Comments on: Blind cave fish see the light

By: My op-ed piece in The Calgary Herald - Albertans right to reject Darwinian evolution | Uncommon Descent

Sun, 17 Aug 2008 20:10:34 +0000

[...] bacteria evolve antibiotic resistance by junking intricate machinery, not by creating it. Cave fish lose their eyes. But we don’t need a theory for how intricate machinery gets wrecked. We need a theory [...]

By: Jonathan Sarfati

Jonathan Sarfati — Fri, 08 Feb 2008 17:25:52 +0000

Mutations can break things easily; it's much harder to make things. There are many possible ways a mutation could break eyesight (think of all the causes of human blindness for comparison). So ‘when you cross them, the genetic deficiencies in one lineage are compensated for by strengths in the other, and vice-versa.’ The evos would be onto something if they could find a mutation that could generate sight de novo, instead of merely allowing already-existing sight information to be expressed. See CMI's article Let the blind see … Breeding blind fish with blind fish restores sight.

By: ari-freedom

ari-freedom — Tue, 15 Jan 2008 10:55:06 +0000

this should be useful
http://bric.postech.ac.kr/biot.....nNum=91917

By: Clarence

Clarence — Mon, 14 Jan 2008 10:58:17 +0000

I would also want to see PaV’s evidnece relating to a mechanism whereby disuse of eyes is the trigger for eye-development repressing RNA to bee transmitted to its offspring.

By: Bob O'H

Bob O'H — Mon, 14 Jan 2008 06:58:35 +0000

Well, PaV – show us your evidence. And also how it would explain the data in the paper (e.g. how you get 12 estimated QTLs if the inheritance isn’t genetic, and also the pattern of complementation).

Bob

By: PaV

PaV — Mon, 14 Jan 2008 01:09:10 +0000

Bob #25:

Here’s a “just-so” story: through disuse of the eye, some type of RNA is transmitted to the progeny that is capable of repressing eye-development during embryonic growth. In the two populations, the RNA and its method of repression is slightly different. Since the genes needed for eye development are at no time absent, when these different populations are crossed, the differing RNAs don’t interact in the same way as in each native population, and eyes develop.

I like my “just-so” story better.

By: magnan

magnan — Sun, 13 Jan 2008 02:01:51 +0000

Vision is supposed to be very energy intensive, so another reason NS would tend to favor fish without the visual apparatus is that they would tend to have more metabolic energy to devote to food gathering, reproduction, etc.

By: DaveScot

DaveScot — Sat, 12 Jan 2008 09:47:41 +0000

I wish to concede a point about natural selection in this situation. I read an article that mentioned that fish eyes are subject to injury and infection, and that injury especially in total darkness would be greater as the fish can’t avoid running into cave walls and the like. Injury of course leads to infection and infection to death. So natural selection very likely is favoring fish with no eyes over those with eyes. That said, whether the visual system is functional or not is still irrelevant. Loss of the whole eye and replaced by a tougher covering would be the thing that was favored. It seems reasonable to presume that eyesight was lost much more quickly than the whole eye as the visual system could be damaged in many ways that don’t completely remove the eyeball.

By: Q

Sat, 12 Jan 2008 07:29:56 +0000

Bob O’H asks “What about three blind mice?”

If one of those three get their vision, the other two will disappear, because the first will “See how they’re one.”

By: Bob O'H

Bob O'H — Sat, 12 Jan 2008 07:02:40 +0000

Oh, but I should mention the real question that lies unanswered from the story:

Two blind fish can make sighted offspring.

What about three blind mice?

Bob