'Explosive' evolution in pupfish

Apr 27, 2011
This is a typical, detritus-eating pupfish from San Salvador Island. Credit: Chris Martin, UC Davis

Two groups of small fish, one from a Caribbean island and one from the Yucatan peninsula of Mexico, exhibit some of the fastest rates of evolution known in any organism, according to a new UC Davis study.

About 50 species of pupfish are found from Massachusetts to Venezuela -- and they are all pretty much the same, said lead study author Chris Martin, a UC Davis graduate student working with Peter Wainwright, a professor of and ecology at UC Davis.

"They look the same and they act the same," eating detritus and algae off rocks, Martin said.

Except in two places. In shallow, salty lakes on San Salvador island in the Bahamas, Martin found that one of the three pupfish species present lives by biting the scales off other , while another eats small and clam shrimp.

No other pupfish is known to eat scales, Martin said.

Among pupfish originally from the Yucatan area, one eats other fish and another feeds on . Sadly, these fish are now extinct in the wild and only found in labs and aquaria.

The pupfish evolved changes to their jaws to match their specialized diet, allowing Martin to construct an evolutionary map for the species.

This pupfish from San Salvador island is the only species known to eat scales from other fish. Credit: Chris Martin, UC Davis.

If the evolution of all pupfish is like a steadily expanding cloud, Martin found that the San Salvador Island and Yucatan pupfish are like bursts of fireworks within it. They show explosive rates of evolution – changing up to 130 times faster than other pupfish, he said.

It's not clear why the pupfish in the two locations are evolving so fast. In both places, the lake water is hot and salty – but that's true in other places where pupfish live. And mosquito fish, found in the same two lakes, show no signs of rapid change.

Martin is continuing his research by taking lab-bred fish, including hybrids, back to the lakes to see whether they thrive. He hopes to see which fish succeed out of a spectrum of hybrids.

The research is published online in the journal Evolution. Martin is a National Science Foundation graduate research fellow.

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Provided by University of California - Davis

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gmurphy
5 / 5 (3) Apr 27, 2011
Evolution thrives on opportunity. I would opine that if evolution has accelerated it is because the resources available for the phenotypes to exploit within their particular ecological niche have diversified or changed significantly
kevinrtrs
1 / 5 (10) Apr 28, 2011
So when can we expect the pupfish to sprout wings and fly in the water? or to develop feet and air-breathing lungs to climb out and walk on the land? Or to grow super large and turn into whales? Isn't this what EVOLUTION is supposed to mean - that from one organism one can get multiple others, not more pupfish as in this case?
I hope the evolution observed here accelerates to such an extend that we can actually observe some new creatures emerging from this population. That would be incredibly exciting.
Skeptic_Heretic
5 / 5 (3) Apr 28, 2011
So when can we expect the pupfish to sprout wings and fly in the water? or to develop feet and air-breathing lungs to climb out and walk on the land? Or to grow super large and turn into whales? Isn't this what EVOLUTION is supposed to mean
No. Evolution is the non-random survival of randomly generated organisms. If there is a niche to be inhabited, evolution will favor randomly generated organisms (offspring) based on their suitability to that niche.
J-n
5 / 5 (3) Apr 28, 2011
So when can we expect the pupfish to sprout wings and fly in the water? or to develop feet and air-breathing lungs to climb out and walk on the land? Or to grow super large and turn into whales?

What bennifits would those mutations provide? Why would a flying pupfish survive longer or breed better? same for an air breathing, walking pupfish? or a super large pupfish?

Not sure why i'm feedin' the trolls but.. hey.. makes the day go by quicker..
GSwift7
5 / 5 (4) Apr 28, 2011
So when can we expect the pupfish to sprout wings and fly in the water? or to develop feet and air-breathing lungs to climb out and walk on the land?


My best guess would be about 0.8342 million years +/- .001 million years. (joke of course)

Would it be so hard to accept that a God could create a world based on science where His creations are able to adapt and change over time? I say it is entirely possible that that's the case, because it looks like that is the world we live in. So, if God created it all, then it appears that He created a world in which evolution occurs.

On the other hand, maybe He just made it look that way and it's an illusion to play with our minds.
Donutz
5 / 5 (4) Apr 28, 2011
So when can we expect the pupfish to sprout wings and fly in the water?


@kevinrts

So when can we expect you to produce some evidence in support of your magical sky fairy? Maybe an explanation for why there's no evidence of the global flood or the wandering in the desert? Maybe a rationalization for all the errors in your inerrant book of fables? That's ok, I'll wait...
J-n
5 / 5 (2) Apr 28, 2011
Personally if i had the chance to get answers from a 'True Christian' one who believes the literal translation of the bible, i'd definetly ask about much more than proof of their God.

I'd ask about
Leviticus 25:44-46
Luke 12:47-48
Ephesians 6:5
Exodus 21:20-21
Exodus 21:2-11

Just to start.
thales
5 / 5 (3) May 03, 2011
I'd ask about
Leviticus 25:44-46
Luke 12:47-48
Ephesians 6:5
Exodus 21:20-21
Exodus 21:2-11

Just to start.


You'd be more likely to convince them that slavery is okay than that the Bible is wrong.
DavidMcC
5 / 5 (2) May 06, 2011

You'd be more likely to convince them that slavery is okay than that the Bible is wrong.

Especially as it hasn't always been considered "unchristian" to trade in slaves. Otherwise the British empire would have had to deal fairly with captured Africans.