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Testing hypotheses of the evolution of encephalization in the Canidae (Carnivora, Mammalia)

Published online by Cambridge University Press:  08 April 2016

John A. Finarelli*
Affiliation:
Committee on Evolutionary Biology, University of Chicago, 1025 East Fifty-seventh Street, Chicago, Illinois 60637

Abstract

Evolutionary trends observed over large clades have the potential to mask underlying trends that occur within their constituent subclades. A recent study of encephalization in the Caniformia (Carnivora, Mammalia) found evidence for an abrupt increase in median log-encephalization quotients (logEQs), indicating higher brain volume relative to body mass, at the end-Miocene, but gradual increase in the variance of logEQs. In this study, new endocranial volume estimates for fossil taxa in the well-sampled caniform subclade Canidae are reported. Using the encephalization data for the Canidae, hypotheses of evolution in encephalization allometries were tested with respect to canid phylogeny. The Akaike Information Criterion and likelihood ratios recovered support for a preferred hypothesis of the evolution of canid encephalization, which proposed two distinct allometric relationships: (1) a plesiomorphic grade of encephalization in the subfamilies Hesperocyoninae and Borophaginae and the paraphyletic canine genus Leptocyon, and (2) an apomorphic grade in the crown radiation of Caninae. This defines a shift in to higher encephalization, but without an associated change in the variance around the allometry. Increased canid encephalization coincides with a reorganization of the brain and the observed trend may reflect the evolution of complex social behavior in this clade.

Type
Articles
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Akaike, H. 1973. Information theory as an extension of the maximum likelihood principle. Pp. 267281in Petrov, B. N. and Csaki, F., eds. Second International Symposium on Information Theory. Akademiai Kiado, Budapest.Google Scholar
Alroy, J. 2002. North American fossil mammal systematics database. Available online athttp://www.nceas.ucsb.edu/~alroy/nafmsd.html.Google Scholar
Andersson, K. 2005. Were there pack-hunting canids in the Tertiary, and how can we know? Paleobiology 31:5672.Google Scholar
Bardeleben, C., Moore, R. L., and Wayne, R. K. 2005. A molecular phylogeny of the Canidae based on six nuclear loci. Molecular Phylogenetics and Evolution 37:815831.Google Scholar
Burnham, K. P., and Anderson, D. R. 2002. Model selection and multimodel inference: a practical information-theoretic approach. Springer, New York.Google Scholar
Carbone, C., Mace, G. M., Roberts, S. C., and Macdonald, D. W. 1999. Energetic constraints on the diet of terrestrial carnivores. Nature 402:286288.Google Scholar
Carbone, C., Teacher, A., and Rowcliffe, J. M. 2007. The cost of carnivory. PLoS Biology 5(2):03630368.Google Scholar
Cerling, T. E., Harris, J. M., MacFadden, B. J., Leakey, M. G., Quade, J., Eisenmann, V., and Ehleringer, J. R. 1997. Global vegetation change through the Miocene/Pliocene boundary. Nature 389:153158.Google Scholar
Edwards, A. W. F. 1992. Likelihood, expandeded. Johns Hopkins University Press, Baltimore.Google Scholar
Finarelli, J. A. 2006. Estimation of endocranial volume through the use of external skull measures in the Carnivora (Mammalia). Journal of Mammalogy 87:10271036.Google Scholar
Finarelli, J. A. 2007. Mechanisms behind active trends in body size evolution in the Canidae (Carnivora: Mammalia). American Naturalist (in press).Google Scholar
Finarelli, J. A., and Flynn, J. J. 2006. Ancestral state reconstruction of body size in the Caniformia (Carnivora, Mammalia): the effects of incorporating data from the fossil record. Systematic Biology 55:301313.Google Scholar
Finarelli, J. A., and Flynn, J. J. 2007. The evolution of encephalization in caniform carnivorans. Evolution 61:17581772.Google Scholar
Gittleman, J. L., and Harvey, P. H. 1982. Carnivore home-range size, metabolic needs and ecology. Behavioral Ecology and Sociobiology 10:5763.Google Scholar
Hurvich, C. M., and Tsai, C.-L. 1989. Regression and time series model selection in small samples. Biometrika 76:297307.Google Scholar
Jerison, H. 1970. Brain evolution: new light on old principles. Science 170:12241225.Google Scholar
Jerison, H. 1991. Brain size and the evolution of mind. American Museum of Natural History, New York.Google Scholar
Lyras, G. A., and Van der Geer, A. A. E. 2003. External brain anatomy in relation to the phylogeny of Caninae (Carnivora: Canidae). Zoological Journal of the Linnean Society 138:505522.Google Scholar
Marino, L., McShea, D. W., and Uhen, M. D. 2004. Origin and evolution of large brains in toothed whales. Anatomical Record, Part A, Discoveries in Molecular Cellular and Evolutionary Biology 281:12471255.Google Scholar
Martin, R. D. 1981. Relative brain size and basal metabolic-rate in terrestrial vertebrates. Nature 2937:5760.Google Scholar
McShea, D. W. 1994. Mechanisms of large-scale evolutionary trends. Evolution 48:17471763.Google Scholar
NOW-database. 2003. Available athttp://www.helsinki.fi/science/now/index.html, Version 17, July, 2003.Google Scholar
Oakley, T. H., and Cunningham, C. W. 2000. Independent contrasts succeed where ancestor reconstruction fails in a known bacteriophage phylogeny. Evolution 54:397405.Google Scholar
Pagel, M. D., and Harvey, P. H. 1988. How mammals produce large-brained offspring. Evolution 42:948957.Google Scholar
Polly, P. D. 2001. Paleontology and the comparative method: ancestral node reconstructions versus observed node values. American Naturalist 157:596609.Google Scholar
Polly, P. D., Wesley-Hunt, G. D., Heinrich, R. E., Davis, G., and Houde, P. 2006. Earliest known carnivoran auditory bulla and support for a recent origin of crown-group Carnivora (Eutheria, Mammalia). Palaeontology 49:10191027.Google Scholar
Radinsky, L. 1969. Outlines of canid and felid brain evolution. Annals of the New York Academy of Sciences 167:277288.Google Scholar
Radinsky, L. 1973. Evolution of the canid brain. Brain, Behavior and Evolution 7:169202.Google Scholar
Radinsky, L. 1977. Brains of early carnivores. Paleobiology 3:333349.CrossRefGoogle Scholar
Radinsky, L. 1978. Evolution of brain size in carnivores and ungulates. American Naturalist 112:815831.Google Scholar
Royall, R. M. 1997. Statistical evidence: a likelihood paradigm. Chapman and Hall, New York.Google Scholar
Schluter, D., Price, T., Mooers, A. O., and Ludwig, D. 1997. Likelihood of ancestor states in adaptive radiation. Evolution 51:16991711.Google Scholar
Sokal, R. R., and Rohlf, F. J. 1995. Biometry: the principles and practice of statistics in biological research, 3d ed.W. H. Freeman, New York.Google Scholar
Tedford, R. H., Taylor, B. E., and Wang, X. M. 1995. Phylogeny of the Caninae (Carnivora: Canidae): the living taxa. American Museum Novitates 3146:137.Google Scholar
Van Valkenburgh, B. 1991. Iterative evolution of hypercarnivory in canids (Mammalia, Carnivora): evolutionary interactions among sympatric predators. Paleobiology 17:340362.Google Scholar
Van Valkenburgh, B., Sacco, T., and Wang, X. M. 2003. Pack hunting in Miocene borophagine dogs: evidence from craniodental morphology and body size. Bulletin of the American Museum of Natural History 279:147162.Google Scholar
Van Valkenburgh, B., Wang, X. M., and Damuth, J. 2004. Cope's Rule, hypercarnivory, and extinction in North American canids. Science 306:101104.Google Scholar
Wagner, P. J. 1996. Contrasting the underlying patterns of active trends in morphologic evolution. Evolution 50:9901007.Google Scholar
Wagner, P. J. 2000a. Likelihood tests of hypothesized durations: determining and accommodating biasing factors. Paleobiology 26:431449.Google Scholar
Wagner, P. J. 2000b. Phylogenetic analyses and the fossil record: tests and inferences, hypotheses and models. In Erwin, D. H. and Wing, S. L., eds. Deep time: Paleobiology's perspective. Paleobiology 26(Suppl. to No. 4):341371.Google Scholar
Wagner, P. J. 2001. Rate heterogeneity in shell character evolution among lophospiroid gastropods. Paleobiology 27:290310.2.0.CO;2>CrossRefGoogle Scholar
Wagner, P. J., Kosnik, M. A., and Lidgard, S. 2006. Abundance distributions imply elevated complexity of post-Paleozoic marine ecosystems. Science 314:12891292.Google Scholar
Wang, X. M. 1994. Phylogenetic systematics of the Hesperocyoninae (Carnivora: Canidae). Bulletin of the American Museum of Natural History 221:1207.Google Scholar
Wang, X. M., Tedford, R. H., and Taylor, B. E. 1999. Phylogenetic systematics of the Borophaginae (Carnivora: Canidae). Bulletin of the American Museum of Natural History 243:1391.Google Scholar
Wang, X. M., Tedford, R. H., Van Valkenburgh, B., and Wayne, R. K. 2004. Chapter 2. Ancestry: evolutionary history, molecular systematics, and evolutionary ecology of Canidae. Pp. 3954in Macdonald, D. W. and Sillero-Zubiri, C., eds. The biology and conservation of wild canids. Oxford University Press, Oxford.Google Scholar
Wayne, R. K., Geffen, E., Girman, D. J., Koepfli, K. P., Lau, L. M., and Marshall, C. R. 1997. Molecular systematics of the Canidae. Systematic Biology 46:622653.Google Scholar
Wesley-Hunt, G. D., and Flynn, J. J. 2005. Phylogeny of the Carnivora: basal relationships among the carnivoramorphans, and assessment of the position of “Miacoidea” relative to crown-clade Carnivora. Journal of Systematic Palaeontology 3:128.Google Scholar