Talk:Human evolution
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Please dont think I want to create any problems, but as fas as I can see theres a (BIG) difference in the human evolution and the evolution of Homo sapiens, why I think its incorrect to redirect the page.
The human evolution of course, may start earlier with any Homo or even far back. Stumbling upon this page just becuase I wanted to make an interlink, I do not, (despite my opinion) belive that I could presently make a good article about the human evolution, but if any one does, then please make a language link to the swedish page like: [[sv:Den mänskliga evolutionen]] which is presently on the evolution of Homo sapiens page. Thanks, Dan Koehl 16:56 Feb 8, 2003 (UTC)
This taken from main page:
"Anthropologists currently identify two subspecies of H. sapiens: neanderthaloids, and modern humans (originally identified as "Cro-Magnon Man"). Current evidence suggests that the two subspecies diverged during the fourth glacial period around 40,000 years ago, after which neanderthaloids died out. All human beings today belong to the same subspecies, Homo sapiens sapiens."
Now, I am strongly of the opinion that Neanderthals should be classified as a seperate species, not merely a sub-species, but this is debated so I'm not going do anything with that yet, except maybe strengthen that side of the arguement while acknowledging that it is still debated. But, other parts of this paragraph are just plain wrong. It seems to imply that Neanderthals died out almost as soon as they came into existence 40K years ago. In fact, they existed for at least 150KY, I think rather more; and their fossils are known from as little as 27KYA.
But I don't have nearly enough time nor references at the moment to fully correct this, so I'm leaving it here for now. Je reviendrai. -Aidan Elliott-McCrea
Moved from main page:
Vaccination and other medical advances since the start of the 19th century have caused dramatic improvements in the survival rate of humans. The number of offspring per birth surviving infancy was 0.99 for singleton births, 1.74 for twin births and 2.78 for triplet births, between 1995 and 1997 in the United States. Natural selection is therefore acting to increase the human brood size.
Well, actually, it's not. Those figures show quite plainly that if you're a singleton, you have a 99/100 chance of survival, if you're a twin you have a 88.7/100 chance, and a triplet has a 92/100 chance: that gives any singleton child having approximately a 10% better chance of survival than a twin or triplet. Malcolm Farmer 05:16 Jul 25, 2002 (PDT)
The above comment is on target. the incidence of natural twins has been lessening, not increasing. And notice, a .99% survival does not mean a population decline as long as women have a number of children. SA
This article would be very well served by some literature lists! Good work! -- OlofE
Humans acquired language gene 50,000 years ago. During the last ice age interglacial they spread out of Africa, where they had to fight mute Neanderthals from Europe who were bigger and stronger, but mute. More articulate than these savages they menaged to commit genocide and Neanderthals ceased to exist 20,000 years ago. After that they have domesticated dogs and other animals.
The out of Africa model is well established if not universally agreed on, and the domestication of the dog is pretty solid. The rest of this, though, seems speculative at best.
Removed from article:
- Today's Uzbekistan-Turkmenistan-Xinjiang area had been a cradel of Northern Eurasian and Amerind populations. Most ancestors of modern Europoids, Semites, Iranians, Berbers, Uralics, Siberians, Tibetans, Chinese, Korean-Japanese, Mongolians, Turks and Amerincs inhabited this area which was humid and warm until 17,000 Before Present.
About 40,000 BP, the ancestors of Europoids and other Caucasoids wandered off towards the west, splitting in to Europoid, Middle-Eastern and Berber groups. The population in Central Asia continued to evolve in to Mongolinds. In 17,000 BP, due to the climate turning cold and dry, several waves of migration started off towards the East, some ending up in the American continents, some ending up in Southern China and India, blending with populations of Subcontinental and Southeast Asian origins. The Central Asian population continued to evolve into classical Mongoloids and Tibetans. Finally These groups evacuated the inhospitable Central Asia and branched off into Siberia, Tibet, China and Mongolia around 6,000 BP. Around 4,000 BP, the Indo-Europeans, a group mostly closely resembling, and including the Iranians, re-colonized Central Asian with the help of their advanced pastoral culture, equipped with horses and wheels. Two Indo-European gruops, the Tocharians and Iranians were for a long time masters of the Central Asian steppes, the latter having the supremacy in mobility and number. Mongolian groups adopted the pastoral culture of the Indo-Europeans around 3,000 BP and became very good at it starting 2,000 BP. Several waves of Mongolian migration, often coupled with swift military conquests, started out West, South and East, leaving their legacies in Japan, Korea, China, Yakutia, Central Asia, Afghanistan, India, Iran, Russia and Europe. The above passage is plausible, but nevertheless speculative concerning a period of human history for which we do not have a complete record. But that is not my main objection. I deleted it because it simply does not belong in this article. It is not relevant to the evolution of H sapiens -- it describes migrations of H. sapiens long after they evolved. At best (it would still need accuracy work) it might belong in some other article, say, human prehistory, or paleolithic history. Slrubenstein
Do any articles on Wikipedia discuss the similarity between humans and chimpanzees, and how they should be classified? I want to try and add some info on the following news item, but I am not sure where it should go. Also, is there any discussion here of the significance of that 99.4% figure? I mean, this figure seems to includes exons as well as introns, which would seem a bit misleading. RK
- WASHINGTON (AP) -- Chimpanzees are more closely related to people than to gorillas or other monkeys and probably should be included in the human branch of the family tree, a research team says. The idea, sure to spark renewed debate about evolution and the relationship between humans and animals, comes from a team led by Morris Goodman at Wayne State University School of Medicine in Detroit. Currently, humans are alone in the genus Homo. But Goodman argues, "We humans appear as only slightly remodeled chimpanzee-like apes." He says humans and chimps share 99.4 percent of their DNA, the molecule that codes for life.
- CNN Science website (http://www.cnn.com/2003/TECH/science)
The aquatic ape hypothesis is not generally accepted, and there are a number of points on which it is questionable. Why does this page give it so much more prominence than the conventional view, criticizing only the latter? This seems like a promotional, rather than a neutral, treatment.
Comments on: It is believed by some that human evolution has ended, because humanity as a species no longer has to adapt to its environment: rather, humans are capable of changing their environment to suit their needs.:
The wording seems inadequate; there are far fewer selective pressures to be sure (but this too will cause 'adaptation', i.e. myopia), but what pressures remain prioritize different features and behaviors. Additionally, we might want to differentiate evolution in the form of natural selection and other "natural" mechanisms, and artificial selection and reengineering; the human species is likely on the verge of accelerated genetic change in the form of intentional reengineering; if we define biological evolution as a change in allele frequency in a population over time, then it would be prudent to include this under that process.
- Two points. First, it is, as you say, totally inadequate. It is also false, and ridiculous :-) which is why the weasel words "it is believed by some" have been included. You are welcome to expand this slight introduction to a controversial idea. In this talk page alone, you've tripled the size of it. Second, it is customary to put your talk page comments at the bottom. --Yath 00:14, 27 Jun 2004 (UTC)
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Proposed move
We need to move this page to human evolution; the present name is rubbish, and it does not take into account other hominids. hominid evolution or hominin evolution would also be better but not as good. Dunc_Harris|☺ 09:51, 20 Jul 2004 (UTC)
- No real objection from me, would also pass the Google test nicely ("human evolution": 409,000 vs "evolution of Homo sapiens" 3,570). We could also use the opportunity to integrate/delete/redirect or otherwise incorporate the rather awkward page: theories of the origin of humans, which isn't a true encyclopedic article, nor a proper disambiguation page (references to wikipedia should never appear in the text of wikipedia articles to maximize 3rd party re-use of content, hence the generic text for Template:Spoiler which doesn't mention wikipedia). --Lexor|Talk 13:19, 20 Jul 2004 (UTC)
- I'm good with the move. - UtherSRG 13:45, 20 Jul 2004 (UTC)
No objections for a week, page has been moved. --Lexor|Talk 08:56, 28 Jul 2004 (UTC)
Neanderthals
Hi there,
I found this website via Google http://www.rdos.net/eng/asperger.htm whilst researching whether Neanderthals made a genetic contribution to us. Your site seems to think not
The following is an extract from Almas section on the above site.
The Neanderthal DNA evidence that was reported in the July 1997 Edition of Cell was based on one sampling of DNA taken from a bone. This sampling was also of the mitochondria DNA (mtDNA) which is often utilized for its abundance and that the mutation rate is higher in mtDNA then in nuclear DNA (cell nucleus as source of DNA instead of mitochondria which is a cell substructure).
Mitochondria DNA is also the DNA used in the theory of a “mitochondrial Eve”. This specialized DNA is also only passed on by females.
A sequence of this mtDNA consisting of 379 units was isolated. This was then compared to a human population sampling. Neanderthal DNA varied by 27, there are 55 differences between humans and chimpanzees (Pan troglodyte). This suggests that based on the mtDNA mutation being consistent that humans and Neanderthals separated anywhere from 125,000 to 690,000 years ago, and thus are distinctly separate species. This compliments the theory of “Out of Africa”.
Dr. Christopher Stringer (the lead proponent of “Out of Africa”) does say that taking a sequence of mtDNA of 379 units does not necessarily prove Neanderthals were a separate species. This is based on the fact that human mtDNA contains about 16,500 units (meaning that only about 2.3% was analyzed). He has also stated that this kind of DNA analysis on old cells is controversial due to a possible breakdown of the cells. What follows is a statement by Dr. Stringer : “ The Neanderthal mtDNA sequence thus supports a scenario in which modern humans arose recently in Africa as a distinct species and replaced Neanderthals with little or no interbreeding. But they point out that other genes might tell somewhat different stories. This is certainly possible because, as mentioned, mitochondria DNA is only inherited through females. So genetic heritage passed on from Neanderthal males to present day populations…would not be recorded in that particular DNA.”
Some scientists have stated that if humans populations were isolated from each other then they would accumulate drifts in their mtDNA. This would continue until their physical appearance differed. Taken one step further, their shared ancestor between varied isolated people would appear archaic.
A geneticist named Simon Easteal has stated: “chimpanzees and other primates display much more with-species mtDNA variation than humans do. The amount of diversity between Neanderthals and living humans is not exceptional.” Geneticist Alan Templeton has stated that: “You can always construct a gene tree for any set of genetic variation, but there’s a big distinction between gene trees and population trees.” Population trees being those histories of genes of a group, not individual.
Other DNA work is overruling the “Out of Africa” theory now. Some of which is variations within betaglobin genes and Y chromosome evaluations. Some of this work now suggests expansion out of Africa and interbreeding among populations. Multiregional evolution is now becoming popular as well.
I do not feel qualified to edit the information presently included on your site under the heading Human Evolution. It is that the section below taken from your site may just be behind the times.
Neanderthal Man There is ongoing debate over whether "Neanderthal Man" was a separate species, Homo neanderthalensis, or a subspecies of H. sapiens. While the debate remains unsettled, the preponderance of evidence, collected by examining mitochondrial DNA and Y-chromosomal DNA, currently indicates that there was no gene flow between H. neanderthalensis and H. sapiens, and therefore the two were separate species.
In 1997 Dr. Mark Stoneking, then an associate professor of anthropology at Penn State University, stated: "These results [based on mitochondrial DNA extracted from Neanderthal bone] indicate that Neanderthals did not contribute mitochondrial DNA to modern humans… Neanderthals are not our ancestors."² Subsequent investigation of a second source of Neanderthal DNA confirmed these findings.³
What do you think?
Regards,
Perry (originally posted by User:82.44.184.185 at the Wikipedia:Help Desk and moved by Noisy 12:23, 14 Aug 2004 (UTC))
I think its becoming pretty clear now that Neanderthalis is a different species. Neanderthalis seems to have been outclassed by Homo and competed out of existence. However, they also seem to have had the ability to produce art and jewelery, so they were capable of symbolic thought. Had not Homa wiped them out, they might have been our ancestors instead, so they deserve a mention at least in our evolution
on a different note, dont we need to add a bit about Ardipithecus ramidus ?
Article needs more info on the species which preceded the first Homo species. —Lowellian (talk)[[]] 06:15, Oct 13, 2004 (UTC)
Intro rewrite
I rewrote the entire intro. The old intro was confusing, too specific, and dealt with topics that weren't even about human evolution. In short, the previous Human Evolution Introduction was neither about Human evolution nor an intro. --JPotter 00:58, Jan 28, 2005 (UTC)
Hominid ancestors
The earliest hominids
The Australopithecus genus
The Paranthropus genus
Image:Darwin-chart.PNG - eugh! horrible.
Darwin-chart.PNG
So then guys, evolution involves progression up the great chain of being then does it? Our job as science communicators is made hard enough by our own ignorance. Paleontology and human evolutionary biology has a history of falling for the fallacy of evolutionary progression, and the general public are suckers for it too, so we shold steer well clear of any monkeys to man side-by-side pictures. Find some bones or something. Dunc|☺ 21:09, 26 Feb 2005 (UTC)
to get separate species of humans should exist genetic barrier of infertility.
Human have 10 times longer maturation period, 10+ years. The genetic infertility barriere should be proportional to Generation offspring's if for dog it is 1MY for Human may be 10My. It is perfect with separation of our other cusines (chimps &c)
The fact that each anthropologist want to find new species give us a sytuation that we have tree full of hanging dead humans and no even race betwenn living population.
So dont be racist for ancestors, there is no realy reason to separate them in different species. Especialy H. Neander. Did HN mix? In fact we can say. The other species where whiped out becouse there was no barier of infertility and they mix (which realy mean there was no separated species)
ps.PLs edit typo.
Multiregional hypothesis vrs. out of africa
Multiregional hypothesis needs alot of content added by an expert or student of human evolution. Please come lend a hand, those in the know. (Sam Spade | talk | contributions) 21:04, 4 Mar 2005 (UTC)
Genus Homo
Shouldn't all of the species in this list be consistant in "H." vs. "Homo"? I'd edit, but I really don't know much about taxonomy. --Tydaj 21:29, 7 Apr 2005 (UTC)
Lucy
Recently the article Lucy refered to Australopithecus afarensis. I understand why many would find this acceptable but the fact that it is a name is clearly the primary meaning. I have therefore changed the article and am in the process for changing all lucy links to Australopithecus afarensis| lucy. Trouble is, there's one in the human evolution box, and I don't know how to change its. Can anybody help? (Comment by User:Matthew Mattic)