Half-Life

I need this question answered:


Why are there only one species of humans but a lot of species of bird, insect, mammals, etc. Why only one species of humans?

If this is a stupid question, don't blame me, blame the teacher. This will be my first time talking about eovlution in a group tomorrow.

Daggah

There were more species of humans, but the more intelligent humans (us) dominated the lesser species and drove them to extinction.

That's the short answer. I'm sure someone will be around to explain it in more detail.

Dr.GH

You are a bit late starting your homework, neh?

Take a look at some of these web pages;

<a href="http://www.humanevolution.f2s.com/" target="_blank">like this one</a>

<a href="http://www.uchicago.edu/aff/mwc-amacad/biocomplexity/" target="_blank">and this one</a>

<a href="http://www.talkorigins.org/faqs/homs/" target="_blank">and this web page too</a>

<a href="http://www.mnh.si.edu/anthro/humanorigins/faq/Encarta/encarta.htm" target="_blank">one last page</a>

Oh, and start earlier next week.

[ April 14, 2002: Message edited by: Dr.GH ]</p>

Half-Life

Yes, I stay up late on school nights. I don't really like sleeping. Thank you for the links.

tronvillain

A few points:

• Asking why there is only one species of human is like asking why there is only one species of orangutan (there is only one of any species, by definition).
• Mammals are a class of organisms which includes humans, while birds and insects are other classes of organisms comparable to mammals.
• There may have been other species quite similar to humans, but they are extinct, and other primates are quite similar to us in any case.

Quetzal

One to add to tron's post:

Ask your teacher why s/he thinks there's only one extant species of human? If it weren't for creationists demanding a separate lineage for Homo, we could easily include at least chimps and bonobos in the "human" line - or include humans in the Pan line based on genetic, morphological, and even some behavioral evidence. That ought to get the argument going...

[ April 15, 2002: Message edited by: Morpho ]</p>

big d

It seems to me (I'm not knowledgeable regarding science) that if one looks at Africans, Asians, Aborigonies, Caucasians, etc, one can see there are huge differences that show man has evolved in different ways, in different geographical areas, at different speeds, with different characteristics. We are all human but we are also very different.

Ergaster

The simple answer is that all the other species of humans (and there were a considerable number of them, depending on how broadly you want to define "human") went extinct.

The more specific answer relates to how modern humans are highly adapted to cope with extremes of environmental variability, to the point that we can manipulate our environment to suit us, rather than have to adapt to specific environments. This is something that no other species (including extinct humans) can do (at least, not to a great degree). That should give you a starting point.

(And pay particular attention to stuff by Rick Potts, such as on one of the links that Dr. GH gave you).

And btw: how *does* your teacher define "human"?

Deb

[ April 15, 2002: Message edited by: Ergaster ]</p>

Non-praying Mantis

Most of the differences between the different "races" of humans are probably caused by very few genes. ALL humans share approximately 99.5% of their genes, including introns and other non-coding sections.

Differences between race are most evident in skin color, facial features, and a few other genetic quirks such as sickle cell anemia and cystic fibrosis genes. The reason that these differences SEEM to be very important is that most of these are highly visible to us. Genetically we are very close and are all capable of interbreeding.

NPM

Non-praying Mantis

Then you have something in common with my students. I just gave the first lecture on evolution in my class today.

NPM