An Immense World: How Animal Senses Reveal the Hidden Realms Around Us

The common narrative that dogs have a strong sense of smell appears in the first chapter. While humans’ sensory perception of smell happens similarly to that of dogs, dogs have more of everything that enables smell. In addition, their noses have slits that send some air to the olfactory bulb, splitting it off from the main passage to the lungs, unlike human noses. The dog’s nose is designed so that sniffing does not scatter a scent trail but circulates it so that scent can be picked up better.

Yong makes the point that humans have recognized that dogs have a superior sense of smell to their own, but human recognition of this has generally resulted in exploiting that sense for people’s purposes, not in understanding what that sense of smell creates for the dog. As a result, people force dogs’ sense of smell to be of use within humans’ umwelt, rather than trying to understand how that sense of smell helps to create the dog’s umwelt.

Yong also challenges the myth that humans are not good smellers, tracing this false narrative back to the 1879 contention by Paul Broca that human olfactory bulbs are smaller than other animals’ and that smell is “animalistic” and not part of “higher” thinking.