Speciation in the lab?

[arcticpenguin]

http://www.sciencedaily.com/releases/2003/12/031208141435.htm

In what has been described as the "perfect experiment," evolutionary biologists at the University of Chicago replaced a single gene in fruit flies and discovered a mechanism by which two different "races" begin to become different species, with one group adapted to life in the tropics and the other suited to cooler climates. The tropical group was more tolerant of starvation but less tolerant of cold. The temperate group was less able to resist starvation but better adapted to cool weather.

The altered gene also changed the flies' pheromones, chemical signals that influence mating behavior. As a result, the researchers show in the Dec. 5 issue of Science, the two groups of flies are not only fit for different environments but may also be on their way to sexual isolation, a crucial divide in the emergence of a new species.

Let the quibbling over definitions begin.

 

[sorgoth]

Hmm....very interesting.

Although nowhere near the fly with the freakish amount of legs(Does anyone have a picture or link to that?)

 

[mummymonkey]

If there is no flow of genes between the two populations then they can be considered seperate species. So even though they may not be able to mate directly with each other, as long as there is a connection via intermediates, they are the same species. (As in domestic dogs & horses).
If these flies can't mate with any other intermediate type of flies, then I suppose they would be seperate species.
That's my understanding anyway.

 

[bug_girl]

funny thing, this just happens to be near my research field.
part of the species definition hinges on gene transfer--but few definitions actually specify HOW the genes get transfered. Rather like the discussion of whether "viruses are alive" going on elsewhere today, the answer depends on which biologist you ask.

There are quite a few bugs that can be induced to mate in the lab, but don't ever mate in nature. (one of my more memorable profs as an undergrad spent his time performing genetalia transplants on beetles, to see if given the proper "equipment" they could mate with different species.)

The one gene/pheromone shift has been seen in other insects, and usually pretty much shuts off any gene flow between populations. It usually doesn't take long for the populations to diverge. i work with two insect species that occasionally interbreed, but a) it's rare and b)the offspring don't do well.

If you define species as 100% always non interbreeding, then you are going to have issues. Nature is about blurry lines.

 

[Paul C. Anagnostopoulos]

The Creationists won't care because it was done in a lab.

~~ Paul

 

[Yahweh]

Speciation? Well that is just about the interestingest thing I've read all day...

 

[American]

Every day in the lab I go from jerk to nice guy, and back to jerk again. Does that count?

 

[pupdog]

More "lab" speciation...

In an earlier issue of Science (in October, I think), there was a description of speciation that appeared to develop from hybridization of sunflowers in the wild. The interesting part was that the investigators then duplicated the process, finding the hybrids would adapt to conditions that excluded the prior generation species, preventing backcrossing with the parents.

(Did Noah take 2 or 7 of each species of sunflower into the Ark?)

 

[pupdog]

Bug_girl said

If you define species as 100% always non interbreeding, then you are going to have issues. Nature is about blurry lines.

That really drives the Creationists nuts--they so like simple answers!

 

[zakur]

Although nowhere near the fly with the freakish amount of legs(Does anyone have a picture or link to that?)

Hmmm...I'll look. In the meantime, here's one with a leg in place of its antennae:

 

[zakur]

The Creationists won't care because it was done in a lab.

~~ Paul

Creationists won't care because the mutants are still fruit flies. From this page: "Fruit flies, subjected to laboratory induced mutations, may add or subtract wings and legs but continue producing fruit flies, ad infinitum---never butterflies nor dragonflies!"