Genetic Changes In Mice 'Question Evolution Speed'

Ananova ^ | 5-21-2003

[Stultis]

Should we then be surprised that other species stay unchanged for 100's of millions of years?

There are no known species that have remained unchanged for 100's, or even 10's, of millions of years. Crocodiles, coelacanths, horseshoe crabs, etc, are were very similar in the very ancient past to forms currently living (and I think in the later two cases -- somebody correct me -- may even belong to the same genera) but they are not the same species.

[Dataman]

Your nonsensical rants bore me.

[DManA]

The common scientific belief has been that army ants originated separately on several continents over millions of years. Now it is found there was one evolution. Using fossil data and the tools of a genetics detective, a Cornell University entomologist has discovered that these ants come from the same ancestor, because since the reign of the dinosaurs, about 100 million years ago, army ants in essence have not changed a bit.

http://www.news.cornell.edu/releases/May03/ArmyAntBrady.bpf.html

[Stultis]

But they still aren't the same species, not even living army ants.

[DManA]

The article says, in clear English, that today's army ants are exactly the same as their ancestors 100 million years ago.

[Stultis]

Say, ever going to present a stating of the theory of evolution that addresses life origins, or are you just going to claim that you did despite the fact that I exposed your "references" as anything but?

Arm-waving textbookese about ancient seas filling with water and organic chemicals is, clearly, all he ever had.

Ho-hum indeed.

[Stultis]

The article says, in clear English, that today's army ants are exactly the same as their ancestors 100 million years ago.

Which is clearly hyperbole, since it also says all living army ants are descended from these "exactly the same" ancestors, yet living army ants vary significantly in morphology and behavior, and comprise different species.

[DManA]

The title of his artical is:

"Evolution of army ant syndrome: the unique origin and long-term evolutionary stasis of a novel complex of behavioral and reproductive adaptation"

Will be published on the Web by the Proceedings of the National Academy of Science (PNAS) Online Early Edition between May 5 and May 9 before being printed in PNAS.

[DManA]

Is this hyperbole?

"Biologists have wondered why army ants, whose queens can't fly or get caught up by the wind, are yet so similar around the world. Army ants have evolved only once and that was in the mid-Cretaceous period," says Sean Brady, a Cornell postdoctoral researcher in entomology, whose study was conducted while he was doctoral candidate at the University of California-Davis.

[Stultis]

But there is variation within the "army ant syndrome" regarding morphology, behavior of soldiers versus workers, bivouac behavior, foraging patterns, and so on. Again, "exactly the same" is clearly hyperbole since even living army ants are not "exactly the same".

[Stultis]

Is this hyperbole?

The claim that the general army ant ecological strategy only evolved once is not necessarily hyperbole. (I don't have enough information or background knowledge to evaluate it.) But the "exactly the same" business... Yes, that is hyperbole, for the reasons I've stated.

[DManA]

Here's my problem. Somehow I got the crazy idea that stasis meant "a state of static balance or equilibrium". Clearly it is a synonym for dynamic.

[PatrickHenry]

I don't understand the hangup over "stasis." A creature either produces mutant offspring or it doesn't. Reproduction can carry on for innumerable generations with a good record of faithfully re-creating the genetic material with which it started. The DNA replication process is chemically stable, most of the time. So reproductive stasis isn't all that remarkable.

Mutations are the exception, and a favorable mutation would be even more of an exception. If a species is doing well in its environment, we would expect it to persevere, relatively unchanged. An *isolated* mutant variety could eventually develop into a new species, but the parent stock could continue to exist unless something comes along that wipes it out.

Over time, as a result of occasional isolated mutant populations, there can be a great variety of closely-related species. The mosquito, for example, is said to have 3,000 different species. Perhaps one of them is still the same as the original. This is not a problem for evolution.

[AndrewC]

Is this another worm conjecture?

[Aric2000]

Stasis placemarker for me.

[stanz]

another stasis placemarker

[<1/1,000,000th%]

While fast evolutionary change has been seen in fruit flies, such rapid evolution in a mammal has not been reported before.

Just shows what happens when you spend enough time in the city.

[Dimensio]

Ah, so you're not going to support your assertion with facts, because your assertion was wrong all along. I thought as much.

[Dimensio]

Textbookese? One of his "quotes" came from a pagan website. None of them, of course, were actually claiming to be statements of the theory of evolution despite his lies to the contrary.

[Dataman]

Ah, so you're not going to support your assertion with facts, because your assertion was wrong all along. I thought as much.

I gave you facts and you, as predicted, found excuses to ignore them. I can't make a blind man see.