PDA

View Full Version : Frog in amber may be 25M years old



Abbey
02-17-2007, 01:52 PM
To my untrained eye, this frog certainly looks a lot like present-day tree frogs.
Which makes one wonder- after 25 million years, shouldn't this species have evolved some?

Frog in amber may be 25M years old Fri Feb 16, 5:43 PM ET

MEXICO CITY - A miner in the state of Chiapas found a tiny tree frog that has been preserved in amber for 25 million years, a researcher said. If authenticated, the preserved frog would be the first of its kind found in Mexico, according to David Grimaldi, a biologist and curator at the American Museum of Natural History, who was not involved in the find.

The chunk of amber containing the frog, less than half an inch long, was uncovered by a miner in Mexico's southern Chiapas state in 2005 and was bought by a private collector, who lent it to scientists for study.

A few other preserved frogs have been found in chunks of amber — a stone formed by ancient tree sap — mostly in the Dominican Republic. Like those, the frog found in Chiapas appears to be of the genus Craugastor, whose descendants still inhabit the region, said biologist Gerardo Carbot of the Chiapas Natural History and Ecology Institute. Carbot announced the discovery this week.

The scientist said the frog lived about 25 million years ago, based on the geological strata where the amber was found.

Carbot would like to extract a sample from the frog's remains in hopes of finding DNA that could identify the particular species, but doubts the owner would let him drill into the stone. "I don't think he will allow it, because it's a very rare, unique piece," said Carbot.

Grimaldi of the American Museum of Natural History called the idea of extracting DNA "highly, highly unlikely," given that — as other scientists have noted — genetic material tends to break down over time.

But George O. Poinar, an entomologist at Oregon State University who founded the Amber Institute, said extracting DNA is theoretically possible.

"If it's well-preserved ... and none of the frog has been exposed to the outside, where air could enter in and oxidize the DNA, it could be possible to get DNA."

http://news.yahoo.com/s/ap/20070216/ap_on_sc/mexico_frog_in_amber

jillian
02-17-2007, 01:59 PM
Abbey,

Not all animals change that much. If they're well-suited to their environments, then there's no reason for them to change and it's more likely that genetic mutations wouldn't survive.

Crocodiles, certain sharks and some insects also haven't changed much, although there's been some change in size.

Horseshoe crabs are pretty much as they were, too.

Isn't an argument against evolution. :beer:

Missileman
02-17-2007, 02:08 PM
To my untrained eye, this frog certainly looks a lot like present-day tree frogs.
Which makes one wonder- after 25 million years, shouldn't this species have evolved some?

I guess that depends on what the driving force behind evolution is. I've always considered necessity to be the primary cause. A successful organism that's found its niche would not need to evolve further until something upsets the balance.

manu1959
02-17-2007, 02:11 PM
human beings are not evolving

Gunny
02-17-2007, 02:12 PM
I guess that depends on what the driving force behind evolution is. I've always considered necessity to be the primary cause. A successful organism that's found its niche would not need to evolve further until something upsets the balance.

Seems to me if a life form could not survive in its environment, it'd be kind of hard for the dead to evolve into something that could survive.

manu1959
02-17-2007, 02:13 PM
Seems to me if a life form could not survive in its environment, it'd be kind of hard for the dead to evolve into something that could survive.

that is how it happens the dead ones are the week ones the live ones reproduce....problem is welfare etc....lets the weak ones live

Missileman
02-17-2007, 02:24 PM
Seems to me if a life form could not survive in its environment, it'd be kind of hard for the dead to evolve into something that could survive.

Which is why catastrophic changes have led to mass extinctions in the past. A gradual change in a niche would more likely lead to a gradual adaptation in the organism. It's still born of necessity.

jillian
02-17-2007, 02:32 PM
that is how it happens the dead ones are the week ones the live ones reproduce....problem is welfare etc....lets the weak ones live

True of things like IVF and AI, as well, no?

manu1959
02-17-2007, 02:39 PM
True of things like IVF and AI, as well, no?

sure....as do doctors, medicine, indoor plumbing, grocery stores, cars, clothes, you name it.......

but i could argue the rich can afford these things more so than the poor so natural selection would be a function of the ability to earn money and benifits....which is the modern day equal of hunting and gathering....

manu1959
02-17-2007, 02:41 PM
Which is why catastrophic changes have led to mass extinctions in the past. A gradual change in a niche would more likely lead to a gradual adaptation in the organism. It's still born of necessity.

to be more specific, mass extinction of a particular species....not life itself.....correct?

darin
02-17-2007, 02:51 PM
I wish we could evolve solely based on our percieved NEED. If that did happen, I'd start shitting money.

jillian
02-17-2007, 02:53 PM
sure....as do doctors, medicine, indoor plumbing, grocery stores, cars, clothes, you name it.......

but i could argue the rich can afford these things more so than the poor so natural selection would be a function of the ability to earn money and benifits....which is the modern day equal of hunting and gathering....

That's an interesting perspective. But by the same token, there's a correlation between number of children and low socioeconomic status, so kind of mitigates the other way.

manu1959
02-17-2007, 02:54 PM
I wish we could evolve solely based on our percieved NEED. If that did happen, I'd start shitting money.

not sure that is where i would want money to be coming out of my body

darin
02-17-2007, 02:57 PM
not sure that is where i would want money to be coming out of my body

If it were coin, rolled and wrapped...it'd be aight. Especially the Susan B Anthony dollars.

manu1959
02-17-2007, 02:59 PM
That's an interesting perspective. But by the same token, there's a correlation between number of children and low socioeconomic status, so kind of mitigates the other way.

there is economic incentive to have lots of children when you are poor....one you have a lot more little workers you can send out to beg borrow or steal and the govt. pays you more to have kids.........plus since you are poor you are probaly not too bright since you don't have a job and have more kids than you can afford to feed....or you are nuts....or sick....but none the less the govt. keeps you alive......pays you to have more kids....which allows the weak to produce more offspring....societly social programs ensure survival of the weakest....

Missileman
02-17-2007, 03:04 PM
to be more specific, mass extinction of a particular species....not life itself.....correct?

Or multiple species...I'd even say that life itself could be threatened by certain events.