Evolving Wing Patterns
by MikeGeneFrom here:
This finding is informative because it shows that the wing pattern wasn't generated from scratch," said Carroll. "The fly didn't use naïve DNA that had no job and invent this pattern out of thin air. It used a gene that was already active in the wing, already drawing some kind of pattern in the wing, and modified that pattern. We think that is strong clue to how nature invents, which is by using material that is already available. This demonstrates how evolution is a tinkerer," he said.
Yes, yes, evolution tinkers with what it is given.
The findings also underscore an important role for pleiotropic genes in evolution. "For example, a fly's body has pigmented bristles, mouth parts, thorax and abdomen. These different features are controlled separately, so the same yellow gene can be used in different parts of the body. So this pleiotropy gives evolution an artistic freedom to play with the regulatory elements in specific regions without making mutations that would affect the gene throughout the body."
Very smart.
"And studies of phenomena such as fruitfly wing spots show how evolution is not some one-off process. It repeats itself over and over.
They show that there is more than one way to tinker with the same gene, and by extension, to independently evolve the same trait," Carroll said.
Very persistent. And resourceful.
April 20th, 2006 at 11:01 am
Ok, having read the post and the report linked in the post, I still have to ask, what was the point of all this? Perhaps I overlooked something, but I did not see, on my first reading, anything that was particularly new or overwhelming. Certainly the expansion of detail I gained on the workings of genetics in fruitfly wing spots is interesting. Overall though, what I have to say merely echoes the comments given after each section of the post, with one addition, uuuuum, duh! For the most part, the overall thrust of the report, as I percieved it, seems to be rather obvious, and somewhat elementary for this day and age…
Comment by carbon14atom — April 20, 2006 @ 11:01 am
April 20th, 2006 at 12:22 pm
Carbon14,
I think Mike is commenting on how evolution is often reported to be 'intelligent' - without actually being intelligent. It's smart, resourceful and has the ability to tinker until the output is 'just so'. At least that's what I make of it.
Comment by Lurker — April 20, 2006 @ 12:22 pm
April 20th, 2006 at 12:44 pm
He describes evolution as an intelligent process, how interesting. As if the fly decided what to do.
-evolution is a tinkerer
-the fly used a gene to draw and modify a pattern
artistic freedom to play with regulatory elements
Teleology at its worst. Although I agree with Carroll that evolution is an extension of existing functionality, it is not a good way to describe evolution.
Comment by AdR — April 20, 2006 @ 12:44 pm
April 20th, 2006 at 3:13 pm
Sorry for putting this here, Mike, but there is not a general section where one can post.
Where has Joy been? Also, why has Dave Heddle's link been removed?
Comment by Doug — April 20, 2006 @ 3:13 pm
April 20th, 2006 at 9:49 pm
Doug,
I saw Joy posting something a couple days ago, so she is around. As for Heddle's link, I don't know. Maybe it got misplaced when they added some others. We'll get it back up.
Comment by MikeGene — April 20, 2006 @ 9:49 pm
April 21st, 2006 at 4:20 pm
Mike,
If I understand your point, it's that pleiotropic genes look like they were designed to permit evolution to happen in some aspects of an organism, while maintaining stability in the rest of the organism. Am I close? And for us non-scientists (me, for example), I wonder if you could help us understand what pleiotropic genes are, and how they work.
Comment by Bilbo — April 21, 2006 @ 4:20 pm
April 22nd, 2006 at 3:38 pm
or not.
Comment by Bilbo — April 22, 2006 @ 3:38 pm