Sunday, December 17, 2006

news @ nature.com - People track scents in same way as dogs - Human reputation for poor sense of smell is down to lack of practice.

news @ nature.com - People track scents in same way as dogs - Human reputation for poor sense of smell is down to lack of practice.: "If you think only hounds can track a scent trail, think again: people can follow their noses too, a new study says. And they do so in a way very similar to dogs, suggesting we're not so bad at detecting smells — we're just out of practice.

Scientists have found that humans have far fewer genes that encode smell receptors than do other animals such as rats and dogs. This seemed to suggest that we're not as talented at discerning scents as other beasts, perhaps because we lost our sense of smell when we began to walk upright, and lifted our noses far away from the aroma-rich earth."

1 comment:

chuck said...

"We have a much better sense of smell than rats and dogs because of our greater brainpower," says Shepherd. "This shows that in a few training sets, humans can achieve something that other animals spend their life being trained to do." --Shepherd

I call bullshit. I call bullshit on the whole article, which is frankly bizarre. I don't know if the fault lies with Shepherd or the reporter, although the latter is a good bet. Especially as the more controversial claims of Shepherd get more play than the remarks of Porter, who was actually involved in the experiment. The key point is delivered by Porter at the end of the article: "Our work certainly proves that if you can smell something, you can improve your ability to track it..." Well sure, practice makes perfect. But that is much less stunning than the claim that the "Human reputation for poor sense of smell is down to lack of practice."

Now, I have read of a servant in India sorting laundered clothes by smell, but such tales are rare and possibly not true. There are also folks with unusually sensitive noses who can get jobs sniffing subway tunnels for gas leaks and such. And some hunters can smell deer. But I think ordinary experience shows that the normal sensitivity of people to smells is less than, say, a hound. Otherwise, why employ dogs at all except that they are closer to the ground? The experiment itself is interesting but didn't address sensitivity as far as I can tell.

Arrggghhhh.