Palaeontological Approaches to the Arthropod Head Problem
(English)Conference paper (Other academic)
The arthropod head problem remains a daunting problem, and stillremains some distance away from solution: several distinct palaeontologicalcontributions have been made in the last few years alone. Suchwork needs to be integrated into molecular and developmentalapproaches to make the most effective assault on the problem. The statusof the labrum, its cross-group homology, and its appendiculate ornonappendiculate nature, remains particularly controversial. Nevertheless,some progress has been made by the erection of various stemgroupsto arthropod taxa, and these allow the partial tracing of the evolutionof the arthropod head. Recent work suggests that the upper stemgroupeuarthropods are all characterized by similar head structures, theorigins of which in turn may be traced back even deeper into the anomalocarididsand their relatives. Nevertheless, several potentially key taxa,such as Sanctacaris, remain hard to understand, whilst others, notablySidneyia, are typically ignored in analyses of the problem. Such taxamay have bearings on the origin of the upper euarthropod stem groupand chelicerate stem group, respectively. Despite the apparent argumentsraging about the fossil arthropod systematics, a distinct convergence ofopinion over many clades has taken place over the last few years: puttingthem together to form a consensus of palaeontological input intoresolving the arthropod head problem, however, remains some way off.
Earth and Related Environmental Sciences
IdentifiersURN: urn:nbn:se:uu:diva-88295OAI: oai:DiVA.org:uu-88295DiVA: diva2:145403
1st International Congress of Invertebrate Morphology
Abrstract published in Journal of Morphology, ISSN 0362-2525, 2008, 269 (12), page 1468 2009-01-282009-01-282010-01-27Bibliographically approved