Format

Send to

Choose Destination
See comment in PubMed Commons below
Nature. 2005 Sep 1;437(7055):137-40.

The axial skeleton of the Devonian tetrapod Ichthyostega.

Author information

1
Subdepartment of Evolutionary Organismal Biology, Department of Physiology and Developmental Biology, Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden. per.ahlberg@ebc.uu.se

Abstract

Ichthyostega was the first Devonian tetrapod to be subject to a whole-body reconstruction. It remains, together with Acanthostega, one of only two Devonian tetrapods for which near-complete postcranial material is available. It is thus crucially important for our understanding of the earliest stages of tetrapod evolution and terrestrialization. Here we show a new reconstruction of Ichthyostega based on extensive re-examination of original material and augmented by recently collected specimens. Our reconstruction differs substantially from those previously published and reveals hitherto unrecognized regionalization in the vertebral column. Ichthyostega is the earliest vertebrate to show obvious adaptations for non-swimming locomotion. Uniquely among early tetrapods, the presacral vertebral column shows pronounced regionalization of neural arch morphology, suggesting that it was adapted for dorsoventral rather than lateral flexion.

PMID:
16136143
DOI:
10.1038/nature03893
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Nature Publishing Group
    Loading ...
    Support Center