KINGDOM: Animalia

Animals are defined as creatures without rigid cellular walls who move, ingest food for energy and are (usually) multicellular. The Animal Kingdom is large and varied. We are a part of it and so are our pets.

PHYLUM:Chordata

The phylum chordata is easy to distinguish- we are a part of this group, too. We have spinal cords. A creature with a spinal chord is a vertebrate an animal without one is an invertebrate. At this point, you, your dog, frogs, birds and even mice are all related.

CLASS:Mammalia

Mammals are characterized by several features. One of them is fur. Hairy creatures like humans and dogs are mammals- but not just because of their hair. Sweat glands, three middle ear bones and something called a neocortex also characterize mammals. The neocortex is a part of the brain that has six layers. It is the part that controls motor skills, reasoning, perception, thought and in humans, language.

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There are five mammalian species that lay eggs, but the rest give birth to live, squirming young. Mammals are further divided into subclasses: theria and protheria.

Subclass: Theria

Therias are placental mammals and marsupials like the kangaroo. Therians have external ears, suckle their young with nipples and have a secially designed ankle for range of motion. They are further classified by their teeth.

Order: Carnivora

At this point, we separate from our best friends. We belong to the order of the Primates, while dogs branch off into the same group as bears, cats, weasels, elephant seals and pandas. Most carnivorans live on land and have claws. Their defining characteristic is their sharp teeth.

Suborder:Caniformia

Caniforms are believed to have evolved from an animal that lived in the trees and ate a varied diet. They were similar to martens and called Miacis. 65 to 55 million years ago, these creatures most likely lived Caniforms are separate from the Feliforms because of their teeth and claws. 50 million years ago, dogs and cats were the same animal.

Family: Canidae

Canines are defined by their teeth. The first real canine fossil that we have found dates to about 40 million years ago and is called Prohesperocyon wilsoni which branched off into three groups, one of wich was the Caninae, the party that gave rise to modern dogs and wolves.

Genus: Canis

The genus Canis is made of wolves, jackals and dogs. Several animals belonging to the group are now extinct.

Species: Canis Lupus

Canis lupus is the Grey wolf. This is the creature that ate Grandma in the fairy tale. He is your dog’s grandfather. Having survived the last ice age, about 300,000 years ago, it is unclear whether they will survive humanity. They are an endangered species today, although they once roamed all over the world.

We don’t know for certain when dogs were domesticated, although the archaeological evidence shows that it was most likely no less than 15,000 years ago. It is also uncertain which subspecies of Gray wolf was the first to be domesticated.

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Subspecies: Canis Lupus Familiaris

In the 15,000 years or more of our symbiotic relationship, we have bred the dog until it has become the most varied land mammal on earth. Someone from another planet might never guess that an English Bulldog, a Pappillion and a Poodle were the same animal. Yet, they are.

The oldest dog breeds, like the Basenji and the Lhasa Apso originated in Asia and Africa, pinpointing these areas for domestication.

From their wolf ancestors, dogs acquired a strong sense of hierarchy and the ability to communicate through body language. Since dogs are social creatures themselves, it doesn’t seem unlikely that they would be the animals for us. Some scientists suggest that domestication of dogs began when dogs scavenged the cooking fires of mankind, losing their shyness of the “two-legs”.

In any case, dogs have a long and noble history and they have carried some of their instincts with them. Millions of years ago, we shared an ancestor with these creatures but today we share a lot more.

Dogs are amazing. They have been that way for a very long time.

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