The bloodhound has the best sense of smell of any dog. Its nose has 40 times more scent receptors than a human nose – they have been referred to as ‘a nose with a dog attached’. Bears have noses that trump even that. A polar bear can smell a seal that is buried under a metre (3.2 feet) of snow from over a kilometre (0.6 miles) away! Mammals generally have the best noses. But the best smeller of all doesn’t have a nose at all. Male moths use their feathery antennae to comb scent molecules out of the air as they fly, rather than sucking it up through a nostril. Theirs is a highly specialised sense that has evolved to pick up just a single smell – the one emitted by female moths. The male Indian luna moth (pictured right) can detect a single molecule of sex pheromone from 11 kilometres (6.5 miles) away.
Answered by Luis Villazon
To learn more about all the incredible animals on our planet, why not visit our AnimalAnswers website – from the makers of How It Works.