Pretty interesting...curious of your thoughts on this

bullethead

Of the hard cast variety
When you take those findings and compare them to other studies that included catastrophic events that occured throughout history which had major impacts on species.....it makes a lot of sense.
 

oldfella1962

Senior Member
indeed, almost nothing is linear & steady. Everything has peaks, valleys, tipping points, etc. And environmental catastrophies (including extinction events) occur more or less randomly. True one of the better known extinction events was what killed the dinosaurs but there were others more recently. If one occurred 100,000years ago then it makes sense that most species alive at that time went extinct leaving what we have now.

Still I hope a lot of scientists jump on this to research it some more - it is a fascinating find!
 

GeorgiaBob

Senior Member
I have seen some of the individual studies that were indirectly referenced in the article. The studies I saw, consistently addressed the difficulty in "dating" the various species genetic common ancestor. Instead of these studies all "agreeing" on a "9 out of 10 species originated" 100,000 years ago, what I was reading asserted a common "modern" intersection for most currently existent species - a mitochondrial "Eve" if you choose.

The "100,000" years claim in the story is a misstatement of fact. The researchers were able to identify a "range" for the number of generations in which no significant genetic mutation was present in the COI. It then took some playing around with estimates for the fertile period within a specific species, adjustments for variation based on guesses on species stress, environmental differences, and climate changes, to align that GUESS about the number of steady COI generations with a guess about the number of years that translates into. The results were almost all "modern" - meaning probably less than half a million years - and almost all were not recent - meaning not less than 20,000 to 50,000 years. The fact that the writer picked 100,000 and applied it to all (actually possible, but very unlikely) tells me that the author was trying too hard to tell a story and less interested in facts!

The studies do NOT imply that 9 out of 10 species existent today did not exist 110,000 years ago. The resulting data simply and specifically implies than in most modern species genetic diversity is very limited and key markers are consistent throughout the species. Sparrows will not find bluebirds hatching out of sparrow eggs nor will the next generation of coyotes have gills. (OK, that's very extreme, how about, sparrows will not likely develop into eagle, or even crow, sized birds.)

So both the 100,000 years claim, and the implied genetic stagnation, are exaggerations of the various study results. The studies have established very solid evidence for consistent genetic transfer across many generations and do establish that for every species, including humans, there really is an, "Eve," a common female ancestor that is both genetically compatible and "modern."
 
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