Vulpes vulpes, the red fox, ranges throughout the northern hemisphere from North America (excluding some areas of the central plains and the Arctic) to north Africa and Eurasia (excluding the tundra). The species V. vulpes originated in Eurasia, appearing in the fossil record about 1.5 million years ago; it reached North America via Beringia about 130,000 years ago. The European subspecies was introduced into the eastern United States in the 1600’s, where it interbred with the local subspecies. Vulpes vulpes was present in Texas until the end of the Pleistocene, only to be "reintroduced" into the state in the late 1800’s. The red fox was also introduced into Australia in Victoria in the 1860’s, and by the 1910’s it was found in Western Australia.

Vulpes vulpes is most closely related to the kit or swift fox (V. velox) of North America, the Arctic fox (Alopex lagopus), and the foxes of Africa (V. cana, V. pallida, V. ruepelli, and V. zerda) and Eurasia (V. bengalensis, V. corsac, and V. ferrilata). Allozyme divergence and paleontological data indicate that the common ancestor of the Vulpes group originated in North America and diverged from other canids between 9 and 11 million years before present.

The skull of Vulpes vulpes is easily differentiated from that of Canis (e.g., the coyote, C. latrans, and the gray wolf, C. lupus). Vulpes vulpes has a relatively long muzzle with less convex (i.e., flattened) frontal bones, and the nasal bones are short, terminating in front of the maxillary-frontal suture. Vulpes lacks frontal sinuses, which is a primitive feature, and the canine teeth are relatively longer and more slender than those of Canis. While V. vulpes is not as sexually dimorphic as Canis, the males are generally larger than females in average body size. Morphometric analyses of cranial data from European populations of V. vulpes indicate that the skulls of male red foxes are more elongate and have a relatively narrower postorbital constriction than those of female red foxes.

This specimen, a male of the subspecies alascensis, was collected in Barrow, Alaska. It was made available to The University of Texas High-Resolution X-ray CT Facility for scanning courtesy of Drs. Blaire Van Valkenburgh and Jessica Theodor, Department of Organismic Biology, Ecology, and Evolution, University of California, Los Angeles. Funding for scanning was provided by Dr. Van Valkenburgh and by a National Science Foundation Digital Libraries Initiative grant to Dr. Timothy Rowe of The University of Texas at Austin. This red fox is one of several canid carnivorans included in ongoing research of respiratory turbinates by Drs. Van Valkenburgh and Theodor.

The specimen was scanned by Matthew Colbert on 13 October 2000 along the coronal axis for a total of 537 slices, each slice 0.279 mm thick with an interslice spacing of 0.279 mm. The dataset displayed was reduced for optimal Web delivery from the original, much higher resolution CT data.

Literature

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Anderson, E. 1984. Review of the small carnivores of North America during the last 3.5 million years. Special Publication of the Carnegie Museum of Natural History 8:257-266.

Geffen, E., A. Mercure, D. J. Girman, D. W. MacDonald, and R. K. Wayne. 1992. Phylogenetic relationships of the fox-like canids: mitochondrial DNA restriction fragment, site and cytochrome beta sequence analyses. Journal of Zoology (London) 228:27-39.

Ginsberg, J. R., and D. W. Macdonald. 1990. Foxes, wolves, jackals, and dogs: an action plan for the conservation of canids. IUCN, Gland, Switzerland, 116 pp.

Huxley, T. H. 1880. On the cranial and dental characters of the Canidae. Proceedings of the Zoological Society of London 16:238-288.

Jaslow, C. R. 1987. Morphology and digestive efficiency of red foxes Vulpes vulpes and gray foxes Urocyon cinereoargenteus in relation to diet. Canadian Journal of Zoology 65:72-79.

Kurtén, B., and E. Anderson. 1980. Pleistocene Mammals of North America. Columbia University Press, New York. 442 pp.

Lariviere, S., and M. Pasitschniak-Arts. 1996. Vulpes vulpes. Mammalian Species 537:1-11.

Lloyd, H. G. 1981. The red fox. B. T. Batsford, Ltd., London.

Lynch, J. M. 1996. Sexual dimorphism in cranial size and shape among red foxes, Vulpes vulpes, from North-East Ireland. Proceedings of the Royal Irish Academy, Series B, Biology and Environment 96:21-26.

Martinkova, A., and M. Janiga. 1999. Quantitative comparisons of cranial shape and size in adults of Felis sylvestris, Vulpes vulpes, Mustela putorius, and Mustela nivalis from the West Carpathians (Slovakia). Oecologia Montana 8:32-37.

Tedford, R. H., B. E. Taylor, and X. Wang. 1995. Phylogeny of the Caninae (Carnivora: Canidae): the living taxa. American Museum Novitates 3146:1-37.

Tedford, R. H., X. Wang, and B. E. Taylor. 2001. History of the Caninae (Canidae). Journal of Vertebrate Paleontology 21:107A.

Van Valkenburgh, B., J. Theodor, A. Friscia, and T. Rowe. 2001. Respiratory turbinates of carnivorans revealed by CT scans: a quantitative comparison. Journal of Vertebrate Paleontology 21:110A.

Wayne, R. K., E. Geffen, D. J. Girman, K. P. Koepfli, L. M. Lau, and C. R. Marshall. 1997. Molecular systematics of the Canidae. Systematic Biology 46:622-653.

Wilson, G., N. Dexter, P. O'Brien, and M. Bomford. 1992. Pest animals in Australia. A survey of introduced wild mammals. Bureau of Rural Resources and Kangaroo Press Pty Ltd., Canberra, Australia.

Vulpes vulpes species account provided by the IUCN Canid Specialist Group

Vulpes vulpes on The Mammals of Texas Online Edition

The brain of Vulpes vulpes (Comparative Mammalian Brain Collections website)

Vulpes vulpes on The Animal Diversity Web (The University of Michigan Museum of Zoology)

Wild Facts on the red fox from the BBC Online website (includes audio)

Other fox links from Vulpes World

Vulpes vulpes on CalPhotos.