Hi,
Sorry you didn't get a response before your paper was due. This message board isn't the kind of place to get immediate answers to general questions. It may take a day or more to get a reply and, more often than not, experts will refer you to a search engine for generic scientific questions. If you can show that you have done some work to find an answer and still need help ("I did a search for ... and found .... but I don't understand ...), you're more likely to get a helpful response.
Thank you for responding!! My paper got an "A" however I would still like some extra information on the brains of boys and girls if you don't mind. Again thak you for replying and have a great day!!
There are some papers on some historical roles of our ansestors that may or may not have scientific merit. Some theories suggest that somebody who is dependent on gathering food learns and remembers detailed knowledge of what, where, when in order to survive. Somebody who is dependent on hunting animals for food must learn and master a different set of skills that is less dependent on specific details of what, where, and when because animals move around more and display a wider range of behaviors than plants do (at least when you just considering one species at a time).
My personal opinion (which counts for nothing scientifically) is most of us just tend to remember what we need to or want to or care to remember unless we learned it the hard way and it gets "burned" in and we end up with the scars to prove it.
Those are good places to start; you might also try putting things like 'brain imaging' and 'differences in the brains of men and women' into Google or Google Scholar or a similar search engine.