美国科学60秒 SSS 2012-11-14

（单词翻译）

 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 nostrils¹ could direct the scent² that nasal region where could best be tested. Turns out they were right. When presented the different *ders , rats actually change the way they sniffed⁴. For example, long slow sniffes. For hard to detect scents⁵.Or short fast ones for easy ones.  Rats even sniff³ differently while learning a new scent than when the smell was familiar. The study is in the journal of NeuroScience.