Why is there only one species of human?

[tomspug]

I've been thinking about evolution and the bigger picture of life, and one question that's come up in my mind is, if we evolved from lower forms, why is it that none of them survived, or branched out into different species within the same family? Pretty much every other animal on the planet demonstrates this... It's true that isolated people groups can develop defining physical characteristics, but there doesn't seem to be many examples of competing forms of humanity (if there was ever a competition).

 

[Caladan]

The Neanderthal (IPA: /neɪˈændərtɑːl/, also with /niː-/ and /-θɔːl/), or Neandertal, is an extinct member of the is a Homo! genus that is known from Sedo Domain Parking - Sedo GmbH specimens found in Europe and parts of western and central Asia. Neanderthals are either classified as a subspecies of humans (Homo sapiens neanderthalensis) or as a separate species (Homo neanderthalensis).

The mighty Wiki

One of the popular theories is, that modern humans pushed neanderthals into extinction.

modern human beings are all thats left of the different hominids that walked the lands in the last million years.

 

[Nepenthe]

What Caladan said.
Homo sapiens and neandertals co-existed for as long as a thousand years. There's still some controversy over whether they were wiped out by modern humans or their lineage simple trickled out due to a variety of environmental factors.

I could also point out that other primates have occupied other niches and have been highly successful: bonobos, chimpanzees, gorillas, prosimians, etc., etc.

 

[Caladan]

ROFL, the beginning of that wiki entry, sure is strange..
thats the second time im pasting it, yet it comes out in that naughty way

 

[Yerda]

There are a few now extinct members of Homo. Home ergaster, Homo erectus, and the neanderthals spring to mind. Painted Wolf would know all about this, no doubt.

 

[Autodidact]

Scientists estimate that around 99% of the species that ever existed are extinct.

 

[themadhair]

I've been thinking about evolution and the bigger picture of life, and one question that's come up in my mind is, if we evolved from lower forms,<1> why is it that none of them survived <2>, or branched out into different species within the same family?

1)Lower form makes no sense with respect to evolution.
2)I could be wrong about this, but aren’t our fellow primates not those surviving species?

 

[9-10ths_Penguin]

2)I could be wrong about this, but aren’t our fellow primates not those surviving species?

Depends on your point of view, and what you consider makes a species "human" or not. The order of primates covers a pretty wide swath of species and genetics.

There aren't any other living species in the genus Homo, but there are a number of other prominent examples where there's only one surviving species of the genus.

 

[themadhair]

Depends on your point of view, and what you consider makes a species "human" or not.

True. I think I remember a study that mentioned how the genetic differences between some members of the cat family was greater than the differences between humans and chimpanzees.

I can’t find that study goramit.

 

[tumbleweed41]

YouTube - Peter Gabriel - Animal Nation

Perter Gabriel and his song about 'jamming' with the Bonobo Apes

 

[Breathe]

Because Neanderthals got pwned.

Personally, I suggest cloning them back into existence.

 

[Yerda]

Because Neanderthals got pwned.

Let's not get too technical.

 

[MSizer]

Humans are too dominant over our environment to specify. We are able (thanks to technology and taming of other animals) to travel great distances, and thus we frequently spread our genes amongst each other in all areas we inhabit. We can't specify if we aren't seperated from each other. If (more likely when) we start enhabiting other planets, the chance for specification may increase, depending on how easy it is to move among different planets. If it is difficult to move between planets, and the enviromental forces are significantly different among planets, speciation becomes more likely (although it would take a hundred thousand years or more).

 

[Nanda]

From Wikipedia:

It has even been proposed that troglodytes and paniscus belong with sapiens in the genus Homo, rather than in Pan. One argument for this is that other species have been reclassified to belong to the same genus on the basis of less genetic similarity than that between humans and chimpanzees.

I've read this other places as well, in various books about Chimps and Bonobos.

 

[Valjean]

I've been thinking about evolution and the bigger picture of life, and one question that's come up in my mind is, if we evolved from lower forms, why is it that none of them survived, or branched out into different species within the same family? Pretty much every other animal on the planet demonstrates this... It's true that isolated people groups can develop defining physical characteristics, but there doesn't seem to be many examples of competing forms of humanity (if there was ever a competition).

First, any time someone uses a term like "lower forms" biologists throw up their hands in frustration. Evolution is not progressive, it's pragmatic. It's about adaptation, not higher or lower.

For most of hominid history there was more than one species walking around. Ours was probably just more technologically adept, or more aggressive, and more generalized than the competition. We, and climate change, wiped them out.

 

[painted wolf]

We don't play well with others. :sad:

wa:do

 

[MSizer]

Actually, it just occured to me that you could ask the same question of any other speicies on the planet. There is only one species of each species.

 

[Runewolf1973]

I've been thinking about evolution and the bigger picture of life, and one question that's come up in my mind is, if we evolved from lower forms, why is it that none of them survived, or branched out into different species within the same family? Pretty much every other animal on the planet demonstrates this... It's true that isolated people groups can develop defining physical characteristics, but there doesn't seem to be many examples of competing forms of humanity (if there was ever a competition).

I don't know, but have a look at this...Differently adapted or evolved, but human nonetheless.

Pygmies - Wikipedia, the free encyclopedia

 

[painted wolf]

This is an ethnic group... NOT a species!

wa:do

 

[Runewolf1973]

This is an ethnic group... NOT a species!

wa:do

They are human, humans are a species. Sorry, I did not mean to say they were a different species if that is what it sounded like, that is not what I meant. Yes they are an ethnic group, but it is possible that as humans, they evolved with some different traits from the mainstream. I was just simply trying to point out that evolution plays a role in humanity as it does in all other things. These slight genetic variances in a species, is that not what eventually causes the evolution of a whole different species? Where will evolution take us? 500,000 years or more from now, could we still call ourselves "human"?