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We Finally Have it! Indisputable Proof of Evolution!!

by RebelSnake | Published on April 28th, 2008, 12:14 pm | Science
http://scienceblogs.com/pharyngula/2008/04/still_just_a_lizard.php
Still just a lizard
Category: Evolution • Organisms • Science
Posted on: April 23, 2008 10:55 AM, by PZ Myers


The title gets the principal objection of any creationist out of the way: yes, this population of Podarcis sicula is still made up of lizards, but they're a different kind of lizard now. Evolution works.

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 population of P. sicula was still present on Pod Kopiste, so we have a nice control population. These lizards are small, fast, insect-eaters in which the males defend territories.

Sadly, P. melisellensis on Pod Mrcaru had been extirpated. So we had a few innocent casualties of the experiment.

The transplanted P. sicula thrived and swarmed over the island of Pod Mrcaru, but they were different, and they had evolved in multiple ways.

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.

Still just a lizard, I know.

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.

Here's a photo (how could I resist an opportunity to show some lizard guts?). The top ones may be a little difficult to interpret; what they've done is slit open the tube of the gut, and then use some pins to hold the tube open so you can see the little ridge or flap that rings the interior.


Photographs illustrating the cecal valves in a male (A), a female (B), and a hatchling (C) P. sicula from Pod Mrcaru. Note the thick cecal wall and pronounced ridges. The arrow in C indicates the position of the cecal valve in a hatchling as seen from the outside.
The cecal valves are an evolutionary novelty, a brand new feature not present in the ancestral population and newly evolved in these lizards. That's important. This is more than a simple quantitative change, but is actually an observed qualitative change in a population, the appearance of a new morphological structure.

Evolution created something new, and it did it quickly (about 30 generations), and the appearance was documented. It's still just a lizard, but we expected nothing else — and it's now a lizard with novel adaptations for herbivory.


--------------------------------------------------------------------------------

Herrel A, Huyghe K, Vanhooydonck B, Backeljau T, Breugelmans K, Grbac I, Van Damme R, Irschick DJ. (2008) Rapid large-scale evolutionary divergence in morphology and performance associated with exploitation of a different dietary resource. Proc Natl Acad Sci U S A. 105(12):4792-4795.


Well now, even the most hard core beLIEver is going to have a rough time attempting to explain this one away. Indisputable, undeniable proof of evolution in action. The appearance of a totally new structure that wasn't there before and it's been fully documented by the scientific community.
Attachments
cecalvalves.jpg
 
 
Let me put on my BHL face mask
"It's just micro-evolution, it's not a lizard-boy"

Now my Sterling mask
"Your very foundation for knowledge rests on the assumption of Jesus Christ to whom you will bow your bended knee. Repent."

<cut and paste lengthy and irrelevant bible passage>
1:3 But Jonah rose up to flee unto Tarshish from the presence of the LORD, and went down to Joppa; and he found a ship going to Tarshish: so he paid the fare thereof, and went down into it, to go with them unto Tarshish from the presence of the LORD. (1:3, 10)
Jonah fled "from the presence of the Lord." (There are some places where God can't find you.)
Does God know and see everything?
1:4 But the LORD sent out a great wind into the sea, and there was a mighty tempest in the sea, so that the ship was like to be broken. Jonah's ship in the storm
(Unknown, 1712)
1:5 Then the mariners were afraid, and cried every man unto his god, and cast forth the wares that were in the ship into the sea, to lighten it of them. But Jonah was gone down into the sides of the ship; and he lay, and was fast asleep.
1:6 So the shipmaster came to him, and said unto him, What meanest thou, O sleeper? arise, call upon thy God, if so be that God will think upon us, that we perish not.
1:7 And they said every one to his fellow, Come, and let us cast lots, that we may know for whose cause this evil is upon us. So they cast lots, and the lot fell upon Jonah. </cutandpaste>
All stupid ideas pass through three stages. First, it is ridiculed. Second, it is ridiculed. Third, it is ridiculed
April 28th, 2008, 12:26 pm
User avatar
A Person
 
Location: Slightly west of the Great White North
A Person wrote:Let me put on my BHL face mask
"It's just micro-evolution, it's not a lizard-boy"

Now my Sterling mask
"Your very foundation for knowledge rests on the assumption of Jesus Christ to whom you will bow your bended knee. Repent."

<cut and paste lengthy and irrelevant bible passage>
1:3 But Jonah rose up to flee unto Tarshish from the presence of the LORD, and went down to Joppa; and he found a ship going to Tarshish: so he paid the fare thereof, and went down into it, to go with them unto Tarshish from the presence of the LORD. (1:3, 10)
Jonah fled "from the presence of the Lord." (There are some places where God can't find you.)
Does God know and see everything?
1:4 But the LORD sent out a great wind into the sea, and there was a mighty tempest in the sea, so that the ship was like to be broken. Jonah's ship in the storm
(Unknown, 1712)
1:5 Then the mariners were afraid, and cried every man unto his god, and cast forth the wares that were in the ship into the sea, to lighten it of them. But Jonah was gone down into the sides of the ship; and he lay, and was fast asleep.
1:6 So the shipmaster came to him, and said unto him, What meanest thou, O sleeper? arise, call upon thy God, if so be that God will think upon us, that we perish not.
1:7 And they said every one to his fellow, Come, and let us cast lots, that we may know for whose cause this evil is upon us. So they cast lots, and the lot fell upon Jonah. </cutandpaste>



I'd give your effort a B+ or an A-. For a truly A grade fakery of RD, you really need to paw through a thesaurus, choose multisyllabic words at random, and puree them into religiousword-soup regardless of those words' meaning or context. Then top with a cherry macerated in Repentance-syrup.
The Rapture already happened. All the good Christians are gone. We're stuck with the rejects.

"Why would anyone pray in private where no one can see you?"- BHL
April 28th, 2008, 1:44 pm
User avatar
C. Alice
 
A Person wrote:"It's just micro-evolution, it's not a lizard-boy"

"Your very foundation for knowledge rests on the assumption of Jesus Christ to whom you will bow your bended knee. Repent."


thanks for saving me the typing.

:-)
May 1st, 2008, 9:41 am
royaldiadem
 
See Poe's Law in action.
May 1st, 2008, 10:46 am
User avatar
A Person
 
Location: Slightly west of the Great White North
A Person wrote:See Poe's Law in action.

Huh. I hadn't heard of this "Poe's Law" ... it was inevitable that it should be seen as universal.
May 1st, 2008, 11:23 am
User avatar
SouthernFriedInfidel
 
Location: 5th circle of hell -- actually not very crowded at the moment.
This is our chance to change things, this is our destiny.
August 3rd, 2009, 11:36 pm
User avatar
Liv
I show you something fantastic and you find fault.
 
Location: Greensboro, NC

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