But these supersized snoots are constantly serving up surprises—and a group of researchers has now discovered that they’re discerning enough to distinguish more from less. Their study, published today in the journal PNAS, suggests elephants can use scent alone to differentiate between quantities of sunflower seeds that might flummox even the most hawk-eyed of humans.

— Read more at Elephants Can Use Scent to Distinguish More From Less at NOVA.

Mosquitoes searching for a meal of blood use a variety of clues to track down humans, including our body heat and the carbon dioxide in our breath. Now, research shows that a certain olfactory receptor in their antennae also serves as a detector of humans, responding to smelly chemicals in our sweat.

— Read more at How Mosquitoes Sniff Out Human Sweat To Find Us at NPR.

Scientists have discovered that repellent odors suppress the perception of pleasant smells. This happens because certain brain structures that respond to attractive odors are inhibited by a repellent one.

— In vinegar flies, anyway. Read more at A repellent odor inhibits the perception of a pleasant odor in vinegar flies at Science Daily.