Evolution can occur quickly and change how populations interact [Lab demonstration]

Cornell University ^ | 03 July 2006 | Susan Lang

[PatrickHenry]

Biologists generally accept that evolutionary change can take from decades to millennia, while ecological change can occur over mere days or seasons. However, a new Cornell study shows that evolution and ecology can operate on the same time scale.

When evolution occurs so quickly, the researchers conclude, it can change how populations of various species interact. Ecologists need to consider such evolutionary dynamics in their studies because evolution could affect populations being studied. This insight is critical to predicting the recovery time needed for threatened populations or for predicting disease dynamics, says Justin Meyer '04, who conducted the study as an undergraduate student with Cornell ecologists Stephen Ellner, Nelson Hairston and colleagues.

To observe ecological and evolutionary changes together, the researchers monitored the ecological fluctuations in a model predator-prey laboratory system: a microscopic organism called a rotifer that eats a single-celled algae.

Meyer developed a method to track genetic changes, and the researchers found that as the prey population fluctuated, the algae "evolved" from a type that grows quickly to a type that resists being eaten. The frequency of the algal-genotype changes in response to rotifer population flux clearly demonstrated the synchronicity of ecological and evolutionary time.

The study is published in the July 11 issue of Proceedings of the National Academy of Sciences.

[Oztrich Boy]

If mutations are not responsible for population diversity, and if everything is descended from two of its kind, one male, one female, that rode on Noah's Ark, then where did all the population diversity come from?

A wizard cast a spell

[donh]

How, exactly does algae resist being eaten, I wonder...

Attitude.

[SaveUS]

That pigeon on the bottom is obviously a White Noser. I wonder if all the other pigeons talk about him behind his back like the humans do about their Brown Nosers.

[DungeonMaster]

Evolution can occur quickly and change how populations interact [Lab demonstration]

Thought it was a done deal based on this title. The title sure doesn't imply any of the stuff you stated about process.

[Elsie]

To observe ecological and evolutionary changes together, the researchers monitored the ecological fluctuations in a model predator-prey laboratory system: a microscopic organism called a rotifer that eats a single-celled algae.

Meyer developed a method to track genetic changes, and the researchers found that as the prey population fluctuated, the algae "evolved" from a type that grows quickly to a type that resists being eaten. The frequency of the algal-genotype changes in response to rotifer population flux clearly demonstrated the synchronicity of ecological and evolutionary time.

 

A MODEL???

 

Why the quotes???

 

Huh?

[Elsie]

Congratulations to all the trolls who helped to make this move possible.

And a big

Thank You!

for posting it in the first place!

[Elsie]

I have often said that man has interfered with his own evolution with the implication that he better be successful in engineering a better human or he will get extinct pronto.

Merely interfer?!?

He has tried to STOP it completely!

Why... them birth 'defects' may REALLY be advantages later on; and them early deaths from disease may be Natures way of culling the ones who weaken the Specie!

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Why do the E believers try to 'correct' the First and 'delay' the Second?

[Elsie]

We have had a lot of threads dumped into Chat or the SBR because of deliberate trolling.

Boo hoo!

How does we KNOW it was 'deliberate'?

And does it REALLY matter what ROOM these threads are in?

We STILL get to read and post to them.

[SaveUS]

"How does we KNOW it was 'deliberate'?"

Elsie, in your case I'm sure it isn't deliberate. I really don't think you have a clue what thread you are in, and what you want to say. Do you ever have conversations with people, and they slowly back away, get the kids up, then turn and run real quick? That should be a signal.

[furball4paws]

Damn, Elsie.. I'm disappointed. Don't I deserve at least a few bible verses?

[LibertarianSchmoe]

You're right, DLR, that jabs are thrown even before the appearance of "The Other Side". A couple of my own observations regarding this phenomenon:

• "I think "bashing" is a bit of a mischaracterization. Although it does happen from time to time, most of us on both sides do NOT endorse or engage in genuinely hurtful "bashing". Most often, it is mildly sarcastic commentary. It really is. I believe that if you come into this forum with thin skin and/or a strongly defensive posture, EVERYTHING becomes an attack.

• Neither "Evos" nor "Creos" are the exclusive jabbers, even though some complain that it is so. For every Evo who believes that theistic belief is silly, there is a Creo who revels in the belief that such people will burn in Hell for all eternity.

Frankly, I find that these threads are most informative AND entertaining when BOTH sides are present.

[SunkenCiv]

Al G. sample:

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ready to fight 'em off.

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[PatrickHenry]

Placemarker.

[Sinner6]

It is in chat now. Are you compairing the mods to jesus? :P

[Elsie]

I really don't think you have a clue what thread you are in, and what you want to say.

Ok...

[Elsie]

Yes; you do.

[Lexinom]

You will agree there's only so far they can go. There is an archetypical form for the species. Otherwise the fossil record would be chock full of transitional forms. It is not.

That's why we're discussing the notion of evolution occurring quickly - after all, we know evolution is true, we just need to fit the facts to match the theory.

[CarolinaGuitarman]

"You will agree there's only so far they can go."

Why would one do that?

"There is an archetypical form for the species."

No there isn't.

"Otherwise the fossil record would be chock full of transitional forms. It is not."

Sure it is.

[PatrickHenry]

Of all species living today (ignoring bacteria and a few others like flatworms, sponges, horseshoe crabs and insects), sharks have probably been around the longest. There is evidence that modern sharks first appeared about 100 million years ago. Because virtually all other present-day species emerged later, it is highly likely -- perhaps even obvious -- that at least some of the extinct species which flourished before modern sharks were transitional -- that is, they were the ancestors of later species.

Side issue: Many species appearing more recently than sharks are also extinct. Like those which lived before, they too were either evolutionary dead-ends or transitional forms.

Therefore, all fossils of now-extinct species are either: (a) non-transitional dead-ends; (b) transitional, but leading to eventual dead-ends; or (c) transitional and leading to species now living.

Side issue: The same may be said of all currently-living individuals of every species: (a) some will die without reproducing; (b) others will produce offspring, of which some will eventually be barren; and (c) some will produce long, unbroken lines of offspring.

[CarolinaGuitarman]

Oh, BTW, you still haven't defended your silly claim that *pigeons* are one species.