What is a species?

[flobadob]

Every now and then you'll hear that a new species of something has been found, like spider or something. But what differentiates species? Also I'm wondering are there different species of humans? Is someone born and living in the Amazon a different species to someone from Europe?

[Davethedog]

http://en.wikipedia.org/wiki/Species

[wildwood]

A species is one group of life form that generally has genetically altered so much that it is unable to leave viable progeny when breeding with a another species. If they look different due to geographical adaptation but are still ably to breed fertile progeny, they are classed as sub-species.

The new species found should really be termed as discovered, not found. It has been there all the time. There are still many unknown species of life forms to be discovered, especially in the insect and ocean floors.

All human are still the same species. In all other life forms we would be different sub-species but this is just not done in Society.

[beso]

Wildwood is incorrect. Humans do not have sub species because the differences across the global population are trivial. People in remote areas once represented a separate population but even that is becoming academic in a highly mobile world.

To put it in perspective, a raging debate at the moment is whether the domestic dog and Grey Wolf should be two subspecies if the same species.

Neanderthals and modern humans are considered by some to be only separated as subspecies.

It is very difficult to draw a line.

[wildwood]

I do not understand your reasoning beso. How can you say the difference between an Eskimo and an African bushman is trivial, each dramatically adapted to their individual environment, both physically and mentally.

The Neanderthal branch of early Man died out, but not before interbreeding with the ancestors of the present Homo sapiens. There are well over a dozen separate species of the Homo genus documented, but in reality a new species is not an instant event and in Nature it takes many thousands of generations for subspecies to become a separate species in their own right.

[Calibax]

The difference between an Eskimo and an African bushman is far less that the difference between a chihuahua and a great dane which are most certainly the same species and not sub-species.

[wildwood]

calibax, dogs breeds (and other domestic animals) would never have evolved so in Nature, they are bred to show certain characters as decided by Humans, not in accordance with their natural environment as happens in real evolution.

[flobadob]

It seems like there is little agreement here.

[Answerprancer]

"Species" is a sub catagory of an indexing system that we have applied to all living organisms, by my understanding.

[boxtops]

It's not a question of agreement, flobadob, it's a definition - humans are a species on their own - Man.

[Answerprancer]

There is a diagram that explains here:
http://en.wikipedia.org/wiki/Genus

[flobadob]

Yeah boxtops, but why are there different species of spiders and birds etc? And not humans?

[boxtops]

I can't answer that.

[jomifl]

Flob...humans are a species of primate, just as raft spiders are a species of spider. you are confusing species with genera and families.
I agree with Beso and I don't think you can even say that there are different races of humans, what we call races are just people with a particular collection of characteristics. 'Negros' are dark skinned but in just about every other way there are huge differences between them. Australian Aboriginals are dark skinned but they are not 'Negros'.

[Answerprancer]

LOL "Flob"

[flobadob]

Yes jomifl. What I don't get is, take your example, raft spider is a species of spider, and then another type of spider is a different species of spider, okay. However, why not as you say, *** is a species of human and white people are a different species?, just for arguments sake. I'm finding it hard to distinguish the difference in, when there is a species change involved. Is it something that we just say when talking about different varieties of animals and simply don't use the term when describing different varieties of humans?

[wildwood]

Flob, you need to remember that biological classification is a man-made system and Nature doesn't always adhere to that. It is impossible to say when one species spreads out and becomes isolated from its kindred, thus altering to its individual environment so become biologically different from the species where they come from and become a species on its own right. This takes many thousands of generations, but can happen relatively quickly if say one species is divided by a Natural disaster so contact between the two groups is severed.

Horses and donkeys are different species and can breed with each other but the progeny is generally sterile. They are thus in the same Genus; Equus, but a different species. The identical Genus of both tells us that they have a kindred ancestry millions of years ago. Over this period they have become so different from each other that eventually they became separate species as they are now very different.
Again, a species is just a name for a type of life that is different for a similar type of life but has been separated and have altered genetically.

Sub-species is just another made up name for groups of organisms that have only recently started changing. The domestic dog is very much able to successfully breed with any of the wild wolf groups, thus indicating that they are the same species but the humans, being what we are, have chosen to put the different types of wolf in sub-species and give the domestic dog its own tag Canis lupus familiaris. The African hunting dog has become so different from the Wolf since European/African continent separation many millions of years ago, that it is not only a different species from the wolf but also the Genus. They do however share the same Family classification.

The different races of humans are indeed the same species but if they were any other animal the races would be termed sub-species by us. This ofcourse is not done among humans but was the ca

[wildwood]

but was the case not so very long ago when slaves were considered to be a sub-human.

[The-Toff-]

What an excellent answer wildwood.

[beso]

The classification of slaves as sub-human was a political expedience and does not present evidence to support the notion of human subspecies.

Although a South African does look very different from an Inuit or someone from Tierra del Fuigo, the variation is a continuous trend. The South American is very like the North American, who is quite like the Oriental, in turn the central European and so on.

This is a characteristic of geographical variation due to genetic drift within a monotypic species rather than separate subspecies.