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Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
Vertebrate evolution. Evolutionary innovation and ecology in marine tetrapods from the Triassic to the Anthropocene
Neil P Kelley1, Nicholas D Pyenson2
1Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA. Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN 37240, USA. kelleynp@si.edu.
Abstract:
Many top consumers in today's oceans are marine tetrapods, a collection of lineages independently derived from terrestrial ancestors. The fossil record illuminates their transitions from land to sea, yet these initial invasions account for a small proportion of their evolutionary history. We review the history of marine invasions that drove major changes in anatomy, physiology, and ecology over more than 250 million years. Many innovations evolved convergently in multiple clades, whereas others are unique to individual lineages. The evolutionary arcs of these ecologically important clades are framed against the backdrop of mass extinctions and regime shifts in ocean ecosystems. Past and present human disruptions to marine tetrapods, with cascading impacts on marine ecosystems, underscore the need to link macroecology with evolutionary change.
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