Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan
dc.contributor.author | Howard, RJ | |
dc.contributor.author | Edgecombe, GD | |
dc.contributor.author | Shi, X | |
dc.contributor.author | Hou, X | |
dc.contributor.author | Ma, X | |
dc.date.accessioned | 2021-01-19T09:23:58Z | |
dc.date.issued | 2020-11-23 | |
dc.description.abstract | Background: Ecdysozoa are the moulting protostomes, including arthropods, tardigrades, and nematodes. Both the molecular and fossil records indicate that Ecdysozoa is an ancient group originating in the terminal Proterozoic, and exceptional fossil biotas show their dominance and diversity at the beginning of the Phanerozoic. However, the nature of the ecdysozoan common ancestor has been difficult to ascertain due to the extreme morphological diversity of extant Ecdysozoa, and the lack of early diverging taxa in ancient fossil biotas. Results: Here we re-describe Acosmia maotiania from the early Cambrian Chengjiang Biota of Yunnan Province, China and assign it to stem group Ecdysozoa. Acosmia features a two-part body, with an anterior proboscis bearing a terminal mouth and muscular pharynx, and a posterior annulated trunk with a through gut. Morphological phylogenetic analyses of the protostomes using parsimony, maximum likelihood and Bayesian inference, with coding informed by published experimental decay studies, each placed Acosmia as sister taxon to Cycloneuralia + Panarthropoda—i.e. stem group Ecdysozoa. Ancestral state probabilities were calculated for key ecdysozoan nodes, in order to test characters inferred from fossils to be ancestral for Ecdysozoa. Results support an ancestor of crown group ecdysozoans sharing an annulated vermiform body with a terminal mouth like Acosmia, but also possessing the pharyngeal armature and circumoral structures characteristic of Cambrian cycloneuralians and lobopodians. Conclusions: Acosmia is the first taxon placed in the ecdysozoan stem group and provides a constraint to test hypotheses on the early evolution of Ecdysozoa. Our study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy (e.g. predation), may have characterised the origin and radiation of crown group ecdysozoans from Acosmia-like ancestors. | en_GB |
dc.description.sponsorship | Yunnan provincial research grant | en_GB |
dc.description.sponsorship | Natural Environment Research Council (NERC) | en_GB |
dc.identifier.citation | Vol. 20, article 156 | en_GB |
dc.identifier.doi | 10.1186/s12862-020-01720-6 | |
dc.identifier.grantnumber | 2015HA021 | en_GB |
dc.identifier.grantnumber | 2015HC029 | en_GB |
dc.identifier.grantnumber | 2019DG050 | en_GB |
dc.identifier.grantnumber | NE/L011751/1 | en_GB |
dc.identifier.uri | http://hdl.handle.net/10871/124431 | |
dc.language.iso | en | en_GB |
dc.publisher | BMC | en_GB |
dc.rights | © The Author(s) 2020. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativeco mmons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. | en_GB |
dc.subject | Ecdysozoa | en_GB |
dc.subject | Cambrian | en_GB |
dc.subject | Cycloneuralia | en_GB |
dc.subject | Panarthropoda | en_GB |
dc.subject | Palaeobiology | en_GB |
dc.subject | Phylogenetics | en_GB |
dc.subject | Phylogenetics | en_GB |
dc.title | Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2021-01-19T09:23:58Z | |
dc.description | This is the final version. Available on open access from BMC via the DOI in this record | en_GB |
dc.description | Availability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. The phylogenetic data matrix is included as a downloadable NEXUS file (Additional File 7). | en_GB |
dc.identifier.eissn | 1471-2148 | |
dc.identifier.journal | BMC Evolutionary Biology | en_GB |
dc.rights.uri | https://creativecommons.org/licenses/by/4.0/ | en_GB |
dcterms.dateAccepted | 2020-11-08 | |
exeter.funder | ::Natural Environment Research Council (NERC) | en_GB |
rioxxterms.version | VoR | en_GB |
rioxxterms.licenseref.startdate | 2020-11-23 | |
rioxxterms.type | Journal Article/Review | en_GB |
refterms.dateFCD | 2021-01-19T09:21:33Z | |
refterms.versionFCD | VoR | |
refterms.dateFOA | 2021-01-19T09:24:08Z | |
refterms.panel | A | en_GB |
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to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory
regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this
licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativeco
mmons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.