Listen to part of a lecture in a biology class.

So in certain mammals, when a female becomes a mother, we sometimes see a change in her behavior. She becomes less prone to fear. She becomes braver. One animal you see this in is the rat mother. Rats, it appears, actually become more courageous, braver when they become mothers. This is thought to be an effect of becoming a mother and enables her to take the risks necessary to search for food in the wild for her young. Scientists did an experiment with mother and non-mother rats that demonstrated this. They built a maze, a network of paths. It was a special maze with two types of paths. Some of the paths were enclosed like tunnels, so the rat would feel safe when exploring them, while other paths didn't have tops. They were open, so the rats could look out. These open paths were meant to be similar to open areas that rats typically avoid in real life because they offer no hiding places. So the rat would feel exposed in these open paths. Scientists observed the behavior of mother and non-mother rats in the maze to see if they acted differently, particularly with the open paths. What scientists noticed is that the non-mother rats chose mostly to stay in the safe-feeling enclosed paths. They seemed fearful of the open paths and were very hesitant about exploring them, some only walking a little way down and then going back. But mother rats, on the other hand, were much more confident about exploring the whole maze, both the enclosed paths and, unlike the non-mother rats, they boldly walked down the open paths too. And so too in the wild, this increased fearlessness, or bravery, would make it easier for mother rats to leave the safety of their nests and take chances, risk exposure to danger, and explore in order to find food for their young.