Japanese scientists create mice with no fear of cats

[Al-khiyal]

Tokyo, December 12, 2007 -- Tom and Jerry just wouldn't have been the same if it had featured one of Ko Kobayakawa's mice.

The Tokyo University professor has just unveiled mutant mice that have lost their innate fear of cats.

Rather than flee or freeze when confronted with their feline enemy, the mice sniffed and even played with them, blissfully unaware of the potential dangers.

Kobayakawa developed the fearless mice by shutting down receptors in their olfactory bulb - the area of the brain that processes information about smells - which would normally induce panic as soon as they get so much as a whiff of a cat.

In experiments with cats belonging to students, the genetically engineered rodents simply carried on as usual, sniffing and playing with their nemesis as if nature had intended them to be best friends.

"Mice fear cats because they are innately conditioned to fear when sensing the odour of the predators. So by getting rid of the specific receptors for sensing the odour, mice never feel afraid of cats," Kobayakawa told Reuters.

His research confirms the long-held belief among scientists that fear in animals is connected to their keen sense of smell.

"Once removing innate elements by which mice fear cats from them, we are able to make mice who can get along with cats," he said.

"So by applying this theory to other mammals, we will probably be able to make other animals that are not afraid of their natural enemies."

Inducing fearlessness in mice does not mean that cats, too, are ready to form unlikely friendships with their prey. Mochikko-chan, a cat used in a recent demonstration, was chosen because of her particularly docile nature.

Also, according to the researchers, even the modified mice froze in fear whenever the cats miaowed.

Video: Japanese scientists create mice with no fear of cats

[Bent_Bladi]

um....

[amalgamate]

wow. this theory may be in opposition to the psychological methods of conditioning animals to behave one way or another via a 'teaching' system.

or wait- maybe that doesn't include teaching them to be fearless.

[Al-khiyal]

Samedi 15 Décembre 2007 -- Les chercheurs de l'université de Tokyo ont génétiquement neutralisé l'instinct de la souris de se cacher lorsqu'elle repère l'odeur ou la présence des chats, ce qui suggère que la peur est génétique et non le fruit de l'expérience. “Les souris sont naturellement terrifiées par les chats et, habituellement, elles paniquent ou s'enfuient quand elles en sentent un, mais les souris privées de certaines cellules nasales par des manipulations génétiques n'ont donné aucun signe de peur”, explique Ko Kobayakawa, qui a dirigé la recherche publiée dans Nature le mois dernier. Lors de l'expérience, les souris génétiquement modifiées se sont approchées des chats, allant jusqu'à se frotter contre eux et à se montrer joueuses. Évidemment, a souligné le chercheur, il a utilisé des chats domestiques, moins enclins à profiter de l'amabilité du rongeur pour n'en faire qu'une bouchée. Les souris mutantes ont présenté d'autres changements encore, comme de cesser d'éviter la nourriture avariée, autre signe de l'atténuation de leur réponse à la peur.

Des souris qui défient les chats !