The humerus of Panderichthys in three dimensions and its significance in the context of the fish-tetrapod transition
2009 (English)In: Acta Zoologica (Stockholm), ISSN 0001-7272, E-ISSN 1463-6395, Vol. 90, no suppl 1, 297-305 p.Article in journal (Refereed) Published
The humerus of Panderichthyshas been considered to represent a transitionalform between that of tetrapodomorph fish such asEusthenopteronandtetrapods such asAcanthostega. The previous description was based onflattened material and was analysed in the context of the few fossils known atthe time. Since then, several new forms have been described such asGogonasus,Tiktaalikand an isolated humerus from the Catskill Formation. The humeralmorphology ofPanderichthys rhombolepisand its interpretation in this newcontext are therefore reassessed with the help of a three-dimensional modelproduced with themimicssoftware based on a computed tomography scan ofan unflattened specimen as well as comparisons with the originally describedmaterial. The humerus ofPanderichthysdisplays a combination of primitive,derived, intermediate and unique characteristics. It is very similar to themorphology ofTiktaalikbut when it differs from it, it is most often morederived despite the more basal phylogenetic position thatPanderichthysoccupies. What emerges from this study is a much more gradual transformationof the humerus morphology from fish to tetrapods and the ability to distinguishautapomorphies more easily. The picture is more complex than previouslybelieved, with many morphological specializations probably reflecting thebreadth of ecological specializations already present at the time.
Place, publisher, year, edition, pages
2009. Vol. 90, no suppl 1, 297-305 p.
fish-tetrapod transition, sarcopterygian, humeri, pectoral musculature
Research subject Pathology
IdentifiersURN: urn:nbn:se:uu:diva-98908DOI: 10.1111/j.1463-6395.2008.00389.xISI: 000266242000025OAI: oai:DiVA.org:uu-98908DiVA: diva2:201521