美国科学60秒 SSS 2012-11-14(在线收听

 Imagine if you could focus your nose the way you focus your eyes. Scientists now believe that animals with a highly developed sense of smell like rats and dogs, do just that. Similar to the way we taste sweet, salty sour and bitter on different parts of the tongue, animals detect various smells in different parts of the nose. Researchers at the University of Chicago hypothesized that rats by changing the way air flows across the insides of the nostrils could direct the scent that nasal region where could best be tested. Turns out they were right. When presented the different *ders , rats actually change the way they sniffed. For example, long slow sniffes. For hard to detect scents.Or short fast ones for easy ones.  Rats even sniff differently while learning a new scent than when the smell was familiar. The study is in the journal of NeuroScience. 

 
The researchers say the finding shows that there is more to a good sense of smell than originally thought. A sensitive nose is important, but so as how you use it. 
  原文地址:http://www.tingroom.com/lesson/sasss/2012/11/216411.html