Original photo by © olaser/iStock
Ever noticed the little vertical groove running down the center of a dog’s nose, connecting the tip of the nose to the upper lip? This narrow groove has a name: the philtrum, which is also the word for the vertical groove that stretches from the base of the nose to the upper lip on human faces.
Human philtrums develop in the womb as the face forms, but they have no known function. For our furry friends, though, the philtrum serves an important and fascinating biological purpose. Every time a dog licks its lips or nose — which they tend to do quite a lot — a small amount of saliva collects in this narrow channel.
Oops, incorrect!
It's a fibNo dog has ever piloted a plane all the way from London to Paris, but a British rescue dog named Shadow did learn how to fly a light aircraft, successfully completing a (deliberate) figure-eight maneuver at 3,000 feet in 2016.
Through a process called capillarization or capillary action (the same process that allows water to climb up the roots and stalks of plants), the saliva is gently moved up toward the nose pad, aka the leathery skin at the very tip of a dog’s muzzle. This helps keep a pup’s nose nice and moist — because a wet snout is much better at capturing scent molecules from the air.
The moisture helps to trap, dissolve, and hold onto odor particles so a dog’s 300 million or so olfactory receptors can efficiently analyze all the wonderful smells that permeate its environment. So when your very good boy or girl gives you a big kiss and immediately licks their nose, they’re not just being adorable — they’re instinctively topping up the moisture in their philtrum so they can better understand the invisible world of smells around them.
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The animal believed to have the best sense of smell is the ______.
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The animal believed to have the best sense of smell is the African elephant.
Some ants smell like chocolate when they’re angry.
Ants outnumber humans by a huge margin, with an estimated 20 quadrillion scuttling around at our feet. But have you ever smelled one? If so, you may have been surprised by the aroma. When angered, threatened, or squashed, many species of ants release potent chemicals that have distinctive smells. The species Tapinoma sessile, for example, is said to smell like rotting coconut, blue cheese, or turpentine when crushed, accounting for its unflattering common name: the odorous house ant, or stink ant.
But not all ants release unpleasant odors. The appropriately named citronella ant, for example, gives off a lemony odor when threatened or crushed. And then there’s Odontomachus, commonly known as the trap-jaw ant. In those same perilous situations, trap-jaw ants release a pheromone that warns other ants of nearby threats — but to humans, it smells like chocolate.
Tony is an English writer of nonfiction and fiction living on the edge of the Amazon jungle.
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