Udell, Dorey, and Wynne (2011) demonstrated that both domesticated and nondomesticated canids-specifically, gray wolves-have the capacity to succeed on perspective-taking tasks, suggesting that dogs' ability to respond to the human attentional state is not a by-product of domestication alone. Furthermore, not all dogs were successful on the task. Instead, the occluder type used was a strong pre...

BACKGROUND Understanding how kill rates vary among seasons is required to understand predation by vertebrate species living in temperate climates. Unfortunately, kill rates are only rarely estimated during summer. METHODOLOGY/PRINCIPAL FINDINGS For several wolf packs in Yellowstone National Park, we used pairs of collared wolves living in the same pack and the double-count method to estimate ...

In Late Pleistocene Italy, spotted hyenas competed in certain niche dimensions with wolves and in other dimensions with Paleolithic humans. Spotted hyenas of the Italian peninsula consumed essentially the same ungulate species as Paleolithic humans did, and both of these predators depended heavily on bone marrow. Wolves tended to consume more hillside-adapted ungulates in the same area and peri...

Wolves (Canis lupus) have expanded their distribution into areas of the midwest United States that have not had wolves for several decades. With recolonization of wolves into agricultural areas, there is increasing concern of wolf–livestock conflicts. To assess the risk wolves may pose to livestock, we initiated a 3-year study investigating the activity patterns, movements, habitat use, visitat...

Genetic data suggest that red wolves (Canis rufus) resulted from a hybridization between coyotes (C. latrans) and grey wolves (C. lupus). The data of the hybridization, however, is uncertain. According to one hypothesis, the two species came into contact as coyotes increased their geographical range in conjunction with the advance of European settlers and as grey wolves were extirpated from the...

Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ ...

There is considerable interest in the genetics of wolves (Canis lupus) because of their close relationship to domestic dogs (C. familiaris) and the need for informed conservation and management. This includes wolf populations in Southeast Alaska for which we determined genotypes of 305 wolves at 173662 single nucleotide polymorphism (SNP) loci. After removal of invariant and linked SNP, 123801 ...

Living coyotes modify their behavior in the presence of larger carnivores, such as wolves. However, little is known about the effects of competitor presence or absence on morphological change in coyotes or wolves over long periods of time. We examined the evolution of coyotes and wolves through time from the late Pleistocene, during which many large carnivorous species coexisted as predators an...

Mercury (Hg) bioaccumulates in the tissues of organisms and biomagnifies within food-webs. Gray wolves (Canis lupus) in Alaska primarily acquire Hg through diet; therefore, comparing the extent of Hg exposure in wolves, in conjunction with stable isotopes, from interior and coastal regions of Alaska offers important insight into their feeding ecology. Liver, kidney, and skeletal muscle samples ...