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Observing Evolution Over 40,000 Generations
Last year we discussed the work of Richard Lenski, who has been breeding E. coli for 21 years in a laboratory in Michigan. Then, the news was that Lenski's lab had caught direct, reproducible evidence of a genetic mutation with functional consequences for an organism. Now Lenski's lab has published in Nature a major study comparing adaptive and random genetic changes in 40,000 generations of E. coli (abstract here). "Early changes in the bacteria appeared to be largely adaptive, helping them be more successful in their environment. 'The genome was evolving along at a surprisingly constant rate, even as the adaptation of the bacteria slowed down,' [Lenski] noted. 'But then suddenly the mutation rate jumped way up, and a new dynamic relationship was established.' By generation 20,000, for example, the group found that some 45 genetic mutations had occurred, but 6,000 generations later a genetic mutation in the metabolism arose and sparked a rapid increase in the number of mutations so that by generation 40,000, some 653 mutations had occurred. Unlike the earlier changes, many of these later mutations appeared to be more random and neutral. The long-awaited findings show that calculating rates and types of evolutionary change may be even more difficult to do without a rich data set."
Sorry, the buffalo comment was not necessary - but was in the slashdot tradition and just as wild as the other comments directed towards us creationists around it.
The fact remains that after 40,000 generations, what the scientist has is a marginally more efficient strain of E. coli than he started with. He can track all the mutations to see how it has changed. He can see how and when those changes occurred - which is indeed fascinating, but at the end, he still has an E. coli. His very statements were that the later changes were not as drastic as the first which leads away from an evolution argument.
If he is making other claims, then the linked abstracts don't make that clear.
I'd say it was a great study in the work of natural selection, but a weak study in evolution until it crosses the border into some other definitely recognizable bacteria. High school biology was a long time ago - I let my wife handle the micro-biology today - she has a degree in it.
But you do extend logic past the empirical evidence which is the same as making shit up.
This E.coli experiment does nothing to show speciation or anything other then evolution on a micro-scale is possible. But hell, we have known that for centuries.
How you can jump and fault someone over a belief in god because of this is just inane. There is no logic behind it and you have made the first part of your post out to be false.
Not true. You are posing the missing link myth. There are in fact good lines of fossils showing evolutionary trends in species for many different species in the fossil record.
Indeed, the fossil records show a definite trend dating back to the earliest records we have of life, but we only have slices of the tree. Surely we should have fossils from two concurrent species. If not that, shouldn't we have fossils from a species whose ancestors are alive today?
While no we do not and never will have a direct individual by individual line of fossils simply because most creatures that lived on this earth were eaten, rotted and NOT fossilized. Fossilization also did not occur uniformly through all species or stages of evolution, it was collection of many random processes, and thus one would expect gaps in the fossil record. Also most fossils on earth have not been dug up and analyzed by scientists, we only have a small fraction of the record out there and already we can see clear patterns of what is loosely called evolutionary trends.
Right. However, evolution has never stopped. It took 65 million years to get from the first mammals to every living mammal live today. While 65,000,000 years is a really long time, it still seems like a fairly short time when you consider that every living mammal today should be traced back to a single Tertiary rodent, each step of the way having only two parents. The only way for that to happen is if evolution is fairly rapid. That kind of change should be noticeable in at least a recent fossil record. We've found whole carcasses of mammoths and many other creatures dating as far back 10000 years ago. Shouldn't one of those be evolutionarily successful enough to have offspring alive today? They all seem to be cousins of whatever creature evolved.
Also just because one species "evolves" from another doesn't mean that the so-called "parent" species stops evolving.
Exactly! It's likely that a "parent" species would branch to several different species. My question is, "Why do we only find the branches? Why have not found a single spot where these branches meet?"
If you really want an example of diverging species look at the Great Dane and Chihuahua or nearly any other domestic species, such as the cow, that has shown great variations between breeds. In the former example mating is nearly impossible. Don't like that? What about Horses/Donkeys? No we don't have records old enough to historically prove it, but the evidence is there.
No, but a great dane and chihuahua can breed (hope the chihuahua pitches!) and should share a "normal" sized ancestor somewhere up the chain, but it's still a dog. And why are there no "near" dogs that evolved from dogs, but are just out of special reach? Why has the K9 branch of the evolutionary tree not branched? A better example may have been cats since a Lion and Tiger can't breed (as far as I know). But still, the now extinct Liger hasn't been found.
And horses and donkeys can breed. That's where mules come from. While it is an excellent example, a common ancestor between the two should have not died off that long ago (in thousands of years). That "honkey's" fossils wouldn't be that old and should be much easier to find than that of Sue, for example. Where is that "honkey"?
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
Mammals formed in the Tertiary period, about 65 million years ago.
Your statement is inconsistent with the earth only being 6000 (was it 12000?) years old. Enjoy your time in hell.
Insanity: voting in the same two parties over and over again and expecting different results
The "0%" is a lie, or a willful lack of knowledge. There are many transitional fossils that have been discovered, including dozens of specimens that illustrate the progress of humankind as a species. Only the American Taliban seriously regard the evolutionary theory as anything but well-founded science.
I never said it wasn't "well founded science", but it is certainly not complete. For that matter it never will be complete as time has wiped out much of the data.
Now, I've already said that the fossil record shows a definite progression, "trend" was the word used, but every fossil found has been a relative of a modern species. No kidding, EVERY LIVING AND EXTINCT SPECIES IS A RELATIVE!!! Show me a DIRECT special ancestor between two different species, not a cousin of that direct ancestor.
So by the fact that I'm asking should prove that this is not a "willful lack of knowledge" and the fact that you can't provide me with an answer proves it not a lie, at least not on MY part.
Oh, and I wouldn't throw around the "taliban" quote around so lightly... well, unless someone in America has banned your wife/mother/daughter from doing things like driving, leaving the house without a man, going to school and so on. Using the Taliban in that way is a merely a slight variation of Godwin's law and really just shows a bigotry and ignorance from you that evangelists can only dream of.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
Turkey has more evolution unbelievers than the states... but other polled countries have less with America being the 2nd stupidest by this metric of 33 other countries.
(insert usual stuff about sample sizes, polling methods, etc etc)
The revolution will not be televised... but it will have a page on Wikipedia
...Why do we only find the dead end?...
Maybe because the evolution of a rodent into a pachyderm is dead wrong? The word evolution as applied to the adaptability of living organisms is what the article is all about. After 40,000 generations, the organism was still in E. coli and nothing else. All dogs have a common ancestor, but that was still a dog, nothing else. Thousands of generations of fruit flies have been bred, with many variations and mutations, but all are still essentially fruit flies.
All theory is gray