Did you realize that every dog has the same name? No, we're not talking about Fido, Spot, Scooby, or Lassie. We're not even talking about "dog" as a name. Instead, we're referring to the scientific name of all dogs: Canis lupus familiaris.
That's quite a mouthful of Latin, so it's easy to see why we use "dog" or something more specific. Scientific names identify creatures by their specific genus and species. Within a particular type of animal, there can be various different species all with different names.
Take badgers, for example. Depending upon where you are when you come across a badger, you could find yourself looking at a Mellivora capensis (honey badger), Taxidea taxus (American badger), or a Meles anakuma (Japanese badger).
Of course, if you run into a badger in the wild, you'll probably wish you had another Homo sapiens with you. What's that you ask? It's another human being, just like you. As humans, our scientific name is Homo sapiens.
Does that seem kind of silly to have a scientific name for human beings? After all, there's just one of us, right? It's not like we're going to confuse a human being with a badger. Scientists would tell you, however, that a human being needs a scientific name just like all the other animals.
Of course, we don't have videos or writings from the beings that lived millions of years ago. What scientists do have are fragments of what they left behind in the form of fossilized bones. Using ancient fossils, scientists have worked hard to piece together a picture of what early human history might have looked like.
For example, scientists think the first members of the genus Homo, an ancestral species thought to be closely-related to modern humans known as Homo habilis, originated in Africa approximately 2.8 million years ago. Other ancient human species have also been identified, including Homo neanderthalensis, Homo erectus, and Homo ergaster.
For many years, scientists believed that one species of human replaced another as evolution took place. New fossil evidence, however, now appears to support the idea that Earth may have been home to more than one human species at a time.
For example, scientists believe that up to four Homo species may have coexisted on Earth as recently as 40,000 years ago. Can you imagine Homo sapiens, Homo neanderthalensis, and possibly two other unidentified Homo species all living on Earth at the same time?
As for us modern humans, scientists believe Homo sapiens began to develop in East Africa around 200,000 years ago. Although the first Homo sapiens likely looked like us, they probably didn't develop modern behaviors until about 50,000 years ago. Since all other species of the genus Homo are long extinct, Homo sapiens is left to carry on into the future!