Top 10 Most Powerful Sense of Smell Animals

Dogs, closely associated with human life, possess incredibly strong smelling abilities. Members of the Canidae family, including wolves, wild dogs, foxes, and domestic dogs, have between 149 million to 300 million olfactory receptors. Therefore, canines are much more sensitive to smells than humans, as they can detect scents that we cannot perceive.

During this 'sniffing' process, a dog's nose is lined with a large number of olfactory receptors located on the conical-shaped mucous membrane, which receive and transmit signals about different molecules in the air to the brain. Here, the brain analyzes these molecules (and accurately identifies their source, whether it's food, compatible mates, friends, foes, or anything else) - however, in dogs, the surface area of this conical-shaped mucous membrane can reach over 10 square meters, while in humans, the corresponding area does not exceed 5 square centimeters.

In fact, Canidae family members use half of their brain devoted solely to receiving and processing olfactory signals, while humans use only about one-tenth of their brain. In summary, when it comes to sniffing, all members of the Canidae family achieve absolute victory over humans, from trained police dogs using their senses to detect substances like explosives, drugs, and the like, to search and rescue dogs that can easily find missing persons.

It's no surprise that snakes and lizards are listed in this ranking. In the world of snakes and lizards, the sense of smell has been remarkably enhanced. Instead of sniffing through the nose, these reptiles gather scent through their long tongues.

The tongue of a snake (and lizard) collects particles and molecules in the air as well as underwater and provides crucial information to the brain through two pits on the roof of the mouth, scientifically known as the 'Jacobson's organ,' where the molecules are analyzed, and it's determined whether they originate from a potential threat, a potential prey, or anything else — they can even accurately determine the direction from which these molecules are coming.

Thus, with their keen sense of smell, a Komodo dragon (the largest lizard species in the world) can detect prey or a decaying carcass from over 9 km away.

The next name on the list is the bear species. The olfactory sense of bears is incredibly strong – so much so that it surpasses that of any dog – strong enough to detect animal carcasses from over 32 km away. The explanation behind this extraordinary ability lies in the structure of their olfactory epithelium – a separate part of the brain responsible for receiving olfactory signals – which is at least five times larger than that of humans.

Bears also possess a large, developed snout containing hundreds of tiny muscles with dexterity comparable to human fingers. The surface area inside their snout contains more receptors than those of the dog species, thus, the bear's sense of smell operates exceptionally well, compensating for their relatively poor eyesight.

Moreover, it has been observed that bears have a better chance of sniffing out scents when they stand on their hind legs, significantly enhancing their olfactory capabilities compared to when they move on all fours.

One of the most keenly olfactory animals today is the African elephant, boasting nearly 2,000 receptors to detect scents. The olfactory cells are located in the nasal cavity and the thick skin near the tip of the trunk. According to The Telegraph, in the animal kingdom, perhaps the elephant's nose is the most extraordinary in terms of length, size, wide nostrils, and flexible movement.

Moreover, their sense of smell is also among the 'superlative' in the animal world. In 2014, the University of Tokyo, Japan, conducted a study on 13 well-known mammalian species with the most sensitive sense of smell on the planet, including humans.
The results showed that African elephants have up to 2,000 olfactory genes, twice as many as domestic dogs and five times as many as humans, surpassing the previous record holder, the mouse, with 1,200 olfactory genes.

Among all the fish species living under the ocean, Sharks are the ones with the keenest sense of smell, and because of that precise olfactory ability, there was a time when people believed they could accurately detect the location of a single drop of blood in the vast ocean.

The nostrils of a shark are located on the underside of its upper jaw and are lined with specialized cells including olfactory epithelium - as they swim, water flows through two nostrils and chemical molecules dissolved in water come into direct contact with this epithelium, allowing the receptor cells within the epithelium to capture and transmit signals to the brain for analysis and processing.

As a result, their sensory system is extremely sensitive. Moreover, similar to the aforementioned animal species, the olfactory strip of sharks develops to a very large size. Consequently, they can detect some of the smallest chemical traces within billions of gallons of ocean water, whether originating from a fat prey, a potential hidden threat, or a potential mate.

Opossums are renowned for their scavenging abilities, with 1,188 sensory receptors. Additionally, they possess an incredibly robust immune system, allowing them to be immune to viruses and snake venom.

An Opossum is a marsupial belonging to the Didelphidae family in the Didelphimorphia order native to the Americas. It is the largest marsupial order in the Western Hemisphere, comprising over 103 species across 19 genera. Opossums originated in South America and migrated to North America during the 'Great American Interchange' following the connection of the two continents. Their generalist biology, flexible diet, and reproductive habits have made them among the most successful survivors in various locations and conditions.

Opossums are also known for their adept tree-climbing skills, facilitated by their specially structured prehensile tail that aids in carrying food or dry branches back to the den, making them comfortable climbers. Sometimes, young ones even hitch a ride on the back of the mother Opossum during foraging.

Mice are animals equipped with a whopping 1,207 sensory receptors, facilitating convenient prey detection. They are highly ranked in olfactory ability. In fact, Harvard research indicates that mice are highly sensitive to odors, with some species even trained to detect scents specific to landmines and tuberculosis. Mice often rely on scent to distinguish members within the colony, as well as to discern food sources, enemies, mates, and more.

The Muridae family is found nearly everywhere worldwide, though many subfamilies have narrower ranges. They are absent from Antarctica and the oceanic islands. While no species originated in the Americas, some species, like house mice and black rats, have been transported worldwide by humans. They occupy a range of ecosystems from tropical rainforests to grasslands. While there are species that are arboreal, aquatic, or semiaquatic, the majority are terrestrial animals.

Loài ngựa có 1.066 thụ quan, là động vật có khả năng ngửi mùi giỏi bậc nhất so với các động vật có xương sống khác. Ngựa có tới 2 cơ quan khứu giác, một ở mũi giúp phân loại mùi, cơ quan thứ hai cũng trong mũi tên Vomeronasal organs hay Jacobson’s organs. Hai hệ thống thần kinh nối tới óc, có nhiệm vụ phân tích các mùi hormones kích động, như mùi của thức ăn, mùi nguy hiểm, hay mùi tình dục của ngựa đối ngẫu. Khứu giác ngựa nhạy tốt hơn người, nhưng chỉ thua loài chó. Đặc biệt ngựa rất nhạy cảm với dầu thơm, không nên xức dầu thơm khi gần ngựa, vì làm chúng trở nên rượng đực hay cái. Động vật họ Ngựa cũng có giác quan thứ sáu, cho phép các con đực có thể sử dụng phản ứng uốn môi trên để đánh giá tình trạng kích dục của các bạn tình tiềm năng.

Chúng có thể phát hiện mùi lạ cách xa hàng trăm mét. Cảm giác về mùi này qua trung gian tế bào cảm giác, ngựa có cảm giác mùi tốt hơn người. Ngựa có hai trung tâm khứu giác. Hệ thống đầu tiên làtrong lỗ mũi và khoang mũi, trong đó phân tích một loạt các mùi. Thứ hai, nằm dưới khoang mũi, là cơ quan vomeronasal, còn được gọi là cơ quan Jacobson (là một phụ khứu giác, cảm giác nội tạng được tìm thấy ở nhiều loài động vật). Có một đường thần kinh riêng biệt để bộ não cảm nhận và phân tích mùi (pheromones). Mũi cũng thính, có thể tìm được mạch nước ngầm sâu dưới mặt đất, hay mùi cách xa cả km.

Cattle, with 1,186 senses, ranks among the most keenly smelling animals. The sharp nose of cattle is said to detect odor from distances of 5-6 miles. They can also hear both low and high-frequency sounds beyond human hearing ranges.

Cattle is a collective term referring to mammals in the Bos genus, including wild and domestic forms. The Bos genus can be divided into 4 subgenera: Bos, Bibos, Novibos, Poephagus, but the distinction between them remains contentious. This genus currently has 5 surviving species. However, some authors consider this genus to have up to 7 species due to domesticated breeds also being considered separate species.

Representing amphibians on the list is the frog, possessing 824 senses. According to Professor Peter Banks, the frog's highly sensitive skin has helped them convey information through smell. However, Australian biologists argue that evidence has been found that frogs can also convey information through smell.

The natural habitat of frogs includes freshwater swamps, intermittent freshwater swamps, agricultural land, grasslands, rural gardens, urban areas, ponds, aquaculture ponds, irrigation canals, flood-prone agricultural land, channels, and ditches. They breed from spring to early summer.

Frogs coexist in wet areas near water bodies (ponds, water bodies, etc.). They feed at night. Prey usually includes insects, crabs, fish fry, worms, snails, etc. Additionally, Australian biologists argue that evidence has been found that frogs can also convey information through smell.