The elephant’s trunk is far more than a long, flexible snout. It is a complex fusion of the nose and upper lip, packed with muscles, nerves, and sensory cells. Scientists have discovered that elephants have an astonishing number of olfactory receptor genes—around 2,000 types—making theirs the largest repertoire of any species studied so far. By comparison, dogs, which are considered masters of scent detection, have about 800 to 1,000 receptor types, and humans only around 400.

— Read more in Elephants’ Incredible Sense of Smell: How They Detect Water from Miles Away at Vocal.

A recent study published in Current Biology has found that animals living at elevations of 1,000 meters and higher have a reduction in genes related to smell and a smaller olfactory bulb than similar low-altitude species. [...] Scientists found a 23% reduction in genes related to smell and an average of an 18% size reduction of the olfactory bulb, a kind of smell processing center located in the brain.

— Read more in Animals living at higher elevations found to have decreased sense of smell at Phys.org.

But in a study published on Wednesday in the journal PLOS One, Dr. Uchiyama and his team managed to achieve some research findings in feline behavior, establishing that cats respond differently to the scents of their owners than to the odors of strangers. That suggests your feline friend knows what you smell like, in addition to what you look and sound like.

— Read more in Your Cat May or May Not Love You, but It Knows Your Scent at The New York Times, or see Cats distinguish owner's smell from stranger's, study finds at BBC.