I think perhaps the physical dimorphism is rather easily explained by the fact women have to carry children. Psychological dimorphism would be somewhat more su

I think perhaps the physical dimorphism is rather easily explained by the fact women have to carry children. Psychological dimorphism would be somewhat more surprising - after all, both mother and father gain from looking after the children. There's no specific biological machinery required to be a parent after the kid is born. That all said, I think this is over-individualizing the problem of passing on genes. If you take a dog, and a wolf, superficially they are similar. However, wolves are successful because of their complex social structure. So sexual dimorphism could be really misleading, because it's not the body of the wolf that matters, rather its social network. The sexual dimorphism could be an unimportant, anterior characteristic, a bit like the appendix, or the colour of the fur. When you take humans, who have an even more complex social structure, and more, one that has been extremely gender dimorphic, then consider the organ that's most obviously affected by social morphisms of all kinds... It sounds like a recipe for bad research. Especially when it's a topic people have an axe to grind about.