
1526:
1520:
1518:
1508:
1506:
1498:
1497:
1494:
1493:
1489:
1488:
1485:
1484:
1480:
1479:
1476:
1475:
1471:
1470:
1467:
1466:
1453:
1450:
1449:
1446:
1445:
1437:
1431:
1429:
1426:
1425:
1422:
1421:
1411:
1405:
1403:
1400:
1399:
1396:
1395:
1391:
1390:
1387:
1386:
1382:
1381:
1378:
1377:
1361:
1358:
1357:
1354:
1353:
1341:
1335:
1333:
1325:
1324:
1321:
1320:
1308:
1303:
1301:
1293:
1292:
1289:
1288:
1284:
1283:
1280:
1279:
1271:
1268:
1267:
1264:
1263:
1251:
1248:
1247:
1244:
1243:
1231:
1225:
1223:
1213:
1211:
1201:
1199:
1191:
1190:
1187:
1186:
1182:
1181:
1178:
1177:
1173:
1172:
1169:
1168:
1156:
1153:
1152:
1149:
1148:
1141:
1135:
1133:
1125:
1124:
1121:
1120:
1112:Xenoturbellida
1108:
1103:
1101:
1093:
1092:
1089:
1088:
1072:
1067:
1065:
1057:
1056:
1053:
1052:
1040:
1037:
1036:
1033:
1032:
1020:
1015:
1013:
1003:
988:xenoturbellids
873:
870:
855:Vernanimalcula
851:Fossil embryos
846:Vernanimalcula
819:
816:
741:Main article:
725:
722:
655:
652:
336:
335:
324:
323:
317:
316:
315:
314:
313:
312:
311:
310:
305:
295:
294:
293:
292:
291:
286:
274:
263:
247:
246:
245:
239:
228:
216:
215:
211:
210:
198:
191:
190:
185:
178:
177:
172:
168:
167:
162:
158:
157:
152:
148:
147:
134:
133:
129:
128:
108:
107:
99:
94:
89:
84:
79:
74:
69:
64:
59:
54:
49:
44:
26:
15:
9:
6:
4:
3:
2:
7675:
7664:
7661:
7659:
7656:
7654:
7651:
7649:
7646:
7645:
7643:
7626:
7621:
7617:
7613:
7608:
7604:
7600:
7595:
7591:
7587:
7582:
7578:
7574:
7569:
7565:
7561:
7556:
7552:
7547:
7541:
7537:
7532:
7526:
7522:
7521:
7519:
7517:
7513:
7509:
7504:
7491:
7490:dubious phyla
7487:
7485:
7481:
7480:
7477:
7465:
7462:
7460:
7457:
7455:
7452:
7450:
7447:
7445:
7442:
7441:
7440:
7439:
7435:
7431:
7428:
7426:
7423:
7421:
7418:
7417:
7416:
7415:
7411:
7407:
7404:
7402:
7399:
7397:
7394:
7393:
7392:
7391:
7387:
7383:
7380:
7378:
7375:
7373:
7370:
7368:
7365:
7364:
7363:
7362:
7358:
7354:
7351:
7349:
7346:
7344:
7341:
7339:
7336:
7335:
7334:
7333:
7329:
7325:
7322:
7320:
7317:
7315:
7312:
7311:
7310:
7309:
7305:
7301:
7298:
7296:
7293:
7292:
7291:
7290:
7289:Hemichordates
7286:
7282:
7279:
7277:
7274:
7272:
7269:
7268:
7267:
7266:
7262:
7258:
7255:
7253:
7250:
7248:
7245:
7244:
7243:
7242:
7238:
7234:
7231:
7229:
7226:
7224:
7221:
7220:
7219:
7218:
7214:
7210:
7207:
7205:
7204:Glass sponges
7202:
7200:
7197:
7196:
7195:
7194:
7190:
7189:
7187:
7181:
7177:
7170:
7156:
7153:
7151:
7148:
7146:
7145:Deuterostomia
7143:
7141:
7138:
7134:
7131:of Bilateria
7130:
7125:
7124:
7121:
7079:
7076:
7074:
7071:
7070:
7068:
7066:
7062:
7056:
7055:
7051:
7049:
7046:
7045:
7043:
7041:
7037:
7034:
7032:
7028:
7022:
7021:
7017:
7016:
7013:
7010:
7008:
7004:
6998:
6997:
6993:
6992:
6989:
6986:
6982:
6976:
6975:
6971:
6969:
6967:
6964:Cycliophora (
6962:
6961:
6958:
6955:
6952:
6947:
6932:
6930:
6925:
6923:
6920:
6918:
6915:
6914:
6912:
6910:
6906:
6900:
6897:
6895:
6894:
6890:
6889:
6887:
6885:
6881:
6878:
6874:
6870:
6867:
6864:
6859:
6843:
6842:
6838:
6836:
6835:
6831:
6830:
6829:
6826:
6824:
6823:
6818:
6817:
6815:
6811:
6805:
6802:
6800:
6797:
6796:
6793:
6790:
6788:
6784:
6780:
6777:
6774:
6769:
6743:
6742:
6738:
6736:
6735:
6731:
6730:
6728:
6726:
6722:
6716:
6713:
6712:
6709:
6706:
6704:
6703:Panarthropoda
6700:
6694:
6691:
6690:
6687:
6684:
6680:
6676:
6670:
6667:
6665:
6664:
6660:
6659:
6657:
6655:
6651:
6648:
6644:
6634:
6631:
6629:
6626:
6625:
6623:
6621:
6617:
6613:
6610:
6607:
6602:
6599:
6596:
6591:
6587:
6577:
6574:
6572:
6571:
6567:
6566:
6563:
6560:
6558:
6554:
6548:
6547:
6543:
6541:
6538:
6537:
6534:
6531:
6528:
6523:
6519:
6515:
6510:
6506:
6496:
6493:
6491:
6488:
6484:
6480:
6475:
6474:
6471:
6456:
6455:
6453:
6450:
6446:
6440:
6439:
6435:
6433:
6431:
6426:
6425:
6422:
6419:
6416:
6411:
6407:
6401:
6398:
6396:
6395:
6391:
6390:
6387:
6384:
6381:
6376:
6372:
6360:
6357:
6355:
6352:
6350:
6347:
6346:
6345:
6342:
6340:
6337:
6336:
6335:
6332:
6328:
6325:
6323:
6322:Stramenopiles
6320:
6318:
6315:
6313:
6310:
6306:
6303:
6302:
6301:
6298:
6297:
6296:
6293:
6291:
6288:
6285:(major groups
6283:
6281:
6278:
6276:
6273:
6271:
6268:
6265:
6261:
6260:
6256:
6252:
6249:
6241:
6236:
6234:
6229:
6227:
6222:
6221:
6218:
6205:
6202:
6199:
6195:
6193:
6189:
6186:¹traditional
6185:
6184:
6181:
6171:
6168:
6166:
6165:Mantamonadida
6163:
6161:
6158:
6157:
6155:
6153:
6149:
6143:
6140:
6138:
6135:
6134:
6132:
6130:
6126:
6120:
6117:
6115:
6112:
6111:
6109:
6107:
6103:
6097:
6096:
6092:
6090:
6086:
6084:
6080:
6078:
6077:
6072:
6070:
6066:
6065:
6063:
6060:
6059:
6053:
6039:
6036:
6034:
6031:
6030:
6028:
6026:
6022:
6016:
6013:
6011:
6008:
6006:
6003:
6001:
5998:
5996:
5995:
5991:
5990:
5988:
5986:
5982:
5972:
5971:
5967:
5965:
5964:Heterolobosea
5962:
5961:
5959:
5957:
5956:Discicristata
5953:
5947:
5946:
5942:
5940:
5937:
5936:
5933:
5930:
5928:
5924:
5921:
5917:
5912:
5908:
5869:
5868:
5864:
5862:
5861:
5857:
5855:
5852:
5850:
5847:
5845:
5842:
5840:
5839:
5835:
5833:
5832:
5828:
5827:
5825:
5823:
5819:
5813:
5812:
5808:
5806:
5803:
5802:
5800:
5796:
5795:
5787:
5786:Viridiplantae
5783:
5777:
5776:
5772:
5770:
5767:
5765:
5762:
5760:
5757:
5756:
5753:
5750:
5748:
5744:
5734:
5731:
5729:
5728:
5724:
5723:
5721:
5719:
5715:
5709:
5708:
5707:Microheliella
5704:
5703:
5700:
5697:
5695:
5691:
5688:
5684:
5678:
5674:
5648:
5647:Actinophryida
5645:
5643:
5642:
5638:
5636:
5635:
5631:
5629:
5626:
5624:
5621:
5619:
5616:
5615:
5613:
5611:
5607:
5601:
5598:
5596:
5593:
5591:
5588:
5587:
5585:
5583:
5579:
5573:
5572:
5568:
5567:
5564:
5561:
5559:
5558:Stramenopiles
5555:
5545:
5542:
5540:
5539:
5535:
5533:
5530:
5528:
5527:
5523:
5522:
5520:
5518:
5514:
5508:
5507:
5503:
5500:
5497:
5496:
5493:
5490:
5488:
5484:
5478:
5477:
5473:
5471:
5470:
5466:
5464:
5461:
5459:
5456:
5455:
5453:
5451:
5447:
5444:
5440:
5434:
5430:
5424:
5421:
5420:
5417:
5414:
5410:
5404:
5400:
5394:
5391:
5389:
5386:
5385:
5383:
5381:
5377:
5371:
5368:
5367:
5365:
5362:
5357:
5353:
5349:
5314:
5313:
5309:
5307:
5304:
5303:
5301:
5299:
5295:
5289:
5286:
5285:
5282:
5279:
5277:
5273:
5267:
5264:
5262:
5261:Ichthyosporea
5259:
5257:
5256:
5251:
5249:
5248:
5244:
5243:
5240:
5237:
5233:
5227:
5216:
5215:
5211:
5209:
5208:Rotosphaerida
5206:
5205:
5203:
5201:
5197:
5193:
5190:
5187:
5182:
5176:
5173:
5171:
5170:Apusomonadida
5168:
5167:
5164:
5161:
5157:
5151:
5141:
5138:
5136:
5133:
5131:
5128:
5126:
5125:
5121:
5119:
5116:
5114:
5111:
5110:
5108:
5106:
5102:
5098:
5095:
5092:
5087:
5083:
5079:
5067:
5064:
5062:
5059:
5057:
5054:
5053:
5052:
5049:
5047:
5044:
5043:
5042:
5039:
5035:
5032:
5030:
5029:Stramenopiles
5027:
5025:
5022:
5020:
5017:
5013:
5010:
5009:
5008:
5005:
5004:
5003:
5000:
4998:
4995:
4992:(major groups
4990:
4988:
4985:
4983:
4980:
4978:
4975:
4972:
4968:
4967:
4963:
4958:
4951:
4946:
4944:
4939:
4937:
4932:
4931:
4928:
4922:
4919:
4917:
4913:
4910:
4907:
4906:
4894:
4890:
4886:
4882:
4878:
4874:
4869:
4864:
4860:
4856:
4852:
4848:
4840:
4832:
4828:
4823:
4818:
4814:
4810:
4806:
4802:
4801:
4796:
4789:
4781:
4777:
4772:
4767:
4763:
4759:
4755:
4751:
4747:
4743:
4739:
4735:
4731:
4724:
4716:
4712:
4707:
4702:
4697:
4692:
4688:
4684:
4680:
4673:
4659:
4655:
4649:
4641:
4637:
4633:
4629:
4625:
4621:
4617:
4613:
4609:
4605:
4598:
4591:
4583:
4579:
4575:
4571:
4567:
4563:
4559:
4552:
4544:
4540:
4536:
4532:
4528:
4524:
4520:
4516:
4512:
4508:
4504:
4497:
4495:
4486:
4482:
4477:
4472:
4468:
4464:
4460:
4456:
4452:
4448:
4444:
4437:
4435:
4426:
4422:
4417:
4412:
4408:
4404:
4400:
4393:
4385:
4381:
4376:
4371:
4366:
4361:
4357:
4353:
4349:
4345:
4344:
4339:
4337:
4328:
4322:
4318:
4306:
4302:
4298:
4292:
4288:
4287:
4282:
4275:
4272:abbridged by
4271:
4270:
4261:on 2010-03-10
4260:
4256:
4252:
4246:
4238:
4234:
4229:
4224:
4220:
4216:
4212:
4205:
4197:
4193:
4188:
4183:
4179:
4175:
4171:
4164:
4156:
4152:
4148:
4144:
4140:
4136:
4132:
4128:
4124:
4120:
4113:
4111:
4102:
4098:
4094:
4090:
4086:
4082:
4078:
4074:
4067:
4065:
4063:
4061:
4052:
4048:
4044:
4040:
4036:
4029:
4021:
4017:
4013:
4009:
4005:
4001:
3997:
3993:
3989:
3985:
3978:
3970:
3966:
3962:
3958:
3954:
3950:
3946:
3942:
3938:
3934:
3926:
3918:
3914:
3910:
3906:
3902:
3898:
3894:
3890:
3886:
3879:
3871:
3867:
3862:
3857:
3853:
3849:
3845:
3838:
3830:
3826:
3821:
3820:10.1038/42242
3816:
3812:
3808:
3804:
3800:
3796:
3789:
3781:
3775:
3771:
3767:
3766:
3761:
3755:
3747:
3743:
3738:
3733:
3729:
3725:
3721:
3717:
3713:
3706:
3698:
3694:
3690:
3686:
3682:
3678:
3673:
3668:
3664:
3660:
3653:
3645:
3641:
3637:
3633:
3629:
3625:
3621:
3617:
3613:
3606:
3598:
3594:
3589:
3584:
3580:
3576:
3571:
3566:
3562:
3558:
3554:
3550:
3546:
3539:
3531:
3527:
3522:
3517:
3513:
3509:
3505:
3498:
3484:on 2019-07-02
3480:
3476:
3472:
3468:
3464:
3460:
3456:
3449:
3442:
3434:
3428:
3424:
3423:
3415:
3413:
3404:
3400:
3396:
3392:
3388:
3384:
3380:
3376:
3372:
3368:
3364:
3357:
3355:
3346:
3340:
3336:
3335:Invertebrates
3329:
3322:
3320:
3318:
3316:
3307:
3306:
3301:
3295:
3287:
3286:
3281:
3275:
3267:
3263:
3259:
3255:
3251:
3247:
3240:
3233:
3229:
3214:
3210:
3200:
3197:
3196:
3185:
3184:
3176:
3175:
3167:650 Mya
3166:
3165:
3157:610 Mya
3156:
3155:
3147:
3146:
3143:
3141:
3136:
3129:
3128:
3125:
3124:
3116:580 Mya
3115:
3114:
3106:550 Mya
3105:
3104:
3096:
3095:
3092:
3090:
3085:
3078:
3077:
3074:
3073:
3070:
3068:
3063:
3057:
3056:
3053:
3052:
3049:
3047:
3043:
3036:
3035:
3028:
3024:
3023:
3020:
3019:
3016:
3014:
3009:
3003:
3002:
2995:
2991:
2990:
2987:
2986:
2978:
2977:
2974:
2972:
2968:
2962:
2961:
2958:
2957:
2954:
2952:
2947:
2940:
2939:
2932:
2928:
2927:
2921:
2918:
2917:
2913:
2912:
2904:
2903:
2895:
2894:
2891:
2889:
2885:
2879:
2878:
2875:
2874:
2871:
2869:
2865:
2858:
2857:
2850:
2846:
2845:
2842:
2841:
2833:
2832:
2824:
2823:
2815:
2814:
2806:
2805:
2802:
2800:
2796:
2790:
2789:
2786:
2785:
2782:
2780:
2776:
2769:
2768:
2761:
2757:
2756:
2753:
2752:
2749:
2747:
2743:
2737:
2736:
2729:
2728:Panarthropoda
2725:
2724:
2721:
2720:
2717:
2715:
2711:
2705:
2704:
2698:
2697:
2694:
2693:
2685:
2684:
2681:
2679:
2675:
2669:
2668:
2665:
2664:
2661:
2659:
2655:
2648:
2647:
2640:
2636:
2635:
2628:
2627:
2620:
2616:
2615:
2608:
2604:
2603:
2600:
2599:
2591:
2590:
2582:
2581:
2578:
2576:
2572:
2571:Vetulicolians
2565:
2564:
2561:
2560:
2557:
2556:
2555:Vetulocystids
2548:
2547:
2541:
2540:
2537:
2536:
2533:
2532:
2531:
2522:
2521:
2515:
2514:
2511:
2510:
2502:
2501:
2493:
2492:
2489:
2487:
2483:
2479:
2473:
2472:
2469:
2468:
2465:
2463:
2459:
2452:
2451:
2444:
2440:
2439:
2436:
2435:
2432:
2430:
2426:
2420:
2419:
2412:
2408:
2407:
2400:
2396:
2395:
2392:
2391:
2383:
2382:
2374:
2373:
2370:
2369:
2362:
2361:
2358:
2357:
2354:
2352:
2348:
2342:
2341:
2338:
2337:
2334:
2332:
2328:
2327:Echinodermata
2321:
2320:
2313:
2309:
2308:
2305:
2304:
2296:
2295:
2287:
2286:
2283:
2281:
2277:
2271:
2270:
2267:
2266:
2263:
2262:
2255:
2254:
2247:
2243:
2242:
2239:
2238:
2235:
2233:
2229:
2223:
2222:
2215:
2211:
2210:
2203:
2199:
2198:
2195:
2194:
2191:
2190:
2189:Proarticulata
2183:
2182:
2175:
2171:
2170:
2167:
2166:
2163:
2161:
2157:
2151:
2150:
2147:
2146:
2143:
2141:
2137:
2131:
2130:
2123:
2119:
2118:
2114:
2111:
2107:
2103:
2099:
2095:
2085:
2084:
2076:
2075:
2067:650 Mya
2066:
2065:
2057:610 mya
2056:
2055:
2047:
2046:
2043:
2041:
2037:
2033:
2027:
2026:
2023:
2022:
2014:580 Mya
2013:
2012:
2004:550 mya
2003:
2002:
1994:
1993:
1990:
1988:
1983:
1976:
1975:
1972:
1971:
1968:
1966:
1961:
1955:
1954:
1951:
1950:
1947:
1945:
1941:
1934:
1933:
1926:
1922:
1921:
1918:
1917:
1914:
1912:
1907:
1901:
1900:
1893:
1889:
1888:
1885:
1884:
1876:
1875:
1872:
1870:
1866:
1860:
1859:
1856:
1855:
1852:
1850:
1845:
1838:
1837:
1830:
1826:
1825:
1818:
1814:
1813:
1809:
1808:
1800:
1799:
1791:
1790:
1787:
1785:
1781:
1775:
1774:
1771:
1770:
1767:
1765:
1761:
1754:
1753:
1746:
1742:
1741:
1738:
1737:
1729:
1728:
1720:
1719:
1711:
1710:
1702:
1701:
1698:
1696:
1692:
1686:
1685:
1682:
1681:
1678:
1676:
1672:
1665:
1664:
1657:
1653:
1652:
1649:
1648:
1645:
1643:
1639:
1633:
1632:
1625:
1624:Panarthropoda
1621:
1620:
1617:
1616:
1613:
1611:
1607:
1601:
1600:
1594:
1593:
1590:
1589:
1581:
1580:
1577:
1575:
1571:
1565:
1564:
1561:
1560:
1557:
1555:
1551:
1544:
1543:
1536:
1532:
1531:
1524:
1523:
1516:
1512:
1511:
1504:
1500:
1499:
1496:
1495:
1487:
1486:
1478:
1477:
1469:
1468:
1465:
1463:
1459:
1458:Vetulicolians
1452:
1451:
1448:
1447:
1444:
1443:
1442:Vetulocystids
1435:
1434:
1428:
1427:
1424:
1423:
1420:
1419:
1418:
1409:
1408:
1402:
1401:
1398:
1397:
1389:
1388:
1380:
1379:
1376:
1374:
1370:
1366:
1360:
1359:
1356:
1355:
1352:
1350:
1346:
1339:
1338:
1331:
1327:
1326:
1323:
1322:
1319:
1317:
1313:
1307:
1306:
1299:
1295:
1294:
1291:
1290:
1282:
1281:
1278:
1277:
1270:
1269:
1266:
1265:
1262:
1260:
1256:
1250:
1249:
1246:
1245:
1242:
1240:
1236:
1235:Echinodermata
1229:
1228:
1221:
1217:
1216:
1209:
1208:Deuterostomia
1205:
1204:
1197:
1193:
1192:
1189:
1188:
1180:
1179:
1171:
1170:
1167:
1165:
1161:
1155:
1154:
1151:
1150:
1147:
1146:
1139:
1138:
1131:
1127:
1126:
1123:
1122:
1119:
1117:
1113:
1107:
1106:
1099:
1095:
1094:
1091:
1090:
1087:
1085:
1081:
1077:
1076:Proarticulata
1071:
1070:
1063:
1059:
1058:
1055:
1054:
1051:
1049:
1045:
1039:
1038:
1035:
1034:
1031:
1029:
1025:
1019:
1018:
1011:
1007:
1006:
1002:
1000:
996:
991:
989:
985:
980:
976:
972:
968:
964:
960:
956:
955:Deuterostomia
951:
949:
945:
941:
937:
933:
929:
925:
921:
917:
913:
909:
905:
901:
897:
896:hemichordates
893:
889:
888:deuterostomes
885:
879:
869:
867:
861:
856:
852:
848:
847:
840:
835:
834:
829:
825:
818:Fossil record
815:
813:
812:
806:
802:
797:
793:
789:
785:
781:
775:
770:
766:
762:
758:
754:
750:
744:
736:
735:
730:
721:
719:
718:plesiomorphic
715:
710:
706:
702:
698:
694:
690:
686:
685:cephalisation
681:
679:
675:
666:
660:
651:
649:
645:
641:
640:pseudocoeloms
637:
633:
629:
625:
621:
617:
616:body cavities
613:
609:
605:
601:
597:
593:
589:
585:
581:
577:
576:triploblastic
573:
569:
565:
561:
557:
553:
549:
545:
541:
537:
533:
528:
526:
523:
522:central nerve
519:
518:special sense
515:
514:Cephalization
511:
507:
503:
499:
495:
491:
487:
483:
479:
475:
474:mirror images
471:
467:
466:
453:
411:
407:
403:
399:
396:) is a large
395:
394:
381:
342:
334:
330:
325:
322:
318:
309:
306:
304:
301:
300:
299:
296:
290:
287:
284:
281:
280:
278:
275:
273:
270:
269:
267:
266:Deuterostomia
264:
262:
259:
258:
254:
253:
251:
248:
243:
240:
238:
235:
234:
232:
229:
227:
223:
222:Proarticulata
220:
219:
217:
214:Subdivisions
212:
207:
202:
199:
196:
193:
192:
189:
186:
183:
180:
179:
176:
173:
170:
169:
166:
163:
160:
159:
156:
153:
150:
149:
144:
139:
135:
130:
109:
102:
97:
92:
87:
82:
77:
72:
67:
62:
57:
52:
47:
41:
34:
30:
22:
19:
7515:
7488:Potentially
7483:
7436:
7412:
7406:Gymnolaemata
7401:Stenolaemata
7390:Ectoproctans
7388:
7359:
7330:
7306:
7300:Pterobranchs
7287:
7263:
7239:
7215:
7191:
7185:within phyla
7183:Major groups
7053:
7040:Bryozoa s.l.
7031:Lophophorata
7019:
6995:
6973:
6965:
6928:
6917:Orthonectida
6892:
6839:
6832:
6821:
6740:
6733:
6662:
6620:Scalidophora
6569:
6557:Ambulacraria
6544:
6526:
6513:
6457:(see below↓)
6448:
6437:
6429:
6393:
6344:Opisthokonta
6203:
6198:paraphyletic
6093:
6074:
6056:
6025:Malawimonada
6005:Anaeromonada
6000:Anaeramoebae
5992:
5968:
5945:Tsukubamonas
5943:
5865:
5858:
5849:Charophyceae
5836:
5829:
5822:Streptophyta
5809:
5793:
5773:
5769:Rhodelphidia
5727:Palpitomonas
5725:
5705:
5694:Pancryptista
5639:
5632:
5569:
5536:
5524:
5504:
5474:
5469:Foraminifera
5467:
5310:
5253:
5247:Tunicaraptor
5245:
5212:
5186:Opisthokonta
5122:
5051:Opisthokonta
4850:
4846:
4839:
4804:
4798:
4788:
4737:
4733:
4723:
4686:
4682:
4672:
4661:. Retrieved
4657:
4648:
4607:
4603:
4590:
4565:
4561:
4551:
4510:
4506:
4450:
4446:
4406:
4402:
4392:
4347:
4341:
4335:
4327:
4308:. Retrieved
4285:
4263:. Retrieved
4259:the original
4245:
4218:
4214:
4204:
4177:
4173:
4163:
4122:
4118:
4076:
4072:
4042:
4038:
4028:
3987:
3983:
3977:
3936:
3932:
3925:
3892:
3888:
3878:
3851:
3847:
3837:
3802:
3798:
3788:
3764:
3754:
3719:
3715:
3705:
3662:
3658:
3652:
3619:
3615:
3605:
3552:
3548:
3538:
3511:
3507:
3497:
3486:. Retrieved
3479:the original
3458:
3454:
3441:
3421:
3370:
3366:
3334:
3303:
3300:"bilaterian"
3294:
3283:
3274:
3249:
3246:Paleobiology
3245:
3232:
3213:
3132:
3081:
3060:
3040:
3006:
2967:Chaetognatha
2965:
2944:
2882:
2862:
2849:Scalidophora
2793:
2773:
2740:
2708:
2674:Nematomorpha
2672:
2652:
2568:
2552:
2528:
2526:
2476:
2456:
2423:
2368:Cambroernida
2365:
2347:Hemichordata
2345:
2325:
2312:Ambulacraria
2274:
2259:
2246:Acoelomorpha
2226:
2186:
2173:
2154:
2134:
2106:sister group
2091:
2030:
1979:
1958:
1938:
1904:
1865:Chaetognatha
1863:
1842:
1778:
1758:
1745:Scalidophora
1689:
1669:
1636:
1604:
1570:Nematomorpha
1568:
1548:
1455:
1439:
1415:
1413:
1363:
1343:
1310:
1276:Cambroernida
1273:
1255:Hemichordata
1253:
1233:
1220:Ambulacraria
1158:
1143:
1130:Acoelomorpha
1110:
1074:
1061:
1042:
1022:
992:
971:Acoelomorpha
952:
944:Chaetognatha
881:
854:
844:
836:, dating to
831:
827:
821:
811:Xenoturbella
809:
807:
784:gastrotrichs
765:Libbie Hyman
753:Urbilaterian
746:
732:
689:sense organs
682:
670:
643:
628:Gastrotricha
568:comb jellies
556:sea anemones
529:
496:) and back (
409:
402:infrakingdom
340:
339:
329:Triploblasts
327:
289:Ambulacraria
255:
242:Ambulacraria
200:
194:
181:
171:Subkingdom:
18:
7653:Subkingdoms
7648:Bilaterians
7581:iNaturalist
7540:Wikispecies
7464:Tusk shells
7449:Cephalopods
7420:Polychaetes
7367:Turbellaria
7348:Crustaceans
7324:Secernentea
7314:Chromadorea
7295:Acorn worms
7265:Echinoderms
7257:Vertebrates
7199:Demosponges
7133:is disputed
6595:Protostomia
6483:is disputed
6410:ParaHoxozoa
6089:Chitinozoan
6015:Parabasalia
5867:Embryophyta
5831:Chlorokybus
5811:Chlorophyta
5759:Glaucophyta
5733:Cryptophyta
5623:Pirsoniales
5590:Bicosoecida
5571:Platysulcus
5544:Perkinsozoa
5526:Apicomplexa
5499:Colponemida
5266:Pluriformea
5135:Archamoebea
5124:Eumycetozoa
4656:. Metazoa.
4654:"Ecdysozoa"
3280:"bilateria"
3064:and allies
3010:and allies
2948:and allies
2884:Kinorhyncha
2742:Onychophora
2607:Protostomia
2458:Urochordata
2122:ParaHoxozoa
2110:Protostomia
1962:and allies
1908:and allies
1846:and allies
1780:Kinorhyncha
1638:Onychophora
1503:Protostomia
1010:ParaHoxozoa
979:Eubilateria
959:Protostomia
932:taxonomists
908:protostomes
904:Vetulicolia
892:echinoderms
799: [
772: [
743:Urbilateria
701:peristalsis
699:to move by
620:acoelomates
580:germ layers
520:organs and
502:echinoderms
410:bilaterians
298:Protostomia
188:ParaHoxozoa
38:567–0
24:Bilaterians
7642:Categories
7444:Gastropods
7425:Clitellata
7332:Arthropods
7271:Sea lilies
7217:Cnidarians
7135:; see also
7065:Brachiozoa
6828:Syndermata
6787:Gnathifera
6485:; see also
6430:Trichoplax
6428:Placozoa (
6415:Planulozoa
6170:Rigifilida
6069:Acritarchs
5994:Barthelona
5985:Metamonada
5970:Euglenozoa
5838:Mesostigma
5794:sensu lato
5775:Rhodophyta
5634:Ochrophyta
5595:Placidozoa
5506:Ciliophora
5476:Radiolaria
5393:Haptophyta
5288:Filasterea
5200:Holomycota
4663:2017-09-02
4321:0697202844
4305:1280752069
4296:0697142574
4265:2006-01-09
3931:Embryos".
3488:2018-03-07
3225:References
3135:Kimberella
3084:Kimberella
2931:Gnathifera
2864:Priapulida
2795:Arthropoda
2775:Tardigrada
2710:Loricifera
2482:Vertebrata
2443:Olfactores
2032:Kimberella
1982:Kimberella
1829:Gnathifera
1760:Priapulida
1691:Arthropoda
1671:Tardigrada
1606:Loricifera
1369:Vertebrata
1330:Olfactores
948:Gnathifera
912:arthropods
884:superphyla
876:See also:
833:Kimberella
636:blastocoel
564:Ctenophora
482:body plans
7560:Bilateria
7546:Bilateria
7516:Bilateria
7430:Sipuncula
7377:Monogenea
7372:Trematoda
7343:Myriapods
7308:Nematodes
7252:Tunicates
7247:Lancelets
7241:Chordates
7233:Myxozoans
7140:Nephrozoa
7129:phylogeny
6929:Salinella
6884:Rouphozoa
6725:Tactopoda
6654:Nematoida
6606:Ecdysozoa
6527:Bilateria
6514:Bilateria
6495:Benthozoa
6490:Eumetazoa
6479:phylogeny
6449:Bilateria
6339:Amoebozoa
6317:Alveolata
6305:Cryptista
6280:Eukaryota
6010:Fornicata
5916:Excavates
5718:Cryptista
5641:Oomycetes
5618:Developea
5600:Sagenista
5487:Alveolata
5423:Telonemia
5298:Choanozoa
5175:Breviatea
5118:Tubulinea
5105:Amoebozoa
5046:Amoebozoa
5024:Alveolata
5012:Cryptista
4987:Eukaryota
4957:Eukaryote
4893:155104811
4877:0960-9822
4762:2375-2548
4640:205239797
4543:205247296
4283:(1994) .
4073:Evol. Dev
3917:205675058
3667:CiteSeerX
3579:0027-8424
3455:BioEssays
3403:205247296
3266:129376371
2760:Tactopoda
2639:Nematoida
2619:Ecdysozoa
2174:Bilateria
1656:Tactopoda
1535:Nematoida
1515:Ecdysozoa
1196:Nephrozoa
1062:Bilateria
975:Nephrozoa
936:Ecdysozoa
924:flatworms
900:chordates
872:Phylogeny
828:bona fide
824:Ediacaran
780:flatworms
724:Evolution
678:body plan
654:Body plan
596:flatworms
548:jellyfish
341:Bilateria
303:Ecdysozoa
250:Nephrozoa
201:Bilateria
175:Eumetazoa
161:Kingdom:
155:Eukaryota
29:Ediacaran
7525:Wikidata
7454:Bivalves
7438:Molluscs
7414:Annelids
6773:Spiralia
6380:Animalia
6334:Amorphea
6312:Rhizaria
6300:Hacrobia
6290:Excavata
6275:Bacteria
6192:protists
6188:kingdoms
6076:Grypania
6038:Imasidae
5939:Jakobida
5463:Endomyxa
5458:Cercozoa
5450:Rhizaria
5380:Haptista
5312:Animalia
5255:Bicellum
5130:Variosea
5113:Discosea
5091:Amorphea
5041:Amorphea
5019:Rhizaria
5007:Hacrobia
4997:Excavata
4982:Bacteria
4912:Archived
4885:31104936
4831:18192191
4780:33741592
4715:26605063
4632:25132546
4582:32169826
4535:26842059
4485:28377584
4453:(1): 9.
4425:15306659
4384:15249679
4237:18410719
4196:19602542
4155:12196991
4093:18315817
4020:27970523
4012:22745427
3969:25112751
3961:17038620
3909:22947315
3870:15550644
3762:(2014).
3746:18192186
3697:80975506
3689:21680418
3636:10381872
3597:32205432
3475:16237677
3395:26842059
3193:See also
3062:Annelida
3042:Mollusca
3037:
3029:
2996:
2946:Rotifera
2941:
2933:
2920:Spiralia
2859:
2851:
2770:
2762:
2730:
2654:Nematoda
2649:
2641:
2629:
2621:
2609:
2549:
2523:
2478:Craniata
2453:
2445:
2413:
2411:Chordata
2401:
2322:
2314:
2256:
2248:
2216:
2204:
2176:
2156:Placozoa
2136:Cnidaria
2124:
2102:Chordata
1960:Annelida
1940:Mollusca
1935:
1927:
1894:
1844:Rotifera
1839:
1831:
1819:
1817:Spiralia
1755:
1747:
1666:
1658:
1626:
1550:Nematoda
1545:
1537:
1525:
1517:
1505:
1436:
1410:
1365:Craniata
1345:Tunicata
1340:
1332:
1300:
1298:Chordata
1230:
1222:
1210:
1198:
1140:
1132:
1100:
1064:
1044:Placozoa
1024:Cnidaria
1012:
940:Spiralia
920:mollusks
916:annelids
792:Sedgwick
592:ectoderm
588:mesoderm
584:endoderm
572:Placozoa
544:Cnidaria
536:Porifera
532:metazoan
321:Synonyms
308:Spiralia
272:Chordata
252: ?
206:Hatschek
165:Animalia
151:Domain:
7573:3014411
7459:Chitons
7382:Cestoda
7319:Enoplea
7193:Sponges
6966:Symbion
6909:Mesozoa
6349:Animals
6270:Archaea
6246:Extant
5927:Discoba
5792:Plants
5764:Picozoa
5610:Gyrista
5517:Myzozoa
5370:Provora
5276:Filozoa
5232:Holozoa
5140:Cutosea
5056:Animals
4977:Archaea
4822:2614224
4771:7978419
4742:Bibcode
4706:4657359
4612:Bibcode
4515:Bibcode
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