FLIPPERS AND PINNIPED PHYLOGENY: HAS THE PROBLEM OF CONVERGENCE BEEN OVERRATED?
Article first published online: 26 AUG 2006
Marine Mammal Science
Volume 5, Issue 4, pages 343–360, October 1989
How to Cite
Wyss, A. R. (1989), FLIPPERS AND PINNIPED PHYLOGENY: HAS THE PROBLEM OF CONVERGENCE BEEN OVERRATED?. Marine Mammal Science, 5: 343–360. doi: 10.1111/j.1748-7692.1989.tb00347.x
- Issue published online: 26 AUG 2006
- Article first published online: 26 AUG 2006
- Received: April 17, 1989 Accepted: May 29, 1989
- phylogenetic systematics;
The phylogenetic relationships of the major groups of pinnipeds are of longstanding controversy. According to prevailing paleontological opinion, pinnipeds comprise two distinct lineages of independent terrestrial carnivoran origin, A logical correlate of this view is that an enormous degree of convergence accounts for the striking resemblances of these groups.
It has been generally supposed that derived similarities common to pinnipeds are independently acquired adaptations to a highly constraining environment. This has not been adequately substantiated. Moreover, considerable evidence favors a contrary conclusion. Acceptance of convergence necessarily rests on demonstration that taxa possessing characters suspected to be convergent are in fact not mutal nearest allies. In the absence of such phylogenetic information, shared derived characters are indicative of common ancestry irrespective of whether they are deemed “functionally important.” Given meager support for the proposition that pinnipeds are related to different terrestrial lineages, it is currently more judicious to regard the group's origin as monophyletic. In addition to the presumed prevalence of convergence, biogeography, the high degree of morphological divergence of phocids, and the aberrant nature of phocines have improperly contributed to acceptance of independent pinniped origins.