What makes a wolf

Abstract

The zoological order Carnivora includes the canids. When discussing its members the term carnivoran is preferable to carnivore because it excludes unrelated predators. Modern canids appeared about 10 million years before the present (years BP) and diverged into two branches, the dogs and the foxes. Depending on how you divide them, living canids number about 35 species. They have 78 chromosomes , and all are known to admix . The golden jackal ( Canis aureus ) and gray wolf ( Canis lupus ) have been considered the domestic dog's possible ancestors, and although all evidence points to the gray wolf, some raise other possibilities, such as an extinct and unknown wolf-like canid. Two of these are the dingo and a hypothetical and now extinct wild dog similar to the dingo. The next closest relatives of gray wolves and domestic dogs are the coyote and Ethiopian wolf ( Canis simensis ), less accurately called the Simien jackal. As later chapters should help clarify, implications of these relationships reach out from the past, affecting the behavior and social lives of all members of the genus Canis , including the domestic dogs we keep as pets. Wolves in the beginning The family Canidae ( Canis means dog in Latin) evolved in North America, first appearing in the late Miocene 6 million years BP. When North America and Asia formed a high-latitude connection in the late Cenozoic (3 million years BP) some canids migrated across, where they continued to evolve, and one returned later as the gray wolf. The record infers that North American wolves and the coyote separated about 1–2 million years BP, although genetic findings point to the gray wolf's origin being only 250 000 years BP. According to a slightly different hypothesis, the gray wolf might have evolved in Asia and migrated to North America about 300 000 years BP across the Bering land bridge when sea levels were lower than today.