Early vertebrate evolution

• DOI: 10.1111/pala.12125
• Publication Date: 2014-08-15T15:50:20Z
• Authors: Philip C. J. Dono...; Joseph N. Keating
• Keywords: Living fossil; Macroevolution; Monophyly; Deuterostome; Chordate; Character evolution; Fossil Record; Cladogenesis; Tetrapod (structure); Evolution of mammals

Abstract Debate over the origin and evolution of vertebrates has occupied biologists palaeontologists alike for centuries. This debate been refined by molecular phylogenetics, which resolved place among their invertebrate chordate relatives, that chordates deuterostome relatives. The is characterized wide‐ranging genomic, embryologic phenotypic evolutionary change. Analyses based on living lineages suggest dramatic shifts in tempo change at gnathostomes, coincident with whole‐genome duplication events. However, enriched perspective provided fossil record demonstrates these apparent bursts anatomical taxic richness are an artefact extinction phylogenetic intermediates whose remains evidence gradual assembly crown gnathostome characters particular. A more understanding timing, mode early vertebrate rests with: (1) better genome assemblies cyclostomes; (2) a characteristics key groups, especially anaspids, thelodonts, galeaspids pituriaspids; (3) tests monophyly traditional groups; (4) application divergence time methods integrate not just data from species, but also morphological extinct species. resulting framework will provide rigorous rates character diversification, hypotheses long‐term trends ecological themselves suffer lack quantitative functional tests. silent nature transition jawless to jawed have dominated communities since middle P alaeozoic. Elucidation this most formative episodes likely overhaul systematics we propose, perhaps fundamentally grades await discovery.