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Ray-finned fish phylogeny resolved



From: Ben Creisler
bcreisler@gmail.com


OK--not dino and not strictly Mesozoic. However, the evolution of
teleosts affected the evolution of marine reptiles and maybe of some
theropods, including birds.


Thomas J. Near, Ron I. Eytan, Alex Dornburg, Kristen L. Kuhn, Jon A.
Moore, Matthew P. Davis, Peter C. Wainwright, Matt Friedman, and W.
Leo Smith (2012)
Resolution of ray-finned fish phylogeny and timing of diversification.
Proceedings of the National Academy of Sciences (advance online publication)
doi: 10.1073/pnas.1206625109
http://www.pnas.org/content/early/2012/08/03/1206625109.abstract?sid=9f83fe96-5659-4666-b48e-d918413eef5d


Ray-finned fishes make up half of all living vertebrate species.
Nearly all ray-finned fishes are teleosts, which include most
commercially important fish species, several model organisms for
genomics and developmental biology, and the dominant component of
marine and freshwater vertebrate faunas. Despite the economic and
scientific importance of ray-finned fishes, the lack of a single
comprehensive phylogeny with corresponding divergence-time estimates
has limited our understanding of the evolution and diversification of
this radiation. Our analyses, which use multiple nuclear gene
sequences in conjunction with 36 fossil age constraints, result in a
well-supported phylogeny of all major ray-finned fish lineages and
molecular age estimates that are generally consistent with the fossil
record. This phylogeny informs three long-standing problems:
specifically identifying elopomorphs (eels and tarpons) as the sister
lineage of all other teleosts, providing a unique hypothesis on the
radiation of early euteleosts, and offering a promising strategy for
resolution of the “bush at the top of the tree” that includes
percomorphs and other spiny-finned teleosts. Contrasting our
divergence time estimates with studies using a single nuclear gene or
whole mitochondrial genomes, we find that the former underestimates
ages of the oldest ray-finned fish divergences, but the latter
dramatically overestimates ages for derived teleost lineages. Our
time-calibrated phylogeny reveals that much of the diversification
leading to extant groups of teleosts occurred between the late
Mesozoic and early Cenozoic, identifying this period as the “Second
Age of Fishes.”