Female moles evolved to have high testosterone levels, making them fiercer diggers and mothers. Female hyenas share this trait, but it means they must give birth through a male-like phallus.
Men and women who report a decrease in sexual activities are more likely to experience a deterioration in how they rate their overall level of health.
How do we get get aroused? And how can this happen without noticing it? Do the sounds we make during sex mean anything? Could rats help us figure these questions out?