Fact is, guys can form deep bonds with their female friends, too deep, sometimes. The signs are subtle at first ... like commenting negatively on her other male friends. If this is happening ...

The defense secretary promised that the United States would soon have the highest combat standards for men and women in the military.

Look at one and then the other. Can you tell which brain is female and which is male? You can't. Humanity has been hunting for sex-based differences in the brain since at least the time of the ...