In his fourth-floor lab at Harvard University, Michael Desai has created hundreds of identical worlds in order to watch evolution at work. Each of his meticulously controlled environments is home to a separate strain of baker’s yeast. Every 12 hours, Desai’s robot assistants pluck out the fastest-growing yeast in each world — selecting the fittest to live on — and discard the rest. Desai then monitors the strains as they evolve over the course of 500 generations. His experiment, which other scientists say is unprecedented in scale, seeks to gain insight into a question ( http://www.simonsfoundation.org/quanta/20140717-the-new-science-of-evolutionary-forecasting/ ) that has long bedeviled biologists: If we could start the world over again, would life evolve the same way ?
Many biologists argue that it would not, that chance mutations early in the evolutionary journey of a species will profoundly influence its fate. “If you replay the tape of life, you might have one initial mutation that takes you in a totally different direction,” Desai said, paraphrasing an idea first put forth by the biologist Stephen Jay Gould in the 1980s.
Desai’s yeast cells call this belief into question. According to results published in Science in June ( http://www.ncbi.nlm.nih.gov/pubmed/24970088 ), all of Desai’s yeast varieties arrived at roughly the same evolutionary endpoint (as measured by their ability to grow under specific lab conditions) regardless of which precise genetic path each strain took. It’s as if 100 New York City taxis agreed to take separate highways in a race to the Pacific Ocean, and 50 hours later they all converged at the Santa Monica pier.
http://www.wired.com/2014/10/evolution-paths-fitness/
(Score: 3, Informative) by Anonymous Coward on Saturday October 04 2014, @01:09PM
I'm not convinced that having the fastest growth rate really indicates that they're the fittest for survival.
Just look at our modern world. Areas like Africa, India, and Bangladesh have tremendously high population growth rates. Yet these places are, to put it politely, generally complete shitholes in which to live and survive.
The Western world, with its much lower population growth rate, is a significantly better place to live and survive. Energy isn't wasted shitting out tens of children per mother, many of whom will die early, and those who become adults will die relatively young.
Instead, in the West, energy and knowledge are used sensibly to ensure that a small number of children almost all live to become adults, and then survive well into old age.
It isn't just a matter of geography, either. Europe, North America, Australia, Japan and South Korea are vastly different ecosystems, in very different locations. It is all about the people.
The fact that so many of these third-worlders try to flood into places like Europe, North America and Australia should show that the Western way is the fittest.
Fitness is about making the most effective use of the resources that are available. Shitting out numerous children, with this leading to poverty, disease, and hunger, isn't a signal of fitness; it's a signal of a lack of fitness.
(Score: 4, Insightful) by helel on Saturday October 04 2014, @02:46PM
If only the fastest survive and all the rest die then, by definition, they are the fittest. Think of it like chickens. Tastiness is an incredible fitness trait when it makes you one of the most populous birds on the planet.
Republican Patriotism [youtube.com]
(Score: 3, Insightful) by Anonymous Coward on Saturday October 04 2014, @07:10PM
Even by that definition, the only reason many Africans and Indians are alive today is because of Western innovations in massive-scale commercial agriculture, combined with billions of dollars in financial assistance provided to African nations and India by Western nations.
I don't consider one to be "fit" if his or her survival is wholly dependent upon others in such a manner.
(Score: 2, Informative) by Anonymous Coward on Saturday October 04 2014, @05:31PM
I'm not convinced that having the fastest growth rate really indicates that they're the fittest for survival.
Stop saying "survival of the fittest". The point of evolution is survival of the most adaptable species and the extinction of ones that cannot adapt to the changes. It's survival of the fittest to the environmental conditions, not survival of the fittest in modern colloquium. It has nothing to do with "fastest" or "strongest" or "best looking" or "sharpest teeth". It is always which life survives in a given environment when said environment changes.
Fitness is about making the most effective use of the resources that are available
You are wrong on many many levels here. See above. And your examples are wrong too. By almost all measures, people in India are much more efficient with their use of resources than people in the "West". Look up energy usage per capita in India vs. USA. In either case, that has nothing to do with anything. Human race is above evolutionary pressures, at least for now. That's why human population is increasing and will continue to increase until people become busy with other things (like in the "West") or carrying capacity is surpassed and disease and starvation does the job instead. But in either case, this has little to do with the process of Evolution.
(Score: 3, Insightful) by HiThere on Saturday October 04 2014, @06:43PM
The human race is neither "above evolutionary pressures" (whatever that means) nor isolated from them. We have actually been evolving quite rapidly for such a large animal with such a slow reproductive cycle.
The only sense that you could possibly be correct is that since we have created rapid transportation, we have been merging into a single gene-pool, but I'm not convinced that's really happening, and even if it were this still wouldn't isolate us from evolutionary pressures. What you might mean is that our current evolutionary pressures are quite different from those of our ancestors of 10 generations ago. That's probably correct, but changed pressures isn't at all the same as absence of pressure.
It is quite plausible that on a few decades genetic engineering will become common enough that you could reasonably claim that we have isolated ourselves from evolutionary pressures. I would still be dubious, but in that situation there would be reasonable grounds for the claim, and a need to take it seriously. But whenever there is differential survival in a population that isn't due to random chance there are evolutionary pressures....unless the descendants don't reflect their ancestors (which is why genetic engineering might make an arguable difference).
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 1, Informative) by Anonymous Coward on Saturday October 04 2014, @08:31PM
The races are negroid, caucasoid, mongoloid, and australoid.
Human is a species.
On top of this, race is a pseudoscientific thing.
Though Abel and Baker may appear to be of the same race, Abel's genome could easily be closer to Charlie's--even though Charlie appears to be of a different race than Abel and Baker.
-- gewg_
(Score: 1) by art guerrilla on Sunday October 05 2014, @12:57PM
thank you...
some poodles think their shit don't stink, and make a point of putting down the mixed cur dogs,
but we are all the same dog, dog...
some dogs have curly hair, some dogs do not;
some dogs have darker coats, some dogs lighter;
some dogs have larger phenotypes, some smaller;
but we are all the same dog, dog...
(Score: 1, Interesting) by Anonymous Coward on Saturday October 04 2014, @08:29PM
...you only have to be good enough.
As long as you live long enough to produce another generation of viable offspring, you have been successful genetically.
Yes, people have to stop repeating this "fittest" crap.
FTFS: selecting the fittest to live on
This reminds me of the original "Cosmos", where Sagan showed the crabs that got thrown back into the sea because their shells were thought to look like the face of a samurai.
The more a human perceived you to resemble a warrior, the greater chance you would not get eaten by a human that week.
The criterion were completely artificial and outside what would normally drive their evolution.
-- gewg_
(Score: 2) by sjames on Sunday October 05 2014, @04:39AM
Within the 'world' provided by the experiment, it was the one and only criterion of fitness and so that's what they adapted for.
As for the real world, we have to also consider that outside influences have changed the 'rules' in Africa in very short order from the standpoint of evolution and social change. We have the same basic genome in the West, but conditions are such that we naturally have less children. Make those conditions true of Africa and the same will happen there.
(Score: 3) by maxwell demon on Saturday October 04 2014, @01:14PM
To make an analogy: They made a simple air expansion experiment, found that the air expands the same way twice, and conclude that the weather would result in the same way.
Yes, the expansion of a gas is highly predictable despite the movement of individual atoms not being very predictable over the long time. But that does not mean that it is completely predictable in all situations.
And anyway, even if you could with 100% reliability predict how evolution reacts to environmental factors, if we started over, those environmental factors would certainly differ. To make an extreme example: What is the probability that a dinosaur-killing comet would again hit at the equivalent point in time?
The Tao of math: The numbers you can count are not the real numbers.
(Score: 1, Insightful) by Anonymous Coward on Saturday October 04 2014, @01:32PM
Well, let's think this through. The earth is 4.9 billion years old. Dinosaurs were around for 1.3 billion of those years. Astronomers today have cataloged over 740 million objects larger than a house within our solar system alone that could potentially collide with earth and produce an extinction-type event.
Pardon my notation (SN _needs_ to support MathML!), but if we do the stats here, we find that: d[E(1,300,000,000; 740,000,000) / (1,300,000,000 * 740,000,000)]/dX * d[740,000,000/1,300,000,000]dY = 0.641. So that's about a 1 in 3 chance of it happening again.
(Score: 2) by maxwell demon on Saturday October 04 2014, @04:08PM
The meteorite striking at the beginning of the dinosaur era would have had a very different effect on evolution than the meteorite striking at the time it did.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 4, Interesting) by bzipitidoo on Saturday October 04 2014, @01:29PM
The analogy of a drive to anywhere on the Pacific coast isn't the best. A better analogy is hill climbing. Life is trying to optimize, that's the idea of survival of the fittest. Start anywhere on the same hill and "hill climb". You don't have to know which way to go, all you have to do is move higher. Everyone will arrive at the same top, even if they wander a little and don't take the most direct route, find the steepest climb. It's a common operation in computational geometry. Compute the gradient, then step upwards-- or downwards if you're looking for a minimum instead of a maximum.
Sounds more likely that the experiment as performed explored a small area that didn't have more than one hill.
(Score: 0) by Anonymous Coward on Saturday October 04 2014, @01:36PM
If this is true, then why has most of Africa always been stuck in a valley, even before Europeans ever visited? Why have people in pretty much every other area of the world, from ancient Mesopotamia to ancient Mesoamerica to ancient China through to modern Europe, Japan and North America, been able to achieve civilization at some point, while all of Africa aside from ancient Egypt has not managed this?
(Score: 0) by Anonymous Coward on Saturday October 04 2014, @02:00PM
One possible reason could be conservatism. No, not political, but "This is how we've always done things!" traditionalism and similar. Just as cities built today will be superior to towns built 200 years ago, and the towns from 200 years ago are basically still exactly the same now as they were then; so long as the elders of the African Tribes were still alive, holding on to the old traditions, there would be significant resistance to change things, such as switching the tribes from nomadic to sedentary lifestyles.
(Score: 2, Interesting) by UncleSlacky on Saturday October 04 2014, @05:23PM
Clearly you've never heard of Great Zimbabwe:
https://en.wikipedia.org/wiki/Great_Zimbabwe [wikipedia.org]
(Score: 0) by Anonymous Coward on Saturday October 04 2014, @07:18PM
It's not really worthy of consideration. In fact, it actually supports what the GP was saying. Great Zimbabwe is not at all remarkable. It's pretty basic brickwork by any standard, especially for being built between 1000 A.D. and 1300 A.D.
It's nothing compared to the great cathedrals that Europeans were building at the time. It's nothing compared to what the Romans had built a thousand years earlier. It's nothing compared to what various Middle Eastern, Central American and Southern American civilizations had been building at the same time, or had built some time earlier. It's nothing compared to what ancient Chinese dynasties had achieved.
Sorry, it just isn't impressive at all. It's somewhat disappointing that that's all that could be achieved.
(Score: 4, Informative) by HiThere on Saturday October 04 2014, @06:53PM
One reason is the tse-tse fly.
Seriously, think of humans as an invasive species. When they leave the area in which they've evolved, they leave behind the predators that have evolved together with them. Bears are dangerous, but they don't compare with leopards, when all you've got is a thrusting spear.
Then there's sleeping sickness, malaria, Ebola, etc. There are good reasons why Africa used to be called "the white man's graveyard" and they don't have much to do with the human inhabitants. It wasn't only the graveyard of white men, but the natives didn't get the same press.
That said, there's reasonable evidence that Africa is one of the places that discovered refining iron. So to claim that they've always been stuck in a valley is unfair. For that matter, Egypt is one of the ancestral civilizations. And Ethiopia was a strong enough country to keep them from expanding to the south (or we'd have had coffee a lot earlier).
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 3, Insightful) by Immerman on Saturday October 04 2014, @05:36PM
That assumes you start high enough on the hill that it has only a single peak above you. Try doing the same thing starting at the bottom of a mountain range and you'll find there's an awful lot of different peaks above you.
As far as the yeast in this case is concerned there's only one peak, because they are being artificially selected for only one trait (speed of reproduction), so convergent evolution is almost inevitable. Out in the real world though we have these things called "ecological niches" wherein various unrelated species are continuously influencing each other's development through competition and collaboration. Once you've got a chaotic system in play you increase the number of local maximums dramatically and convergence becomes the exception rather than th norm.
(Score: 2) by Non Sequor on Saturday October 04 2014, @07:56PM
The phenomenon of convergent evolution indicates that the shape of the terrain is dictated by the requirements of ecological niches with the preexisting gene pool being less important.
If you reran life on earth again, an awful lot of things would end up having analogous traits to what we have now because given sufficient time the same ecological niches would develop. Developmental biology would be different because evolutionary arms races might take place in a slightly different order and the organisms that get shoehorned into a particular niche might be different.
Write your congressman. Tell him he sucks.
(Score: 3, Funny) by ticho on Saturday October 04 2014, @01:38PM
I wonder, does this experiment take into account butterflies flapping their wings?
(Score: 0) by Anonymous Coward on Saturday October 04 2014, @01:56PM
project mkultra
project monarch
(Score: 4, Insightful) by Dunbal on Saturday October 04 2014, @02:18PM
Absolutely not. Not only would geography and random catastrophic events play a part in deciding which genes got to move forward and which ones didn't, but the evolution of other species can and would affect the evolution of your species.
(Score: 2) by SlimmPickens on Saturday October 04 2014, @07:50PM
The single biggest agent for change was the introduction of high levels of oxygen to the atmosphere. The proteins and enzymes that stick cells together pre-existed multicellular by perhaps billions of years (as tools for eating other bacteria etc) but those reactions are very energy intensive and simply weren't feasible on a large scale until there was plenty of oxygen in the atmosphere. There's not really a lot of bacteria nowadays that do not depend on oxygen.
Learned this from Neil Shubin's excellent book, Your Inner Fish.