By DAVIDPERCIVAL
Added: Sun, 07 Nov 2010 12:42:42 UTC

A paper by D.Natt and others (2009) published under this heading shows that chickens who had unpredictable light when young demonstrated a more conservative strategy for finding food. It also found this resulted in a varied expression of the genes within the brain compared with comparators on a 12 hour/12 hour light/dark regime. They also demonstrated a more assertive behaviour when food opportunities were limited. This was a very interesting observation but even more interesting is that the offspring of the 2 sets of birds acted as their parents had done. This would seem to indicate that changes in gene expression can lead to a change in behaviour in offspring so changes in behaviour by one generation can be inherited by the next without the genes themselves being changed.

My understanding of Richard Dawkins thoughts on animal behaviour is that the animal's behaviour tends to maximise the survival of the genes "for" that behaviour.

He said somewhere I have seen on the internet "The point is that some genetic changes are passed on (otherwise there could be no evolution) but no environmentally acquired changes are passed on (at least with not enough high fidelity to have a chance of surviving into the indefinite future)."

Now if the offspring of the chickens mentioned above were also to be kept in variable light conditions it is possible the differences with the other chicken's descendants would grow more marked and therefore continue into the indefinite future. If so, this would appear to contradict one of the pillars of the neo-Darwinian dogma. Or am I missing something?

TAGGED: BEHAVIOR