[Taxacom] larger brained taxa correlated more to diet (than to sociality or habitat)?
kinman at hotmail.com
Wed Nov 14 20:56:14 CST 2018
I watching a PBS program tonight on squirrels, and one researcher suggested tree squirrels have larger brains than ground squirrels since they have to navigate a more complex arboreal habitat. And there are also some squirrels that have brains that are larger in the autumn when they are trying to remember where they hid their caches of nuts and their brains then shrink to normal the rest of the year. Very interesting.
HOWEVER, some research seems to suggest that diet is a more important factor, at least in primates. If so, since rodents and primates are in the same clade (Glires), perhaps the rich diet of nuts in autumn accounts for larger squirrel brains that time of year, which also just happens to correlate with the need to remember the location of those hidden nuts? Anyway, here is a link to a paper on the subject in primates, suggesting frugivores have bigger brains than folivores. Folivores would not have a diet rich in fats (as in nuts) or sugars (as in fruits) that seem necessary for higher brain activity. Of course, sociality and arboreality could be secondary factors in some taxa, but folivores seem to be the least likely to develop larger or more complex brains that require more nutrients and energy.
More information about the Taxacom