title: A phylogenetic blueprint for a modern whale.
abstract: The emergence of Cetacea in the Paleogene represents one of the most profound macroevolutionary transitions within Mammalia. The move from a terrestrial habitat to a committed aquatic lifestyle engendered wholesale changes in anatomy, physiology, and behavior. The results of this remarkable transformation are extant whales that include the largest, biggest brained, fastest swimming, loudest, deepest diving mammals, some of which can detect prey with a sophisticated echolocation system (Odontoceti - toothed whales), and others that batch feed using racks of baleen (Mysticeti - baleen whales). A broad-scale reconstruction of the evolutionary remodeling that culminated in extant cetaceans has not yet been based on integration of genomic and paleontological information. Here, we first place Cetacea relative to extant mammalian diversity, and assess the distribution of support among molecular datasets for relationships within Artiodactyla (even-toed ungulates, including Cetacea). We then merge trees derived from three large concatenations of molecular and fossil data to yield a composite hypothesis that encompasses many critical events in the evolutionary history of Cetacea. By combining diverse evidence, we infer a phylogenetic blueprint that outlines the stepwise evolutionary development of modern whales. This hypothesis represents a starting point for more detailed, comprehensive phylogenetic reconstructions in the future, and also highlights the synergistic interaction between modern (genomic) and traditional (morphological+paleontological) approaches that ultimately must be exploited to provide a rich understanding of evolutionary history across the entire tree of Life.
authors.affiliation: Department of Biology, University of California, Riverside, CA 92521, USA. john.gatesy@ucr.edu
authors.forename: John
authors.initials: J
authors.lastname: Gatesy
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Geisler
authors.forename: Joseph
authors.initials: J
authors.lastname: Chang
authors.forename: Carl
authors.initials: C
authors.lastname: Buell
authors.forename: Annalisa
authors.initials: A
authors.lastname: Berta
authors.forename: Robert W
authors.initials: RW
authors.lastname: Meredith
authors.forename: Mark S
authors.initials: MS
authors.lastname: Springer
authors.forename: Michael R
authors.initials: MR
authors.lastname: McGowen
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005580:Fossils; D010163:Paleontology; D010802:Phylogeny; D014907:Whales / Q000145:classification* / Q000235:genetics