Cope's Rule, Hypercarnivory, and Extinction in North American Canids

Over the past 50 million years, successive clades of large carnivorous mammals diversified and then declined to extinction. In most instances, the cause of the decline remains a puzzle. Here we argue that energetic constraints and pervasive selection for larger size (Cope's rule) in carnivores lead to dietary specialization (hypercarnivory) and increased vulnerability to extinction. In two major clades of extinct North American canids, the evolution of large size was associated with a dietary shift to hypercarnivory and a decline in species durations. Thus, selection for attributes that promoted individual success resulted in progressive evolutionary failure of their clades.

[1]  J. Damuth.  Interspecific allometry of population density in mammals and other animals: the independence of body mass and population energy‐use , 1987 .

[2]  J. Damuth.  Analysis of the preservation of community structure in assemblages of fossil mammals , 1982, Paleobiology.

[3]  J. Damuth,et al.  Population density and body size in mammals , 1981, Nature.

[4]  B. Valkenburgh.  Iterative evolution of hypercarnivory in canids (Mammalia: Carnivora): evolutionary interactions among sympatric predators , 1991 .

[5]  S. Gould.  Both Neonate and Elder: The First Fossil of 1557 , 2002, Paleobiology.

[6]  Catherine Badgley,et al.  Faunal and environmental change in the late Miocene Siwaliks of northern Pakistan , 2002, Paleobiology.

[7]  Susan C. Roberts,et al.  Energetic constraints on the diet of terrestrial carnivores , 1999, Nature.

[8]  T. Caro,et al.  Interspecific Killing among Mammalian Carnivores , 1999, The American Naturalist.

[9]  D. Jablonski.  Body-size evolution in Cretaceous molluscs and the status of Cope's rule , 1997, Nature.

[10]  J. L. Gittleman,et al.  Predicting extinction risk in declining species , 2000, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[11]  J. Alroy.  Cope's rule and the dynamics of body mass evolution in North American fossil mammals. , 1998, Science.

[12]  J. Damuth.  Cope's rule, the island rule and the scaling of mammalian population density , 1993, Nature.

[13]  B. Valkenburgh.  MAJOR PATTERNS IN THE HISTORY OF CARNIVOROUS MAMMALS , 1999 .

[14]  D. Western,et al.  New perspectives in vertebrate paleoecology from a recent bone assemblage , 1979, Paleobiology.

[15]  S. Stanley,et al.  Macroevolution: Pattern and Process , 1980 .