Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

What Is the Jacobson’s Organ (Vomeronasal Organ) In Dogs? Anatomy and Uses

close up of white and tan dog's nose

Most people know that dogs have an incredible sense of smell and can smell things that people can’t. However, that ability extends far beyond what most people realize. Dogs not only can detect scents that people can’t, but they can also smell pheromones using a unique organ located on the roof of their mouth.

This organ is known as Jacobson’s Organ or the vomeronasal organ. Below, we’ll run through everything you need to know about the vomeronasal organ, including whether people have one of their own.

divider dog paws 3 oct 2024

What Is the Vomeronasal Organ?

The vomeronasal organ is an accessory olfactory organ connected directly to a dog’s brain. It gets its name from the nearby vomer bone in an animal’s skull. This organ is present in all snakes and lizards and is also found in mammals such as dogs, cats, and cows. It is used to detect and interpret pheromones given off by other animals.

The vomeronasal organ is officially known as the vomeronasal organ but is also called Jacobson’s organ, or VNO for short. It gets its name from Ludvig Levin Jacobson, who studied it in various species in 1811.

Jacobson's Organ in Dogs
You’re welcome to use our images, but we require you link directly to this site for credit (ex. Image from Dogster)

Where Is It Located?

In dogs, the vomeronasal organ is located on the roof of the mouth and attached to the hard palate. It is located just behind a dog’s canine incisors. If you look closely at a dog’s mouth, you can often see it. It appears like a small mass on the roof of the mouth behind the front teeth.

What Do Dogs Use the Vomeronasal Organ For?

Dogs use the vomeronasal organ to smell pheromones, which are chemical signals given off by other dogs. Dogs do not have extensive vocal language like people do to communicate, so they use scents to figure out what is going on. Dogs use this ability to smell whether nearby dogs are happy, in the mood for mating, or scared. They give off pheromones in various situations, and other dogs can smell them.

For example, if a dog runs by and gives off fear pheromones, other dogs can deduce that the dog is scared and running away from something. This can also present itself in places like the veterinarian’s office and the shelter. Dogs can smell an overwhelming amount of fear pheromones in specific spaces, which can make them nervous.

The Jacobson’s organ is also one of the reasons why dogs sometimes sniff each other’s rear ends. Getting up into a dog’s space can give them clear access to the areas where pheromones are the most common. This allows them to get a good whiff of how the other dog is feeling in addition to what they’ve been eating and whether they are healthy.

You can see a dog attempting to use the organ to its fullest extent when they curls their lips back and opens their mouth while sniffing. This allows the organ to be exposed to the air and has a better chance of picking up the pheromonal scents, and it’s called the flehmen response. Goats and felines display the same behavior.

border collie dog licking nose
Image By: malcolmthe, Shutterstock

Do Humans Have a Vomeronasal Organ?

Do humans have a vomeronasal organ that they can use to smell pheromones? Unfortunately, they do not have one. Some people have remnants of the organ from ages long past, but the organ is not considered functional in humans. It is what is known as a vestigial organ. Many primates do not have a vomeronasal organ, which eliminates their ability to smell pheromones like dogs can. That means that anything that advertises calming pheromones for people is likely ineffective.

divider dog paws 3 oct 2024

Summing Up

Dogs have a unique organ in their mouth that allows them to smell pheromones from other dogs. This allows them to get a picture of what is going on around them with other dogs without using language to communicate. The Jacobson organ lets dogs know when other dogs are happy or scared. It also contributes to the infamous butt-sniffing behavior that fascinates people.

See also:


Featured Image By: PICNIC-Foto-Soest, Pixabay

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

How to Clean Dog Vomit on Hardwood: 4 Effective Methods

As a dog parent, you will inevitably have to clean up dog vomit, and if you have hardwood floors, they can just as...

Bearded Collie Dog Breed: Info, Pictures, Facts & Traits

The lovable Bearded Collie is a medium-sized dog that is smart, independent, and sometimes stubborn. With an athletic build and a lively personality,...

Dog Brain vs. Human Brain: Differences & Similarities

Putting dogs and humans in an evolutionary context is vital to appreciating the differences and similarities between their brains. Both share a common...

6 Amazing Boston Terrier Colors (With Pictures)

The Boston Terrier is a popular dog that makes a great companion. They originated in Boston, Massachusetts, and have been given quite the...

More related

Australian Silky Terrier Dog Breed: Info, Pictures, Care, & Facts

The Australian Silky Terrier is a charming purebred dog. This compact dog has a big personality, and people love them for their bright...

Do Pomeranians Like Water? Swim & Water Safety Guide

When the weather grows hotter, looking for opportunities to hop in some cool water is natural. Whether you have a pool or an...

Is a Cocker Spaniel a Working Dog? Facts & FAQ

Today, we know Cocker Spaniels as cute pups with dreamy eyes, adorable ears, and lovely personalities. However, originally, they were brought up to...

Can Dogs Drink Alkaline Water? Benefits & Safety Advice (Vet Answer)

You might have read about the health benefits of drinking alkaline water for yourself, but is the same true for your dog? Water...

Keep reading

Can Dogs Eat Hibiscus? Vet Approved Facts & FAQ

When growing plants in our garden, many dog lovers aren’t aware of the possible toxicity our beautiful plants have which can harm our pets. Hibiscus is a type of perennial flowering plant that adds beauty to many gardens and is...

Can Dogs Eat Hibiscus

Mossy Oak Nature’s Menu Dog Food Review 2025: Recalls, Pros & Cons

Review Summary Made in the USA and sold at Dollar General, Mossy Oak Nature’s Menu features two premium dry food recipes and three wet food formulas. Their dry food recipes are above average quality for cheaper food, but they’re not...

Dogster_Mossy Oak Nature’s Menu Dog Food Review

10 Best Foods for Husky Puppies in 2025 – Reviews & Top Picks

Siberian Huskies are working dogs who were bred to pull sleds across the tundra, but they’re also affectionate companions that enjoy being around humans and other pets. To keep your Husky puppy healthy, you’ll need to serve a nutritious diet...

young siberian husky eating

We Feed Raw Dog Food Review 2025: Our Expert’s Opinion

Has your dog had digestive issues? Have you often wondered whether his or her kibble could be the culprit? If so, you are not alone. It is something all pet parents go through at some point in time. You may...

Dogster_We Feed Raw Dog Food Review

Merrick Dog Food Review 2025: Recalls, Pros & Cons

Review Summary Garth Merrick founded Merrick Pet Care in 1988 out of a desire to create homemade food for his dog, Gracie. He crafted his recipes in Hereford, Texas, where the company still has offices. Merrick prides itself on producing...

Dogster_Merrick Dog Food Review

10 Best Dry Dog Foods in 2025 – Reviews & Top Picks

Dry dog food is convenient, long-lasting, and easy to store. It’s also highly nutritious, making it the most popular option for many pet parents. Of course, with this popularity comes a myriad of different brands on the market, some of...

measures a portion of dry dog food using an electronic scale

Can Dogs Eat Ginger Snaps? Vet-Verified Facts & Explanation

Ginger snaps are a spiced cookie that’s synonymous with the holiday season. They’re slightly sweet without being too overpowering, and deliciously crunchy. While you may enjoy them, ginger snaps aren’t something we recommend offering your dog. Ginger snaps aren’t inherently...

Can Dogs Eat Ginger Snaps

Can Dogs Eat Elderberries? Vet-Verified Facts & FAQ

The use of elderberries in human remedies has been on the rise over the past few years. You’ll find elderberry cough syrup on drug store shelves and elderberry jams and jellies floating around the grocery aisles. Not to mention, elderberry...

Can Dogs Eat_elderberries