TOKYO, Japan (AP) -- The age-long animosity between cat and mouse could be a thing of the past with genetically modified "fearless" mice that Japanese scientists say shed light on mammal behavior.
Using genetic engineering, scientists at Tokyo University say they have successfully switched off the rodents' instinct to cower at the smell or presence of cats -- showing that fear is genetically hardwired and not learned through experience, as commonly believed.
"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," said research team leader Ko Kobayakawa.
"The mice approached the cat, even snuggled up to it and played with it," Kobayakawa said. "The discovery that fear is genetically determined and not learned after birth is very interesting, and goes against what was previously thought."
cute picture of a mouse and cat about to get into some major cross-species romance at:
http://www.cnn.com/2007/WORLD/asiapcf/12/13/japan.mouse.ap/index.html
