The dog (Canis lupus familiaris) is the domesticated cousin of the gray wolf. In fact, the genus species name for the dog comes from the Latin word for wolf, lupus. From an evolutionary perspective, dogs filled an important role to early man, providing invaluable information during hunts with their superior olfactory and hearing senses. Not only that, but the domesticated dog has always provided companionship, which is why dogs are the most popular pet in the world today. Over time, as is the case with many species, dogs have adapted to different climates and environmental conditions. It is for this reason that there is such a wide variety of different breeds, each with their fair share of advantages and disadvantages. Dogs are predominantly carnivorous, but have adapted to eat autotrophic organisms as well.