Genetic and foster-parents’ exploratory type was measured in a novel environment pre-breeding and offspring exploratory type was assessed at adulthood. Offspring exploratory type was predicted by the exploratory behaviour of the foster but not the genetic parents, whereas offspring size was predicted by genetic but not foster-parents’ size.


They looked at one aspect of the adult behavior - "exploratory type". I don't think it's surprising that if a bird is raised by parents that explore a lot, then they'll more likely explore a lot.

How much of this transfers to humans is anyone's guess. But nurture makes more gut-level sense to me than a possible "gregarious" gene (for example) that dominates our personality. It makes more sense to me when it comes to dog behavior, too. The neurotic dogs I've come across have had obviously traumatic puppy-hoods.

One has to start somewhere in trying to figure out the nature/nurture relative importance, though. This seems like good incremental step.

As for why your kids are different - good question. I'm very different from my brother as well; but J and her twin sister have pretty big personality differences too (at least in some areas). It's a very large space of potential variables.

My $0.02.

Cheers,
Scott.