"Still just a lizard" (evolution of novelty in 30 generations)

[phantom power]

Here's the story: in 1971, scientists started an experiment. They took 5 male lizards and 5 female lizards of the species Podarcis sicula from a tiny Adriatic island called Pod Kopiste, 0.09km2, and they placed them on an even tinier island, Pod Mrcaru, 0.03km2, which was also inhabited by another lizard species, Podarcis melisellensis. Then a war broke out, the Croatian War of Independence, which went on and on and meant the little islands were completely neglected for 36 years, and nature took its course. When scientists finally returned to the island and looked around, they discovered that something very interesting had happened.

(...)

The original P. sicula were insectivores who occasionally munched on a leaf; approximately 4-7% of their diet was vegetation. The P. sicula of Pod Mrcaru, though, had adopted a more vegetarian diet: examining their gut contents revealed that 34% of their diet was plants in the spring, climbing to 61% in the summer…and much of this diet was hard-to-digest stuff, high in cellulose. This is a fairly radical shift.

There were concomitant changes. The lizards' skulls were wider, deeper, and longer, and they had stronger bites — a necessity for chomping off bits of tough plants, instead of soft mosquitos. Instead of chasing bugs, they're browsing stationary plants, and their legs are shorter and they are slower. Population densities are higher. The Pod Mrcaru lizards no longer seem to defend territories, so there have been behavioral changes.

(...)

Now here's something really cool, though: these lizards have evolved cecal valves. What those are are muscular ridges in the gut that allow the animal to close off sections of the tube to slow the progress of food through them, and to act as fermentation chambers where plant material can be broken down by commensal organisms like bacteria and nematodes — and the guts of Pod Mrcaru P. sicula are swarming with nematodes not found in the guts of their Pod Kopiste cousins.

http://scienceblogs.com/pharyngula/2008/04/still_just_a_lizard.php#more

http://news.nationalgeographic.com/news/2008/04/080421-lizard-evolution.html

[pleah]

1. I like lizards. They eat

a ton of bugs out of my yard. I have gecko, anole(we call the chameleons) and two kinds of skinks.

[semillama]

2. That's great stuff!

Even better than the moth example of evolution in action.

[Nihil]

3. That's going to be an example for humans in the near future ...

Anything that can survive on whatever is around them will survive.
Those that can't, die.

Life's a bitch in the raw isn't it?

[On the Road]

4. That is Really Interesting

The evolution of cecal valves is astounding. Perhaps the gene set for those valves was already lying dormant in the lizards' DNA.

The one good argument that I beleive creationists have is that the original mechanisms for evolution do not produce change at a fast enough rate to account for the diversity of life on earth.

Now it seems evolution can happen fairly rapidly. Almost rapidly enough for experimentation.