Determining the animal with the most robust sense of smell is difficult since various olfactory receptors detect different odors. Olfactory receptors work to detect odorants resulting in the sense of smell. These receptors are in millions and mainly concentrated at the nasal cavity’s back area where they form an olfactory epithelium. Different species have varying numbers of scent-detecting genes. A study on different species concluded that elephants, bears, and sharks are some of the animals with a strong sense of smell.
Animals With the Strongest Sense of Smell
Bears are believed to have the most robust sense of smell of all animals on the planet. Although the brain of a bear is about one third that of a human, the area that controls the sense of smell is five times the size of humans. On this note, a bear’s sense of smell is 2,100 better than that of a human. Bears use this keen sense of smell to find food and mates, avoid danger, and also keep track of cubs in the wild. A bear can detect an animal’s carcass that is about 20 miles away, and polar bears can follow a sexually receptive sow’s scent over 100 miles.
Among sharks, a study shows that the great white shark has the most significant olfactory bulb. The sense of smell is controlled by about two-thirds of the shark’s brain. A shark can pick up the slightest drop of blood over a mile away, and its speed makes it a deadly predator. Sharks have their nostrils below the snout which water flows through continuously.
The African Elephant has the most significant amount of scent-detecting genes numbering 1,948. An elephant’s sense of smell is most reliable when dealing with water. Elephants can detect water 12 miles away. An elephant’s trunk has numerous receptors mainly for smelling and grasping among other uses.
Kiwis being flightless birds have to find their food while on the ground. Kiwis have external nostrils at their beaks’ tips, which ease food search beneath the soil and among the leaf litter. Kiwis have the second most significant olfactory bulb in all birds, giving the Kiwis a strong sense of smell.
Like bears, snakes have an organ in their mouth called Jacobson’s organ that identifies different scents. The sense of smell of a snake is highly developed and robust, and it uses its tongue to catch scent particles which in turn move to the Jacobson’s organ for identification.
The insect world has the male silkmoth as having the most definite sense of smell. The feathery antennae of moths contain scent receptors. Male silkmoths can spot a single pheromone scent particle from a female more than six miles away.
The Sense of Smell In Mammals
In mammals, about 20,000 genes are linked to the sense of smell, of which only close to half the number are used for practical purposes. The mammalian nose contains millions of olfactory receptors that work to detect distinctive smells. Research in Tokyo found out that olfactory receptors were the most significant multi-gene family in mammals. The study discovered over 10,000 unique genes with only three being common among mammals.