uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Origin and evolution of the panarthropod head: A palaeobiological and developmental perspective
Univ Cambridge.
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.ORCID iD: 0000-0001-9007-4369
2017 (English)In: Arthropod structure & development, ISSN 1467-8039, E-ISSN 1873-5495, Vol. 46, no 3, 354-379 p.Article, review/survey (Refereed) Published
Abstract [en]

The panarthropod head represents a complex body region that has evolved through the integration and functional specialization of the anterior appendage-bearing segments. Advances in the developmental biology of diverse extant organisms have led to a substantial clarity regarding the relationships of segmental homology between Onychophora (velvet worms), Tardigrada (water bears), and Euarthropoda (e.g. arachnids, myriapods, crustaceans, hexapods). The improved understanding of the segmental organization in panarthropods offers a novel perspective for interpreting the ubiquitous Cambrian fossil record of these successful animals. A combined palaeobiological and developmental approach to the study of the panarthropod head through deep time leads us to propose a consensus hypothesis for the intricate evolutionary history of this important tagma. The contribution of exceptionally preserved brains in Cambrian fossils together with the recognition of segmentally informative morphological characters illuminate the polarity for major anatomical features. The euarthropod stem-lineage provides a detailed view of the step-wise acquisition of critical characters, including the origin of a multiappendicular head formed by the fusion of several segments, and the transformation of the ancestral protocerebral limb pair into the labrum, following the postero-ventral migration of the mouth opening. Stem-group onychophorans demonstrate an independent ventral migration of the mouth and development of a multisegmented head, as well as the differentiation of the deutocerebral limbs as expressed in extant representatives. The anterior organization of crown-group Tardigrada retains several ancestral features, such as an anterior-facing mouth and one-segmented head. The proposed model aims to clarify contentious issues on the evolution of the panarthropod head, and lays the foundation from which to further address this complex subject in the future.

Place, publisher, year, edition, pages
ELSEVIER SCI LTD , 2017. Vol. 46, no 3, 354-379 p.
Keyword [en]
(Eu)arthropod head problem, Cambrian, Lobopodians, Stem-group Euarthropoda, Onychophora, Tardigrada
National Category
Earth and Related Environmental Sciences
Identifiers
URN: urn:nbn:se:uu:diva-332753DOI: 10.1016/j.asd.2016.10.011ISI: 000402942400004PubMedID: 27989966OAI: oai:DiVA.org:uu-332753DiVA: diva2:1155029
Funder
Swedish Research Council, 621-2011-4703
Available from: 2017-11-06 Created: 2017-11-06 Last updated: 2017-11-06Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Janssen, RalfBudd, Graham E.
By organisation
Palaeobiology
In the same journal
Arthropod structure & development
Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 19 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf