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The evolution history of the wolf is not totally clear, but many biologists such as the esteemed L. David Mech believed that the wolves and their chief prey - the large hoofed herbivores - probably evolved from a common ancestor: a rodent-like, insect eating creature. If we then move forward to say, 100 million years ago, a group of primitive meat eaters evolved from those rodents, made their appearance from which descended all major carnivores as we know them today - canids, felines etc.
However, the key ancestor of the wolf may have been a member of a family called the Miacoidea or the Miacids, which lived during a prehistoric age called the Eocene period (54-38 million years ago). From their fossilized bones and teeth, experts believe that these early ancestors were tree-dwellers, with spreading paws and the distinctive carviniasial teeth. Two examples of these animals include Hesperocyon in North America and Cynodictis in Europe. With long bodies and short limbs, they resembled the modern civet (a member of the cat family) in shape.
The Evolutionary Tree of the Wolf
Adapted From: The Wolf Almanac by Busch, Robert H., pg.2
Relatively late in the evolutionary history of miacids, came the appearance of the first canid or the true proto-wolf. Some authorities believe these canids originated in North America and then spread to Asian and South America, whole others ascribe an Asian origin to the group. Still others believe that the dog family originated in North America, migrated to Asia, and then returned.
Paths of Evolution
Art Source From: Wolf to Woof by Anton, Maurico / National Geographic, January 2002, pg.8-9
Wolf ancestors began to develop in the Paleocene, about sixty million years ago. By the Miocene, some twenty million years ago, canines and felines had branched into two separate families. The first moving out onto open country, the bone structure of their feet gradually changing, growing longer limbs for speed to make it easier for them to chase down their prey, and the latter staying behind to pursue a tree-based hunting style, developing retractable claws to facilitate it.
In one ancestor of the wolf, a genuinely doglike creature known as the Tomarctus, the fifth toe on its hind leg became vestigial, and is evidenced today by the dewclaw on both wolves and domestic dogs.
Research of Robert Wayne at the University of California suggests that a number of wolf-like canids diverged from a common ancestor about two to three million years ago. The first grey wolf, Canis lupus, probably appeared in Eurasia sometime in the early Pleistocene period about a million years ago. Around 750,000 years ago, it is thought to have migrated to North America. The dire wolf, Canis dirus, larger and heavier than the grey wolf, evolved earlier and the two co-existed in North America for about 400,000 years. As its prey became extinct around 16,000 years ago due to a climatic change, the dire wolf gradually fell off the evolution ladder and became extinct themselves.
Canis lupus, however thrived and continue to pioneer in new environments and new kinds of prey, probably including a few hominids. Mankind's fear of wolves may be derived from this but in truth, humans have never provided more than an incidental meal in the wolf's pursuit of its favoured ungulate prey. Around 7,000 years ago, the grey wolf became the prime canine predator in North America. Since his role as a hunter remained virtually unchanged through the ages, the wolf became a highly flexible survivor.
According to Busch, R.H., (1998) in the Wolf Almanac:
"It is not known exactly when humans first encountered the grey wolf in North America, but one of the oldest archaeological sites that contains both human and wolf remains in the Sandia Cave in Las Huertas Canyon, New Mexico. The wolf bones there have been dated about 10,000 years old."
The evolution of the domestic dog was subjected to much debate in the scientific circles. Some believe that the dog is descended from the wolf, while others think they evolved separately from a common ancestor. Part of the problem in making hard-and-fast distinction among the wolves and their kin is that all members of the genus, Canis may interbreed under the right circumstances, while other normally different species do not. As of 1998, the American Society of Mammologists recommended that the domestic dog be reclassified as a new subspecies of the wolf known as the Canis lupus familiaris.
How the Skeleton of the Wolf have been Manipulated over the Years.
Art Source From: Wolf to Woof by Andersen, Art and Kenny, Kyle / National Geographic, January 2002, pg.5-7
More questions evolved. Did domestication only take place independently in the Old World and New World and if so, when? There are some genetic evidence that the dog is descended from the wolf and that they domestication of the dog took place several times over the course of history. Biologist Barbara Lawrence believes that the first domestication took place around 12,000 years ago based on archaeological evidence. But some anthropologists and zoologists including Konrad Lorenz believethat humans began to feed wolves about 50,000 years ago, gradually leading to the first domestication of the canids. While the latest articles found in the magazine, Science suggested that domestication might have happened only once, probably around 15,000 years ago.
A recent New York Times article by Wade, N., (2002), 'From Wolf to Dog, Yes, but When?' may have adequately answer the questions posed previously. He suggested the timeline of domestication is probably between 15,000-40,000 years ago based on the study made by Dr. Savolainen. This study examined the DNA from several wolf populations and from the hairs collected off 654 dogs around the world:
"Dr. Savolainen calculates a date for domestication either 40,000 years ago, if all dogs come from a single wolf, or around 15,000 years ago, the date he prefers, if three animals drawn from the same population were the wolf Eves of the dog lineage. Dr. Savolainen believes that dogs originated from wolves somewhere in East Asia, because there is greater genetic diversity, often a sign of greater antiquity, in Asian dogs than in European dogs."
Dogs were probably the first animal to be domesticated, and seem to have assumed considerable importance in early human societies by guarding its master's flocks from marauding predators including wolves! Without a doubt, the link between wolves, dogs, and people have produced some of the most fascinating account in animal literature.
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