BOB HIRSHON (host):
Big brain trade-offs. I’m Bob Hirshon and this is Science Update.
We humans are justly proud of our big brains and intelligence. But if big brains are so useful, why don’t lots of animals have them? Researchers report in the journal Current Biology that they tried to find out by breeding strains of guppies with increasingly large brains and comparing them to their small-brained cousins. The large-brained guppies were significantly better at intelligence challenges, but they also had substantially smaller digestive systems and they left fewer offspring. They conclude that there are costs to having a large brain, and the trade-offs may be worth it for only a small number of species.
In other news, scientists report in the journal Neuropsychopharmacology that antidepressent drugs may stimulate production of new brain cells, and slow the progression of neurodegenerative diseases. So in addition to helping patients cope with these illnesses, antidepressents may also help treat them. I’m Bob Hirshon, for AAAS, the science society.