Eyes Work Without Connection to Brain: Ectopic Eyes Function Without Natural Connection to Brain
For the first time, scientists have shown that transplanted eyes located far outside the head in a vertebrate animal model can confer vision without a direct neural connection to the brain. Biologists at Tufts University School of Arts and Sciences used a frog model to shed new light — literally — on one of the major questions in regenerative medicine, bioengineering, and sensory augmentation research.
“One of the big challenges is to understand how the brain and body adapt to large changes in organization,” says Douglas J. Blackiston, Ph.D., first author of the paper “Ectopic Eyes Outside the Head in Xenopus Tadpoles Provide Sensory Data For Light-Mediated Learning,” in the February 27 issue of the Journal of Experimental Biology. “Here, our research reveals the brain’s remarkable ability, or plasticity, to process visual data coming from misplaced eyes, even when they are located far from the head.”
Read the Full Article Here: http://www.sciencedaily.com/releases/2013/02/130227183311.htm
In a Tadpole’s Eye: Another Case of Darwinism’s Plasticity Problem
Once you get over the slightly disturbing aspects of some recent experiments at Tufts University, you realize it’s just another fine demonstration of Darwinism’s plasticity problem that James Barham has repeatedly emphasized. Plasticity refers to the ability of animal bodies to remarkably adapt themselves to challenges that otherwise you might expect to be catastrophic. Tufts biologists have now succeeded in granting something close to vision to tadpoles by planting an ectopic eye in their tail. The eye has no connection to the brain, only to the spinal cord, yet somehow visual data is being effectively gathered and analyzed.
Here and at his own blog, Barham has pointed out that such plasticity cannot be accounted for in Darwinian terms: no animal in the history of life was previously rewarded by natural selection for being able to survive with visual information being somehow assimilated via the spinal cord (a serious enigma in itself) after its were eyes extracted and a friend’s eye surgically emplaced in its tail.
This is one of many amazing instances of similar phenomena. Barham has written:
Organisms of all sorts are capable of intelligent, goal-directed, adaptive behavior that cannot possibly be accounted for on the basis of the theory of natural selection.
Never in the evolutionary history of human beings was there selection for “seeing” with the tongue.
Never in the evolutionary history of fruit flies was there selection for adaptation to an inverted visual field.
Never in the evolutionary history of ferrets was there selection for the brain reorganization necessary to see with the auditory cortex.
And never in the evolutionary history of the slime mold was there selection for solving mazes.
Of course, the Darwinist will say that there is no need to posit past selection for plasticity. Instead, we will be invited to view plasticity as a “spandrel” — an accidental side effect of other abilities that were selected for.
But that would be entirely ad hoc. There is absolutely no evidence to support such a claim.
Moreover, it would be absurd, in terms of the relative significance of cause and effect.
To say that the massive reorganization exhibited by the brain in the first three experiments is a side effect of selection for some specific neural trait like vision would be like saying that binocular vision in all its complexity is a side effect of selection for the retina or selection for the lens. It would be to confuse the tail with the dog.
Another strategy that the desperate Darwinist might adopt would be to posit selection for an entirely general capacity for intelligent, goal-directed plasticity.
That is certainly a more promising way to go. However, such a strategy would still be tantamount to admitting defeat.
Why? Because it would be to acknowledge the existence of a fundamental, inherent, and quite general biological principle of what we might call “adaptivity.”
Why would that matter? Because the main task of Darwinian theory is to “reduce” teleology and normativity to mechanism.
Therefore, as soon as the Darwinist admits the reality of a general capacity for adaptivity extending throughout all of the living world, he has already given away the whole ballgame.
Read the Full Article here: http://www.evolutionnews.org/2013/03/in_a_tadpoles_e069691.html