PZ Myers Trochlea Challenge

[Jefferson]

PZ Myers Trochlea Challenge

This is the show from Tuesday June 22nd, 2010.

SUMMARY:

The PZ Myers Trochlea Challenge: Well-known evolutionist PZ Myers published a blog titled Bob Enyart wants me to respect his intelligence. So we posted to his blog - "PZ, since you won't debate him, Bob Enyart has now posted what he's calling his one and only question to you: The PZ Myers Trochlea Challenge. It's a sketch of the human eye with the question." -A Bob Enyart Live stafferTrochlea challenge to evolutionists

* Today's show is an honorary edition of KGOV's Real Science Friday! See also, the YouTube of Bob Enyart's Chat with Paleontologist Jack Horner. Bob offers $20,000 to the scientist of Jurassic Park fame to Carbon-14 date the soft-tissue T-rex that he excavated. Take a look at the video, the $23,000 grant letter that Bob then sent to Montana State University, and see also photos of the soft-tissue that is not 65 million years old!

* Today's Resource: Have you browsed through our Science Department in the KGOV Store? Check out especially Walt Brown'
In the Beginning and Bob's interviews with this great scientist in Walt Brown Week! You'll also love Dr. Guillermo Gonzalez' Privileged Planet (clip), and Illustra Media's Unlocking the Mystery of Life You can consider our BEL Science Pack; Bob Enyart's Age of the Earth Debate; Bob's debate about Junk DNA with famous evolutionist Dr. Eugenie Scott; And the superb kids' radio programming, Jonathan Park: The Adventure Begins! And Bob strongly recommends that you subscribe to CMI's tremendous Creation magazine!

 

[Stripe]

I like it. :thumb: The atheists don't. :chuckle:

 

[fleablood]

Okay, if no-one has addressed the trochlea directly, I got my information primarily from the Richard Dawkins forum where it was discussed last Dec. and I owe my response entirely to one Devlo whoever he are she is and then did some googling on my own to verify I thoroughly understood.

Nearly all vertibrates have the eye cofiguration of the supior oblique muscle passing from behind the eye, through a looped trochlea, and then connecting to the eye. The difference between different animals is the position of the trochlea relative to the eye and therefore the angle of the bend in the dorsal oblique muscle. As the challenge states in a human the trochlea is above and in front of the eye so the angle of the bend of the "sling" is quite acute.
In an opposum though the trochlea is behind and above the eyebal so the angle is pretty oblique (about 120 degrees). In this article (well, I can't post the url, sorry) you can view these structures for the rabbit, pig, monkey, and cat. The article's a little old but I'm not a biologist so I simply grabbed what I could google.

The thing to note is that the position of the trochlea corresponds very closely to the orientation of the frontal bone (forehead on humans) . This implies the trochlea position did not evolve from natural selection for efficient eyeball movement but instead efficient eyeball movement was and adative response to trochlea position which itself is a result of the evolution of the frontal bone.

(Adaptive response {is that the correct term; I'm not a biologist} is very common in evolution. Probably the best known example is the lungs which evolved as a bouyancy bladder in fish and only then adapted in function to process air. The wings of the bat are probably another adaptive response to what were probably webbing evolved toward catching bugs. In fact, I think adaptive response is the general rule of evolution but a real biologist can probably address that better than I can.)