It is common knowledge that mice normally cower at even the scent of cats. This concept might be changing soon since some scientists from the Tokyo University have discovered a way to genetically engineer mice which show no fear towards felines.

Research team leader Ko Kobayakawa explained what they did to the mice to induce this kind of behavior:

Mice are naturally terrified of cats, and usually panic or flee at the smell of one. But mice with certain nasal cells removed through genetic engineering didn't display any fear.

People have thought mice are fearful of cats because cats prey on them, but that's not the case. If we follow the pathway of related signals in the brain, I think we could discover what kind of networks in the brain are important for controlling fear.