Salamnder said: "I would guess that the women who accept the idea of personality being at least partly dependent on genes are women who have had more than one child. That is the "a-ha!" moment for many of us, when we notice that our children all have such dramatically different personalities despite all living in the same environment." 
 
Yes, and the maturing child's emerging personality can develop the tastes, habits and perspective of a living or departed aunt or grandfather made flesh again. The maturation process is like watching the day-to-day transformation of a tadpole to frog. The process appears a miracle to us, but to the child or tadpole, its the path of least resistance, and contributed substantially to Man's belief in reincarnation.

"Other children do not share their interests, their vocabulary, or their desire to organize activities. They try to reform their contemporaries but finally give up the struggle and play alone... forms of solitary play develop, and these, becoming fixed as habits, may explain the fact that many highly intellectual adults are shy, ungregarious, and unmindful of human relationships, or even misanthropic and uncomfortable in ordinary social intercourse". 
 
An excellent reason why the highly gifted should have as many children as they can support. Siblings share each others interests and activities more seamlessly than non-siblings and it is much easier to change one's contemporaries as a group, than as an individual.

I think the 'Nature' editorial will eventually be viewed as much more measured and balanced than what the more politically correct 'Science' will publish.

I've been toying with the simple idea that slovenliness may be an infection. 
 
Perhaps not slovenliness by itself since it is too generalized, however, a more specific behavior like picking one's nose could be compelled by endoparasites.

Dogs are used in aging research since studies indicate their nervous systems fall victim to many of the same symptoms people do as they age. In fact, a query of dogs + aging in pubmed.gov will return 2045 documents. The MAO-B inhibitor selegiline is used to treat canine cognitive dysfunction syndrome after being used for years to treat senile senior citizens.