Why Do Dogs Sniff Each Other's Butts?

yanjf/iStock via Getty Images
yanjf/iStock via Getty Images

When dogs sniff each other's butts, they aren’t just huffing stale fart fumes, but “speaking with chemicals,” as the American Chemical Society puts it. A dog’s sense of smell is 10,000 to 100,000 times better than ours thanks to its large olfactory membrane, a lump of tissue tucked up in its snout that can be as large as a handkerchief and hold more than 225 million olfactory receptors. (Your olfactory membrane is puny by comparison—just the size of a postage stamp and home to only 5 million olfactory receptors.) Much dog-to-dog communication is done through smell.

When one dog greets another with a nose in the derrière, it’s basically getting a brief biography of its new friend, written in scent molecules and pheromones. To the sides of a dog’s butt are pouches called anal sacs; these contain glands which secrete chemicals that can tell a sniffer a lot of information about their owner, like gender, reproductive status, and clues about its health, diet, and even emotional state. It may seem like a strange way to go about it, but butt sniffing is just the canine version of shaking hands and introducing yourself.

The video below, from the American Chemical Society’s Reactions series, explains just what chemicals pooches use to make small talk and how that information doesn’t get overwhelmed by the less savory odors emanating from Fido’s backdoor.

15 Convenient Products That Are Perfect for Summer

First Colonial/Lunatec/Safe Touch
First Colonial/Lunatec/Safe Touch

The Fourth of July is the epitome of summer—and after several months spent indoors, you need some outdoor fun more than anything. Check out these 15 summer must-haves while they’re on sale and save an extra 15 percent when you spend $50 or more with the code JULYFOURTH15.

1. CARSULE Pop-Up Cabin for Your Car; $300 (20 percent off)

Carsule tent from Mogics.
Mogics

This tent connects to your hatchback car like a tailgate mobile living room. The installation takes just a few minutes and the entire thing stands 6.5 feet tall so you can enjoy the outdoors from the comfort of your car.

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2. Mosquito Killer Lamp; $30 (25 percent off)

Mosquito-killing lamp.
Kinkoo

If you just so happen to be one of those unlucky souls who attracts a suspicious amount of mosquitos the second you step outside, you need this repellent lamp to help keep your arms and legs bite-free. It uses a non-toxic combination of LED lights, air turbulence, and other methods to keep the pests at bay.

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3. Super Shield Mosquito Repellent Electronic Watch Band; $17 (57 percent off)

Mosquito repeller watch.
Safe Touch

While a lamp is a great non-toxic solution for keeping bugs at bay, active individuals need a bug repellent that can keep up with their lifestyle. This wrist wearable keeps you safe from mosquitoes anywhere by using ultrasonic sounds to drive them away.

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4. ZeroDark 3-Piece Tactical Set: Flashlight, Lantern, and Headlamp; $20 (66 percent off)

Aduro flashlight set.
Audro

If you want your summer to be lit, this set will do the trick. All puns aside, this trio of LED brightness is perfect for camping fun and backyard parties, or it can be stored in the car for emergencies.

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5. Outdoor Collapsible Cooler and Camp Table Set; $64 (27 percent off)

First Colonial cooler.
First Colonial

Cookouts are easy with this cooler and table set that chills your drink until you're ready to pop it into one of the four convenient cupholders. Bring this set camping or out by the pool for convenience anywhere.

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6. Trident: Underwater Scooter; $550 (21 percent off)

Trident underwater scooter.
Geneinno

If you’ve ever dreamed of better mobility while exploring the water, you’re not alone. The Trident underwater scooter, which raised over $82,000 on Indiegogo, can propel you through the water at up to nearly 6 feet per second, which isn't that far off from how fast Michael Phelps swam in his prime. The battery on it will last 45 minutes, allowing you to traverse with ease.

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7. Go Portable Solar Oven; $119 (14 percent off)

GoSun solar grill.
GoSun

Bake, roast, steam, or broil anywhere you bring this portable oven. Measuring in at just over a foot long and weighing only two pounds, the oven will work in most daytime weather conditions and can hold around 13 ounces of food.

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8. 3-in-1 Waterproof Bug Zapper Lantern; $25 (50 percent off)

3P Experts bug zapper.
3P Experts

Mosquitoes tend to be a big problem at night, partly because it's hard to swat in the dark. This lantern will light the area and zap mosquitos from nipping at you in the process.

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9. Urban E-Skateboard: Basic Version (Orange); $120 (73 percent off)

Urban Rover E-Skateboard
Urban Rover

This e-skateboard is perfect for getting around during the summer. You'll catch a breeze while you’re cruising on the battery-powered platform and won’t break a sweat when you pop the compact board in your bag.

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10. H2 Headlamp: Waterproof, Rechargeable LED Wide 180° Angle Headlight; $37 (26 percent off)

Headlamp from One80Light
One80Light

Camping, car troubles, and sports all pose a problem at night. This LED headlight will light up your surroundings across a 180-degree radius for prime visibility, meaning your outdoor activities won't have to stop when the sun sets.

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11. Whirlwind Cool Bladeless Mini Fan; $22 (63 percent off)

Bladeless fan
Whirlwind

This portable fan comes in a powerful handheld size so you can keep cool while on the move. Unlike other portable fans, this one has a sleek, bladeless design and features three different speeds.

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12. Bladeless Personal Fan; $22 (63 percent off)

Bladeless fan
3P Tech

This bladeless fan won't just keep you cool while you work on your laptop—it also has a built-in rechargable battery that you can use to charge your phone.

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13. MOGICS Coconut: Portable Waterproof Light; $37 (24 percent off)

Mogics portable lamp.
Mogics

This portable light is designed to adapt to your lighting preference. It self-inflates in a few seconds and can bounce, get wet, and set the mood.

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14. Lunatec 1L Hydration Spray Water Bottle; $25 (21 percent off)

Lunatec spray water bottle.
Lunatec

A water bottle can do more than hydrate you. This one has a spray nozzle that can create shower, stream, and mist patterns for doing dishes while camping, sharing a sip without sharing germs, and washing off those muddy shoes after a long hike.

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15. Sport Force Hydration Backpack; $25 (68 percent off)

Hydration backpack.
It's All Goods

Hiking enthusiasts know how important it is to stay hydrated, but carrying around awkward jugs of water is a hassle. This unique hydration backpack can be filled with two liters of water and features a convenient drinking nozzle that extends to the user's mouth. Now, you can replenish those fluids without breaking stride.

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The Reason Your Dog Follows You Everywhere

Crew, Unsplash
Crew, Unsplash

Depending on your mood, a dog that follows you everywhere can be annoying or adorable. The behavior is also confusing if you're not an expert on pet behavior. So what is it about the canine companions in our lives that makes them stick by our sides at all times?

Most experts agree on a few different reasons why some dogs are clingy around their owners. One is their pack mentality. Dogs may have been domesticated thousands of years ago, but they still consider themselves to be part of a group like their wild ancestors. When there are no other dogs around, their human family becomes their pack. According to Reader's Digest, this genetic instinct is also what motivates dogs to watch you closely and seek out your physical touch.

The second reason for the behavior has to do with the bond between you and your pet. As veterinarian Dr. Rachel Barrack told the American Kennel Club, puppies as old as 6 months can imprint on their human owners like they would their own mothers. Even older dogs will bond with the humans in their lives who show them care and affection. In these cases, a dog will shadow its owner because it sees them as an object of trust and security.

The last possible explanation for why your dog follows you has more to do with your treatment of them than their natural instincts. A popular training tactic is positive reinforcement—i.e. rewarding a dog with treats, pets, and praise when they perform positive behaviors. The point is to help your dog associate good behaviors with rewards, but after a while, they may start to associate your presence with rewards as well. That means if your dog is following you, they may be looking for treats or attention.

A clingy dog may be annoying, but it usually isn't a sign of a larger problem. If anything, it means your dog sees you in a positive light. So enjoy the extra companionship, and don't be afraid to close the door behind when you need some alone time.