Why Do Dogs Eat Poop?

<div class="rich-text"><h3>
 The Chemistry of Skunk Spray
</h3>

 Posted: October 13, 2016


 Why do skunks smell so bad? It all comes down to chemistry.


 By the way, this video will include slow motion footage of skunk anuses. So, be warned.


 I’m Anna Rothschild, and this is Gross Science.


 There are a number of species of skunk in the world, but the most iconic has to be the striped skunk. That’s the one that looks like Pepe Le Pew—it’s all black, typically with one white line that usually splits into two on its back. And it can be found all over the United States as well as northern Mexico and southern Canada. Its latin name is
 
 Mephitis mephitis
 
 , which appropriately enough means something like foul stench or noxious vapor.


 Obviously, that’s because the most defining character of skunks is their defensive spray, which can cause watery eyes, nausea, and leave you smelling terrible. The chemical makeup of the spray is different depending on the species, but all of them contain special types of compounds called “thiols.” Thiols, also known as “mercaptans,” are a type of chemical group made up of a sulfur and hydrogen atom bonded together. And they typically smell really strongly.


 There are actually three different thiols in striped skunks spray, and two of those are the main contributors to the awful odor. But three other molecules in the spray are what are called “thioacetates.” Those compounds don’t have a strong scent, but they can easily become thiols when they’re exposed to water. And that might explain why a pet that gets sprayed may start to smell skunky again after a bath.


 Now, skunk musk is produced by anal scent glands—which actually, lots of mammals have, though most aren’t quite this exciting. When a skunk sprays, nipple-like protrusions called papillae come out of the anus and squirt the musk at the target. The bad news is they can squirt a distance of about 10 feet, and are uncannily good at hitting their mark. The good news is that skunks really don’t want to spray unless they have to, and adults usually give warning signals beforehand. Striped skunks will hiss, stomp, and raise their tails before spraying. And spotted skunks will even do a handstand.


 But, what should you do on the off-chance that you wind up covered in musk? Well, definitely don’t use tomato juice—that’s just a myth. Instead, use something that converts the thiol into a different type of compound. Some scientists suggest using a mixture of dilute hydrogen peroxide, baking soda, and a little liquid soap, which will oxidize the thiol and turn it into a sulfonic acid. But be careful, because it could dye your hair or pet fur.


 Anyway, despite their terrible reputation, some skunks have actually been domesticated, and people say they make really cute and affectionate pets. But if you do want a pet skunk, make sure you know how to take care of it and get one from a breeder. Grabbing one from the woods is not at all nice for the skunk. And it would probably let you know that by squirting you with an anal gland full of noxious musk.


 Ew.

</div>

Koch Foundation

NOVA Science Trust Logo

United States

Northern Mariana Islands

Puerto Rico

American Samoa

Guam

U.S. Virgin Islands

U.S. Minor Outlying Islands

US & Territories

NOVA investigates the story of cannabis from the criminalization that has disproportionately harmed communities of color to the latest medical understanding of the plant. What risks does cannabis pose to the developing brain? How much do we know about its potential medical benefits? As cannabis becomes socially accepted, scientists are exploring its long-term health consequences. (Premiered September 29, 2021)Check out a previously recorded panel discussion and audience Q&amp;A featuring experts and producers from "The Cannabis Question" <a href="https://youtu.be/nSTT5RZ_hxA">here</a>.

As state-legalized cannabis spreads, NOVA explores its little-known risks and benefits.

The Cannabis Question

A 2006 composite image from NASA's Hubble Space Telescope and Spitzer Telescope shows the chaos of baby stars in the Orion nebula some 1,500 light-years away. Image Credit: NASA/JPL-Caltech/STScI

With the upcoming launch of the James Webb Space Telescope, the Hubble era is gradually drawing to a close. Here are some highlights from the countless wonders Hubble has shown us during its 31 years in space.

10 spectacular Hubble Space Telescope images

A statue of Zheng He at the Sam Poo Kong Temple in Java, Indonesia. Image Credit: Budianto Santosa, Shutterstock

In the 1400s, Zheng He sailed thousands of miles around Asia and Africa in ships the size of soccer fields, spreading Chinese innovations like compasses and gunpowder in the process.

Transcript

Credits

Sources

Support Provided By