Fathers as Biological Stimulus

One can only extrapolate so much from this news, but it's certainly interesting — especially given various discussions of family types:

Conventional wisdom holds that two parents are better than one. Scientists are now finding that growing up without a father actually changes the way your brain develops.

German biologist Anna Katharina Braun and others are conducting research on animals that are typically raised by two parents, in the hopes of better understanding the impact on humans of being raised by a single parent. Dr. Braun's work focuses on degus, small rodents related to guinea pigs and chinchillas, because mother and father degus naturally raise their babies together.

When deprived of their father, the degu pups exhibit both short- and long-term changes in nerve-cell growth in different regions of the brain. Dr. Braun, director of the Institute of Biology at Otto von Guericke University in Magdeburg, and her colleagues are also looking at how these physical changes affect offspring behavior.

Generally speaking, it has seemed to me that nature sets upper and lower boundaries as well as proclivities, while nurture directs the individual within that range. Ultimately, it makes no sense to draw a stark line between biology and psychology; they're more of a continuum.