Posted on 04/08/2016 8:45:34 AM PDT by JimSEA
The pace of evolution is typically measured in millions of years, as random, individual mutations accumulate over generations, but researchers at Cornell and Bar-Ilan Universities have uncovered a new mechanism for mutation in primates that is rapid, coordinated, and aggressive. The discovery raises questions about the accuracy of using the more typical mutation process as an estimate to date when two species diverged, as well as the extent to which this and related enzymes played a role in primate evolution.
Alon Keinan, associate professor of Biological Statistics and Computational Biology at Cornell, and Erez Levanon, co-senior author and an associate professor with the Mina and Everard Goodman Faculty of Life Sciences at Bar-Ilan University in Israel, describe the novel, and rare, process triggered by a member of the APOBEC family of virus-fighting enzymes in the journal Genome Research. As primates evolved--including chimpanzees, Neanderthals, and modern humans--the number of types of viruses tailored for targeting primates multiplied. APOBECs in our cells mount a vigorous defense, bombarding the viral genome with clusters of mutations to render them unable to continue an infection. However, having such a mutation-based defense is risky for cells, since "friendly fire" could wreak havoc on our genome as well. Indeed, the enzymes have been shown to cause mutations in the tumor cells of breast and other cancers.
(Excerpt) Read more at sciencedaily.com ...
“The discovery raises questions about the accuracy of using the more typical mutation process as an estimate to date when two species diverged.”
Oops... I’ve pointed out that this type of dating is completely unreliable, because when you extrapolate into the past with so many unknown variables, there is no way to confirm the accuracy of anything the method produces. Vindication tastes sweet :)
Evolution of a liberal to a conservative would be quick.
A) Release liberal into the real world
B) Liberal shocked at high price of everything including rent
C) Liberal votes for lower taxes
D) Liberal gets mugged
E) Liberal votes for more prison time for criminals
F) Liberal sees others using the street and their yard for a bathroom
G) Liberal votes for conservative issues
If anything, I would say that humans are devolving...
Good points.
I read an article recently by someone, who laments that many parts of San Francisco reek of urine. What has happened to this beautiful city, etc. Wrote this liberal writer. San Francisco has been so liberal on homeless issues that they are overrun with them. Which has led to critical numbers of people doing their bathroom functions everywhere in public.
I’ve always wondered if apes evolved into humans, why are there still apes? Evos give me some gobbeldy gook about how it’s random and not every ape’s DNA mutates. So basically evolution can’t be replicated in the lab—ergo it doesn’t comport to the scientific method. i.e. evolution is not scientific, it can never be more than a “theory” until they can replicate it in the lab.
Question is there a theory of evolution for cells?
in that in your body cells replicate and die off ...so is there a similar survival of the fittest mechanism?...
superior cells replicate inferior cells simply die off....
Do cells in the body even in anyway compete for resources?
And cells themselves don’t do any kind of genetic swapping ...in that two different cells don’t combine there genetic material to produce a third cell with hopefully the best elements of both parent cells
I’ve seen a number of articles in recent years, which discussed how Neanderthals interbred with humans , and that the interbreeding resulted in Neanderthals dying out. So you wonder if modern humans are the result of interbreeding among many primate species. But then, did we see survival of the fittest among the strains if early man?
You've said nothing that wasn't reported by the scientists themselves.
From the beginning, efforts to calculate average long-term genetic mutation rates were acknowledged as fraught with problems.
Similar problems are found in, for example, carbon-14 dating, where it's possible to compare a calculated carbon-14 date versus a known-for-certain date of some ancient material (i.e., tree rings).
Such careful measurements have produced various charts which are used for what they call "wiggle matching".
Wiggle matching charts convert carbon-14 derived dates to a nearby actual known date.
So far, "wiggle matching" of DNA mutation rates to actual known rates has not been possible.
But recent analyses of ancient DNA in, for example, Neanderthals, makes such charts possible in the future.
“You’ve said nothing that wasn’t reported by the scientists themselves.”
Perhaps it was acknowledged by responsible scientists, but it certainly was NOT acknowledged by the popular advocates of evolution. You will never see them acknowledge the problems or weaknesses of the methods they use to support their pet hypothesis.
Most of our evolution nowadays isn’t genetic, but social, and yes, I would say socially we are devolving.
The survival of the organism is selected for, the cells have their “instructions” from the organism’s DNA. Each individual cell doesn’t go off on its own except perhaps you can look at cancer cells as something approaching that.
Survival of the fittest references the organism as a whole. The “instructions” for individual cells are where mutations generally occur. It’s more accurate to reference “survival of the fit” as no path to perfection exists, just survival.
Nothing in evolution demands any sort of perfection, just survival and ability to propagate. Perfection is normative.
It doesn’t work that way. We have dogs who evolved from wolves but we still have wolves. Humans and apes share a common ancestor. Of course there are both apes and humans as both branches of the primate family are still around.
The inbreeding per se had nothing to do with the extinction of Neanderthals. Humans may have out competed Neanderthals for scarce resources with the loser going extinct. We have seen that many species related to modern humans have gone extinct for many reasons, often related to change of environment where they could no longer find enough food. We have continued to exist in large measure because of our adaptability to different environments from desert to forest to plains to Artic.
While species may show adaptations over time, there is nothing to support the notion that any species has ever diverged into another species.
I've always wondered why people ask such a question, when the answer seems so obvious: by analogy, if Brits "evolved" into Americans, why are there still Brits?
The obvious answer is because Americans are here, and Brits are still there.
Likewise, some apes are still doing today what they were doing many years ago.
But, of course, apes did evolve also, from our common ancestors of, say, 8-million years ago.
But each ape (orangutans, gorillas, chimps) evolved for their own particular environments, whereas humans somehow evolved to survive in virtually all environments.
Auntie Dem: "Evos give me some gobbeldy gook about how it’s random and not every ape’s DNA mutates."
I find that anti-evos love, love to distort & misrepresent actual evolution theory, such as you do here.
In fact, "random" is not the issue, nor is a faster or slower rate of DNA mutations.
No, the real issue here is separations of one population from others, and the resulting adaptations which are not then shared amongst all.
If the separations remain long enough in time, and the adaptations (= evolution) become major enough, then those separated populations will no longer be able to interbreed, and so by definition are now separate species.
Auntie Dem: "So basically evolution can’t be replicated in the lab—ergo it doesn’t comport to the scientific method. i.e. evolution is not scientific, it can never be more than a “theory” until they can replicate it in the lab."
FRiend, we're dealing here with three categories of scientific idea: 1) hypothesis, 2) theory, 3) fact.
Let's start with facts: a fact is a scientifically confirmed observation -- if you can see it, and understand it, then it's a fact.
A theory is a confirmed explanation of facts.
Theories are "reasons why" of observed facts.
By definition, a theory is not a fact, but strongly confirmed theories are nearly as certain as facts.
For examples, think of any number of scientific theories which nobody seriously challenges today.
Sure, any of them might be falsified someday, but so far as we know, they are as good as facts, and we use them to build all kinds of machines on which our lives depend.
Among those strongly-confirmed theories is basic evolution: 1) descent with modifications & 2) natural selection among separated populations leading to long-term speciation.
Today, every element of evolution is either observed fact of strongly confirmed theory.
The third category is hypothesis = unconfirmed testable idea.
Popular science articles often mistake hypotheses for theories.
Today, the word "hypothesis" covers some of various scientific ideas relating to origins of life on earth.
“You will never see them acknowledge the problems or weaknesses of the methods they use to support their pet hypothesis.”
If that were true, we’d be stuck with what Darwin wrote. The theory of evolution is constantly changing in detail but the core theory has never been disproven. It has been fleshed out tremendously and continues to be.
The answer is pretty simple: not those apes.
And there’s lots of science that can’t be replicated in the lab. Generally because of scale, either the stuff is too big or the time line is too long. Technically speaking we COULD replicate evolution in the lab, it would just have to be a lab that was self contained for a couple tens of thousands of years. It doesn’t make them not science, it just means there’s a whole other section to the scientific method that nobody ever bothers to learn in high school.
I agree that popular science articles often blur important distinctions between fact, theory and hypothesis.
Particularly annoying to me: they also like to call ancient creatures "human" when in reality those were just distantly related hominids.
As for average DNA mutation rates, those are relatively easy to calculate, but near impossible to confirm.
Indeed, such data-points as we do confirm for long-term mutation rates often contradict other data-points from other sources.
So the significance of this particular article is that it provides a possible explanation for why mutation rates seem so unpredictable.
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