http://www.medicalnewstoday.com/articles/121534.php
Our results show that diet and parental care have had an important influence on total brain size. Moreover, by analyzing males and females separately, we show that females caring for offspring alone have larger brains than females sharing care with their partner.
Can't read the whole article since you have to be a member, but maybe someone here is and can get us this article? It sounds interesting.

