Animals With an Amazing Sense of Smell: Unbelievable But True

Do you think the human nose can detect the slightest odor? You might be surprised, our sense of smell is actually very poor compared to most other animals.

Of all the animals, man has the poorest nose; he has virtually lost the sense of smell.

Humans are one of the smartest animals on the planet. But our noses? Not so impressive. Wine tasters and perfumers might disagree, but our sense of smell is quite weak. We rely on our brains to get out of tricky situations. Many animals, though, rely entirely on their noses to survive.

Some animals have an amazing sense of smell that makes the difference between life and death. Read on to meet the super-sniffers of the animal kingdom, the creatures that depend on their noses to win the race of survival.

Which Animal has the Best Sense of Smell

Some animals can sniff out prey from miles away. They can even smell danger coming and run to safety. Animals with a keen sense of smell are often those that can't see very well. Since their vision is weak, they make up for it by developing a powerful nose. A sharp sense of smell helps them find food and avoid becoming someone else's lunch. Let's look at some of the animals with the best olfactory (that's the science word for smell) ability on Earth.

Bear

At the top of the list is the bear. Bears have very big noses packed with thousands of smell receptors. They can detect a dead animal from 20 miles away. Bears can smell better than any other land animal on the planet. That's because the olfactory bulb (the part of the brain that processes smells) is 5 times larger in a bear's brain than in a human brain. What makes that even more impressive? A bear's brain is only one-third the size of a human brain!

The surface area of a bear's nose has 100 times more smell receptors than a human nose. Hundreds of tiny muscles inside their nose help them control and focus their sense of smell. So if you go camping in the woods, keeping food away from bears is very important. Leave your food supplies at least 100 yards away from where you sleep. Better yet, seal everything in a 100% odor-proof bag, bears can sniff out even tightly sealed containers.

Shark

In the ocean, the champion sniffer is the shark. Sharks can detect prey from a mile away. About 2/3 of a shark's brain is dedicated to the olfactory bulb, that's how important smell is to them. Any injured animal in the water, even a human, is not safe from a shark's sense of smell.

A shark's nostrils sit on the underside of its snout. In some sharks, like the nurse shark, there are also fleshy projections near the nostrils and mouth called nasal barbels. These help the shark taste and feel. Water flows through the nostrils constantly. This means a shark is always getting a fresh chemical picture of everything around it, 24 hours a day, 7 days a week. Not much escapes its notice!

Take the Animal Super-Sniffers Quiz!

5 questions. How well do you know the world's greatest noses?

Start Quiz

Bloodhound

Most dogs have a sense of smell 100 times better than ours. But the bloodhound goes even further. Studies show that a bloodhound's nose has about 230 million olfactory cells. That's about 40 times more smell receptors than a human nose.

The olfactory bulb in a bloodhound's brain is larger than in most other dogs, and far larger than in humans. When a bloodhound sniffs a piece of clothing, the smell reaches its receptors and is sent to the olfactory bulb. There, the smell is analyzed and an "odor image" forms in the dog's brain. The bloodhound can then pick out that one specific scent from hundreds of other smells and follow the trail to its source, even if the source is over 130 miles away.

Snake

Snakes smell their world with the flick of a tongue. They use their forked tongues to collect tiny airborne particles. A snake does have nostrils and nasal cavities, but those aren't used for smelling. Instead, snakes have a special organ called the Jacobson's organ (also known as the vomeronasal organ) in the roof of their mouth. When the tongue flicks out, it picks up particles and carries them back to the Jacobson's organ. The snake then builds a chemical picture of everything nearby using both taste and smell.

Snakes flick their tongues constantly. Each flick takes tiny samples from the air, soil, and water. The chemicals in those samples tell the snake whether a meal or a predator is nearby.

Even aquatic snakes, like the anaconda, can use their tongues to smell underwater just as well as land snakes can on dry ground!

Rat

When a rat breathes in, air flows through its nose and across a patch of skin packed with smell receptors. Odor particles latch onto tiny hair-like structures called cilia on those receptors. That triggers a signal in the rat's brain. Rats also have a vomeronasal organ (just like snakes) located in the lower part of the nasal passage near the septum.

The vomeronasal organ is especially good at detecting pheromones, the chemical signals that animals use to communicate with each other. This helps rats tell one another apart. Remarkably, there are about 500 to 1,000 genes in a rat that each code for a different type of smell receptor. That means 1% of the rat's entire DNA is dedicated to detecting odors and smells!

Rats have such a sensitive nose that they can be trained to sniff out land mines buried deep in the ground!

Frequently Asked Questions

Which animal has the best sense of smell?

Bears have the most powerful sense of smell of any land animal, 2,100 times better than a human's.

How does a snake smell?

Snakes flick their forked tongues to collect airborne particles, which are sent to the Jacobson's organ in the roof of their mouth.

How sensitive is a shark's nose?

A shark can detect a single drop of blood in about 25 gallons (100 liters) of water.

How many olfactory cells does a bloodhound have?

About 230 million (roughly 40 times more than a human nose) making a bloodhound's sense of smell 300 times better than ours.

More Super-Sniffers in the Animal Kingdom

These five animals are just a sample of the amazing sniffers in the animal kingdom. Many others are in the same league, moths, butterflies, bees, white-tailed deer, old world fruit bats, and polar bears all have an extraordinarily strong sense of smell. Even birds can surprise you. Birds like shearwaters, albatrosses, and the odd-looking kiwi all have an acute sense of smell.

As humans, we rely on our brains to get out of tough spots. Animals don't have that luxury. For many of them, it is smell (along with hearing and sight) that makes the difference between living and dying. Our noses simply can't detect the hundreds of odors our four-legged friends pick up every second. In a way, that might be a blessing. Imagine being able to smell every single scent around you all at once, that would be overwhelming! Animals have super abilities far beyond what humans can imagine. Each one is special and unique in its own way. Respect animals. They too deserve a chance to live with dignity.

Explore More Animals

Animals With an Amazing Sense of TasteWe think that, as humans, we have a highly developed gustatory modality that helps us enjoy and relish a number of dishes. Think again, as some animals have an 14 Animals With Really Strange Noses You Won't Believe are RealWe always wonder what was Mother Nature thinking when she decided to make certain animals look weird, and sometimes even creepy, especially their noses. In this Random Facts About Animals That Will Surprise YouSome really interesting facts about animals that you will enjoy reading. From elephants with 40,000 trunk muscles to hummingbirds that fly backwards, discover Mind-blowing Facts About Snakes That Will Leave You DumbfoundedThere's a lot more to snakes than most of us know. They are as intriguing as they are scary. An insight into the world of these fascinating reptiles proves why.

Smell Superpower: How Do They Compare?

Different animals achieve their extraordinary sense of smell in very different ways. Here's a side-by-side look at what makes each super-sniffer special: