Posted on 03/25/2015 10:01:56 PM PDT by Steelfish
Study Shows Humans Are Evolving Faster Than Previously Thought
Hannah Devlin 25 March 2015 Humans are evolving more rapidly than previously thought, according to the largest ever genetics study of a single population.
Scientists reached the conclusion after showing that almost every man alive can trace his origins to one common male ancestor who lived about 250,000 years ago. The discovery that so-called genetic Adam, lived about 100,000 years more recently than previously understood suggests that humans must have been genetically diverging at a more rapid rate than thought.
Kári Stefánsson, of the company deCODE Genetics and senior author of the study, said: It means we have evolved faster than we thought.
The study also shows that the most recent common male ancestor was alive at around the same time as mitochondrial Eve - the last woman to whom all females alive today can trace their mitochondrial DNA.
Unlike their biblical counterparts, genetic Adam and Eve were by no means the only humans alive, and although they almost certainly never met, the latest estimate which gives a closer match between their dates makes more sense, according to the researchers.
When the overall population size is stable as it has been for long periods in the past - men have, on average, just one son, and women, just one daughter. This means that for any given man, there is a high chance that his paternal line will eventually come to an end. This means any male descendants, for instance his daughters son, would have Y-chromosomes inherited from other men. If you travelled back far enough in time, the theory goes, there would be only one man whose paternal line extends unbroken to the present day: this man is Y-chromosome Adam.
(Excerpt) Read more at theguardian.com ...
Children that grow up in high density cities are smaller in all dimensions than people that grow up in the countryside. It’s not just their bones but their organs as well, including their brains. The average Republican is taller and smarter than the average Democrat, which explains many things.
Max Headroom likes this.
Scientists reached the conclusion after showing that almost every man alive can trace his origins to one common male ancestor who lived about 250,000 years ago. The discovery that so-called "genetic Adam", lived about 100,000 years more recently than previously understood suggests that humans must have been genetically diverging at a more rapid rate than thought.No, it means parsimoniousness in the genetic studies are all about researcher bias or extrapolation from too-little data, e.g.:
Study entropy and get back to me.
OK.
It still claims that the Homo Sapien “Adam” could be 174,000 - 321,000 years old.
It still claims that previous studies estimate "Adam" to be 500,000 years old.
No mention of the African fossil record for Homo Sapiens, which, as far as I know, goes back just 200,000 years.
Yes, I agree.
But that's not what the article is about.
It says the genetic “Adam” for all living humans was alive 170,000 - 320,000 years ago, and that previous studies claim as much as 500,000 years ago.
All living humans are Homo Sapiens, and the Homo Sapien fossil record goes back just 200,000 years, or so I thought, anyway.
From the book The Neanderthals by Friedemann Schrenk and Stephanie Mu"ller (2005, English trans. 2009), the Homo sapiens of Africa are descended from Homo heidelbergensis (800,000 B.C. on), a late form of Homo erectus. In Europe Homo heidelbergensis developed into Homo neanderthalensis (or Homo sapiens neanderthalensis).
“It still claims that the Homo Sapien Adam could be 174,000 - 321,000 years old.”
No. Those are the boundaries on the accuracy of their measurements. They are happy that the dated age of ‘eve’ is in the range.
The study, published in Nature Genetics, put the new age for genetic Adam at between 174,000 and 321,000 years ago. Genetic Eve is thought to have walked the Earth around 200,000 years ago: well within the new error margin for Adam.
It gives us enormous confidence to have a timeline that is similar, said Stefánsson.
“It still claims that previous studies estimate “Adam” to be 500,000 years old.”
Actually, it states that previous dates ranged from 50,000 to 500,000 years ago. But so what. It has nothing to do with their study.
Previous dates for ancestral Adam ranged from far more recent, just 50,000 years ago, right back to around 500,000 years ago, with some estimates showing major mismatches with the dating of ancestral Eve.
Sixty eight percent (68%) of all Europeans have male haplogroup R1b DNA. This is because haplogroup R1b men have more boys than girls.
If that's correct, someone needs to explain how the Homo Sapien “Adam” can be dated at 320,000 years in one study, and 500,000 years in a different study.
If there are Homo Sapien fossils that go back 320,000 years, or 500,000 years, I would like to read the research so I can update my knowledge.
Yes, I still agree.
But the article clearly indicates that the Homo Sapien “Adam” was himself a Homo Sapien.
My question - how can the Homo Sapien “Adam” predate the earliest Homo Sapien fossils by hundreds of thousands years?
Fixed it for them.
Only a very tiny fraction of prehistoric animals or people have fossil remains that still exist, and only a tiny proportion of existing fossils are discovered...so it’s understandable that there could be significant gaps in the evidence that has come to light.
Bookmark
Evolutionary time line
http://www.proof-of-evolution.com/human-evolution-timeline.html
http://www.proof-of-evolution.com/evolution-of-man.html
“My point is - and was - that it’s my understanding that Homo Sapien fossils go back just 200,000 years. If that’s correct, someone needs to explain how the Homo Sapien Adam can be dated at 320,000 years in one study, and 500,000 years in a different study.”
My point was that the mention of 500,000 was not sourced and was not defended by the article. As for dating I provided a source and the first paragraph. Please read the rest of the section on “Estimates”.
Estimates[edit]
Current (as of 2015) estimates for the age for the Y-MRCA are roughly compatible with the estimate for the emergence of anatomically modern humans some 200,000 years ago (200 kya), although there are substantial uncertainties.
http://en.wikipedia.org/wiki/Y-chromosomal_Adam
And 100kya, the population of the planet (HSS) was less than 10k people, as the ice age ground on.
Hmmm.
Why is it assumed that the bigger and/or taller you are the more evolved you are? It is more a matter of survival qualities (within a species). At a given time and place larger people may survive and flourish over smaller people. At a different given time and place smaller people may have the advantage. One, though, is not inherently more “evolved” than the other.
Good nutrition is not necessarily genetic change.
The US had tallest folks in the world after WWII. Now it is the Netherlands. US has too many immigrants from poor nutrition areas.
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