London: Scientists have revealed a previously undiscovered ability of bowhead whales' to smell the air - a finding that could change the understanding of how they locate prey.
The whales' sense of smell was revealed when scientists dissected their bodies and found olfactory hardware linking the brain and nose, and functional protein receptors required to smell.
Cetacean expert Hans Thewissen of the Northeastern Ohio Universities College of Medicine and colleagues based in Japan and Alaska made the discovery while calculating the brain size of bowhead whales.
The whales had been landed as part of the biannual Inupiat subsistence hunt along the north coast of Alaska, and Prof Thewissen's team was allowed to dissect the brain cavities, to evaluate how much of the brain casing a bowhead whale's brain actually fills.
"Upon taking a brain out, I noticed that there were olfactory tracts, which, in other mammals, connect the brain to the nose," the BBC quoted Thewissen as saying.
"I followed those to the nose, and noted that all the olfactory hardware is there.
"At first glance, it would appear that whales would not have much use for smell, since everything they are interested in is below the water. Olfaction is, by definition, the reception of airborne molecules," explained Thewissen.
The researchers also found that bowheads have mostly functional olfactory receptor proteins, which toothed whales do not. These provide the biochemical infrastructure for the marine mammal to sample odours.
"It is remarkable that this animal, which appears to have very little use for olfaction, retained that sense," Thewissen said.
"We speculate that they are actually able to smell krill and may use this to locate their prey. Krill smells like boiled cabbage," he added.
The details of the findings were published in the journal Marine Mammal Science.
First Published: Sunday, August 08, 2010, 11:49