Am I Understanding the Basic Theory of Evolution Correctly?

[Dagenais]

Don't know if this belongs in Social Sciences or here, so I apologize if it is in the wrong category.

I need someone to tell me about the basic theory of evolution. I remember learning it during the 7th grade, and now I have a bunch of names and facts jumbled in my head.

As far as I know:

Humans did not exactly evolve from "apes" as many claim, but from a creature called the Homo Habilis. This organism resembled that of a mix between an ape and human. Now, from the Homo Habilis came other forms: Homo Erectus, Neanderthal and Cromagnon-man (Spelling?). As each of this forums "evolved", they became smarter with tools and hunting, and more resembled the look of an ugly human.

Since each new form was more intelligent and invented better tools/weapons, people theorize that each new "version" killed off the older or simply dominated hunts so that the older more inferior forms slowly died out.


Am I even close to being correct?

Please "un"confuse me as my class is doing a bit of Geology tomorrow, and I want to make sure I'm ahead or at least understand a tinge of the "evolution" theory.

Thanks.

 

[russ_watters]

Actually, this is a biology question, but that's ok. Yeah, your understanding is pretty good.

 

[Dagenais]

It is!?

I was taught it in Canada in Social Studies.

Then again, in Earth Science.

 

[LURCH]

I'll throw in a little zoology just to make it an even mix; man technically is an ape, as was the primate from which we are thought to have evolved. Also, there is considerable contraversy regarding the Neanderthal as an ancestor. The mainstream thinking now is that Neanertal may have been an entirely separate species that existed at the same time as early Homosapiens. There is much debate as to whether the two species combined through interbreeding, or the Neaderthal simply died out because Homosapiens' more developed brain gave us the edge in competeing for food and living space.

So rather than humans evolving from Neanderthal and then outcompeting them, it is possible (and currently even popular) to speculate that Neaderthal and Hommosapiens evolved seperately, from a common ancestor.

 

[Dagenais]

Wasn't there one after neanderthal, like http://www.mikedust.com/history/cromagnon.html ?

What's the story on them? Didn't they come after the Neanderthal?

 

[Mentat]

Originally posted by Dagenais
Wasn't there one after neanderthal, like http://www.mikedust.com/history/cromagnon.html ?

What's the story on them? Didn't they come after the Neanderthal?

Cromagnons are often considered to be the same as Modern Man, of course, there is the possibility (as LURCH briefly alluded to) that Cromagnons co-existed with Neandertals and that their offspring is Modern Man...I don't think there's a definite answer yet.

 

[Phobos]

Originally posted by Dagenais
Humans did not exactly evolve from "apes" as many claim, but from a creature called the Homo Habilis. This organism resembled that of a mix between an ape and human. Now, from the Homo Habilis came other forms: Homo Erectus, Neanderthal and Cromagnon-man (Spelling?).

Right, modern humans & other modern apes had a common ancestor in the past. That ancestral human/ape-like population branched off into different sub-populations (isolated breeding groups) that followed different evolutionary paths. One path led to H. sapiens, one to gorillas, one to chimps, etc. Our path (which had its own branching in the meantime) included species like H. habilis & H. erectus.

As each of this forums "evolved", they became smarter with tools and hunting, and more resembled the look of an ugly human.

Our path led to higher intelligence, slightly different appearance, less hair, less body strength, better land-abilities & lesser tree-abilities, etc.

Since each new form was more intelligent and invented better tools/weapons, people theorize that each new "version" killed off the older or simply dominated hunts so that the older more inferior forms slowly died out.

Could be. Direct competition like that is one possible reason Cro-Magnons succeeded over the Neandertals. But I'm sure the full reason is much more complicated then that. (e.g., changing climate, etc.) Human populations were small at that time and I think there would be enough food/land to preclude extinction through war/hunting alone.

 

[LURCH]

Regarding the possible separate evolutionary paths of Cromagnon and Neanderthal man have you ever heard of the "aquatic ape" theory? Not accepted universally, nor even buy the majority AFAIK, it is still in a plausible theory.

 

[Phobos]

Originally posted by LURCH
Regarding the possible separate evolutionary paths of Cromagnon and Neanderthal man have you ever heard of the "aquatic ape" theory? Not accepted universally, nor even buy the majority AFAIK, it is still in a plausible theory.

Me? Yep. Like you suggest, it's an interesting idea, but not accepted due to lack of evidence.
http://www.straightdope.com/mailbag/maquaticape.html
I tend to think it's very unlikely, but I'd be interested to see research into it.

 

[sage]

the data i give you here is a little out of date for I'm certain that recently new discoveries have stretched the antiquity of homonidae back a few million years. anyway here goes.

australopithecins were the earliest form of homonids who diverged from apes at about 5 million years ago. they were represented by ardipithecus ramidus(4.4 mya- ancestory disputed);australopithecus anamensis(4.2 mya);australopithecus afarensis(3.6 mya-Lucy is an example);aus.africanus(gracile form evolving from afarensis);paranthropus(robust form evolving from the same, both 3-2 mya).australopithecins were distinct from apes in the sense that they walked upright. their brains did not show any signs of complexity and they did not have any tools. they arose near kenya and later spread throughout east and southern africa corr. to a change of environment from tropical to grassland types.
with the appearance of the first STONE tools we enter our genus the Homo.homo habilis is the first species of homo who arose at about 2.5 mya in eastern africa(kenya, etheopia etc.)it is possible that australopithecins coexisted with habilis till 1.5 mya before climatic cooling which had triggered the evolution of habilis wiped them out.habilis had a larger and more complex brain and used to scavenge for meat by driving off predators from carcass(and perhaps hunt small prey),their diet was cheifly veg. though.because they lived in large groups it is possible that their commucation skills have also increased,but that is not certain.
at 1.7 mya a new species with astonishingly modern features appeared. 6 feet tall and brain half as large as us it is homo ergaster first discovered in kenya.a few thousand years later it is followed by innovation of sophisticated stone tools like the hand axe. the first evidence of use of fire also come from ergester at about 1.5 mya.soon came homo erectus which was the first homonid to come out of africa and colonize eurasia.
shall be continued later.

 

[Phobos]

Originally posted by sage
it is possible that australopithecins coexisted with habilis till 1.5 mya before climatic cooling which had triggered the evolution of habilis wiped them out.

It's possible that A. robustus (an offshoot of A. africanus) survived to 1 mya (outlasting H. habilis and living in the time of H. erectus)

 

[Damion]

Originally posted by Phobos
http://www.straightdope.com/mailbag/maquaticape.html

ROFL! this article is hilarious.

 

[Nereid]

LURCH wrote: *SNIP
Also, there is considerable contraversy regarding the Neanderthal as an ancestor. The mainstream thinking now is that Neanertal may have been an entirely separate species that existed at the same time as early Homosapiens. There is much debate as to whether the two species combined through interbreeding, *SNIP

IIRC, studies of mitochondrial DNA show that there is no Neanderthal mother - we are all descendants of African Eve (who lived and died ~200,000 years ago). Not conclusive; for example, there are surely many isolated population groups whose mitochondrial DNA hasn't been tested, and we know nothing (yet) about whether there is but one African father.

 

[Phobos]

Originally posted by Damion
ROFL! this article is hilarious.

Their articles are always hilarious, and more importantly, accurate.

 

[Phobos]

Originally posted by Nereid
IIRC, studies of mitochondrial DNA show that there is no Neanderthal mother - we are all descendants of African Eve (who lived and died ~200,000 years ago). Not conclusive; for example, there are surely many isolated population groups whose mitochondrial DNA hasn't been tested, and we know nothing (yet) about whether there is but one African father.

It's an interesting debate. It seems like every few months, a new article comes out with evidence that Neandertals were or were not part of our ancestry. I don't follow it too closely, but the last article I saw (Jan 2004) said Neandertals did not interbreed with Cro-Magnons based on anatomical evidence and comparisons of fragmentary Neandertal DNA.

I thought there was some evidence of a single father too (based on markers on the Y chromosome). I'll have to check around for details...

 

[maps]

Perhaps the following will be of help to Dagenais, although a little late, in his search for information on Cro-Magnon Man

A Short History of the Basque
by Martin de Ugalde

http://www.buber.net/Basque/History/shorthist.html


Archaeological and ethnographic findings indicate that Basque [people] evolved from Cro-Magnon [...] in this area over a period dating from about 40,000 years ago until distinct features were acquired approximately 7,000 years ago. Two thousand years later the sheep, not native to these lands, was introduced and horse and cattle farming came into being, as shown by Adolf Staffe. These circumstances made it necessary for the people to travel periodically and cultural contacts were thus made.

This period in the history of the Basque people can only make sense if it is studied in conjunction with the cultures of the surrounding areas, in the basin of the River Ebro and the region of Aquitaine.

Jose Miguel de Barandiaran states "This area is of particular importance in Basque archaeology and linguistic history as it coincides with the area of seasonal migration of flocks in search of pastures in the Pyrenees and where Basque place names are found in general." Luis Michelena reports that the Basque language has been spoken by these peoples since around 6,000 B.C. Basque was spoken in the whole of South Aquitaine and eastwards, to inside Catalonia (proved by inscriptions and place names). From the sixth century B.C. Indo-European culture wiped out all the pre-Indo-European languages spoken in Europe up to that time, with the exception of the Basque language.

Serious cultural and political problems arose from the above circumstances.

Rand McNally's linguistic map and the Goetz's Universal History divide up the languages spoken in the world [I think he means Europe here - Blas] as follows: Germanic, Slavonic, Celtic, Romance, Mongol, along with those spoken by the Albanians, Arabs, Greeks, Lithuanians, Latvians, Berbers, Armenians, Caucasians, Iranians and Basques.