Forge said:
Hormones and neurotransmitters not only determine behaviour, but are also involved in the regulation of how an animal grows up it's ontogeny. Belyaev and his followers concluded that by selecting each generation for a certain behavioural and biochemical profile, they had affected the master genes that control development through to adulthood. They had changed the conductor of the orchestra. "
This has been theorized to be what also caused human diversity as well, as well as most other mammals. Of course, an experiment like this with humans would be much harder to implement.
Dude you are right in a way, but it is not proved by this as far as evolution is concerned- we are speaking in terms of two different contexts....
There are two key phrases
1-"by selecting each generation for a certain behavioural and biochemical profile"...
Basically they were selecting for specific genes/gene expression levels... This is what the environment does (it determines which gene combinations will be more successfull and thus be a bigger part of the successive generations)
2-"Hormones and neurotransmitters not only determine behaviour, but are also involved in the regulation of how an animal grows up it's ontogeny"...
By definition Ontogeny means "The developmental history of an organism." or " the processes of growth and development of the individual from conception to death." it does NOT mean anything about evolution (which is based on actual genes, and not their use/activity), but rather the EXPRESSIONS of genes and the growth and development of the organism... it is well know that high stress levels can affect a organisms developmental rate and overall development patterns (ie giving a kid steriods can stunt development in a number of ways) these guys were not doing experiments as to mechanisms of evolution
In work that I personally have done previously, various chemicals/manipulations, etc CAN result in gene mutations, gene translocations, etc, in a variety of cells and tissues..... but the chance of this happening in any kind of gamete or offspring producing cell (thus affecting future generations) and resulting in a viable gamete or offspring if such an event were to take place is very low... (I did work in gene mutation/translocation in grad school)
gene mutations are RANDOM occurances the accumulate over time and result in differences in observed traits.... environment and other outside selective pressures (which is what the scientists played the role of in your study) then determine (by influencing the organisms fitness and survival success rates) which gene combinations will be passed on to future generations.... this is evolution...
