Why is there only one human species?

Question

Think of other species like beetles & there are 1000's of varieties, cats have many different members of the cat family.
yet humanity only has the one.

why is this?

Answer 1

Your question is very good. Here is what I have found out:

Humans are quite unique among animals, in that our genes per individual are for all intent and purposes, mostly exact. This is the result of humanity being a very recent evolution in Earth's history.

As a consequence of our gene pool's size, there are very few varieties possible. Our evolution confines us to re-invent with genes we already possess or to express genes that are not expressed in the mean population but have been carried from previous states.

In order for a trait to evolve, you need a small population, confined breeding, a selective pressure, and a lot of time. Humans have become more global and have few selective pressures, except for the demands of society and the requirement to pass on genetic information to the next generation. As a result, humans are mostly stuck.

Our evolution is now entered upon how we use what we have rather then brand new traits unless spontaneous mutations occur (very slow), or we take control of our own genetics. At least for the foreseeable future.

Answer 2

'Beetles' are not a single species with lots of varieties - in fact the word describes a whole order of insects.

The equivalent level of classification for humans is 'primates' - this includes monkeys, apes and lemurs (hundreds of species in all). Cats, in turn, are members of the order carnivora, which also includes dogs, bears, weasels and seals.

That said, there are more different species of beetles than any other order. This led the great biologist JBS Haldane to joke that if there was a Creator, he had 'an inordinate fondness for beetles'.

Answer 3

Well, first of all, taxonomy is a subjective classification system. There is only one species of human because we said so. In this same respect, there is only one species of dog, one species of domestic cat, one species of horse, etc... However, since there are clearly huge differences between all of the individuals of these species, those who raise these animals have further separated them into breeds. The breed classification, though, is not recognized by evolutionary biology.

The problem is thus: one of the cherished criteria of taxonomy is that individual animals of the same species must be able to mate with each other successfully. Since all humans can do this, no one will separate us into different species.

By the way, ethnicities is essentially a breed-like classification that humans have developed for ourselves.

Answer 4

You're mixing things up. Beetles are not a Species... There a many different species of beetles as you said.

Humans are Primates. There are many primate species out there too.

But there is only on Homo sapiens in primates.

Try finding the definition of a species, kingdoms, families, etc, and you will understand.

Answer 5

There are more species of beetles than any other creature we know. As you go up on the "complexity ladder" the number of different species declines. Since humans are on "top" there is only one. This is not a reason, but an observation.

Answer 6

Different kinds of cats is nothing to do with (alleged) evolution. It is nothing more than natural selection. In fact lions and tigers are different species but can interbreed,showing that the label of species is to some extent arbitrary.

There was probably only ever one kind of big cat.
There has certainly only ever been one kind of human - descended from Adam and Eve.

We are not related to apes. This is a philosophical idea not supported by the evidence. Check for yourself and you will notice that all hominid fossils are either clearly man or clearly ape. Despite wishful thinking no missing links have ever been found.
http://www.creationontheweb.com/content/view/3048/

Answer 7

Humans are members of the primate family. Humans are a species. We're a species of great ape. Gorillas, chimps and orangutans are other members of the great ape family. Ethnicities are kind of like human breeds/species as many are physically very different although I would never like to have to say my 'breed' is Caucasian. Although if a pathologist looked at my skeleton after the rest of me has rotted away they could still say I was Caucasian because of physical traits in my bones, same way they could tell I was female, same way they can tell the difference between an alsatian skeleton and a greyhound skeleton.

Strange question but it makes you think

Answer 8

Wrong! we are not merely a species! We are a sub species of the primate. Evoloution has enabled us to walk on our feet and to be smarter than other primates. Humans then merely adapted to the climate and the regions in which they reside which causes the variations in skin, hair and eyes!.

Answer 9

well in evolutionary terms we haven't been here that long compared to other families of species, so we haven't really had enough time to separate into different species.
when our species evolved it was so successful that the others died out.
speciation occurs when animals become reproductively isolated,preventing genes from being passed, human populations are no longer isolated thanks to technology so there are no barriers preventing genes spreading.


why are people taking this as a racist question? its science

Answer 10

There isn't just one. Homo neanderthalis existed with Homo sapiens at one time. Earlier there were other humans, e.g. Homo habilis. Only one species lives now, but there were others in the past.