In Our Region
Mesocyon had what scientists call digitigrade feet, which means that it was able to stand or walk on its toes, an adaptation that increased stride length and thus speed. When paleontologists examine these fossils, they see that the long bones of the toes are packed very close together, unlike what we see in plantigrade animals, or those that walk flat-footed.
The trend toward greatly reduced forest lands and more open grasslands which occurred during the Oligocene may have promoted the evolution of dog-like animals. We can hypothesize that dogs evolved and learned to run down their prey in environments where open grasslands became more common than thickly forested landscapes.
Dogs exploited long-distance pursuit as a strategy for capturing prey in increasingly open habitats. Cats do not do as well in open habitats as they generally stalk their prey, and need cover to hide behind.
As we observe in our own domestic dogs, fossil canids probably had an excellent sense of smell, a wide range of hearing, and good vision. They also had the advantage of being able to live on a variety of foods, and could be considered omnivores.
Wild relatives living today include three families—wolves, foxes, and coyotes. They inhabit every continent except Antarctica, so it is clear that they are adaptable to extremely variable habitats, from deserts to rain forests.
But how did dogs become domesticated? Many hypotheses exist, one being that dogs may have hung around places of early human occupation, scavenging scraps and benefiting from human hunting. Perhaps they were used as a food source themselves. Eventually their presence either became beneficial to humans in terms of their superior hearing and sense of smell, or some other factor came into play.
Where did the first domesticated dogs occur? Some biologists have suggested that the dingoes of Australian aborigines may have been the first domesticated dogs on Earth, although other scientists hypothesize that domestication originated in Asia.
Genetic evidence indicates that domestic dogs came to the New World along with humans, migrating over the Bering Strait some 12,000 years ago. We still have much to learn about the process of the domestication of dogs.
Text: Margaret Dykens and Lynett Gillette