|MadSci Network: Medicine|
This is not in my field, but I'm going to take a crack at it anyway. Men may not brood like a woman does, but I believe that they do desire to father children. I believe that starting at puberty men strongly desire to father children. However, they do not have nearly as strong a desire to take care of and raise the children as women do. They are kept around by the desire to ensure that their genes are passed on by taking care of their children. Women also do not advertise when they are ovulating like in other species, so it is in the man's best interest to stick around so that no one else impregnates his partner. The pair bond formed with his mate is another reason he stays around. Women have high voices which help elicit the protective male response as if she were a child. Also men are able to father children all of their adult lives, but when have a limited number of fertile years. Perhaps brooding is your body's way of saying hurry up, you don't have much time.
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