Technology Review describes some recent research suggesting female mice pass on environmentally acquired traits:
In Feig’s study, mice genetically engineered to have memory problems were raised in an enriched environment–given toys, exercise, and social interaction–for two weeks during adolescence. The animals’ memory improved–an unsurprising finding, given that enrichment has been previously shown to boost brain function. The mice were then returned to normal conditions, where they grew up and had offspring. This next generation of mice also had better memory, despite having the genetic defect and never having been exposed to the enriched environment.
Of course, deep in the trenches of the article, everyone hedges:
Feig, on the other hand, argues that while the findings are “a Lamarckian kind of phenomenon it’s still Darwinian, because the changes don’t last forever.” In Feig’s study, the offspring of enriched mice lost their memory benefits after a few months.
I’m just a layman here, but how are there not twin studies? Take two mice who are identical twins. Expose one to the enriched environment, the other to the less stimulating doldrums. Let them have offspring. How do the offspring of these two twins compare on a memory test? What would Judith Rich Harris say?