Why do we smell different when we’re sick? Why does cheese smell like feet? Why don’t vultures get sick from eating rotting meat? Science is filled with stories: some of them are beautiful and some of them are gross. Really gross. Gross Science, a YouTube series hosted by Anna Rothschild, tells bizarre stories from the slimy, smelly, creepy world of science. In this collection, you’ll find original short-form videos and DIY experiments from Gross Science, which is produced by NOVA and PBS Digital Studios.

The series answers questions like....

Why don't vultures get food poisoning? In this episode, students learn how vultures eat rotting meat without getting sick. Vultures are meat-eating scavengers; instead of hunting prey, they wait for carcasses left behind from other hunters. Their incredibly acidic stomachs help kill the pathogens in the rotting meat. Additionally, the intestines of vultures are colonized by species of bacteria that are related to disease-causing ones typically found on rotting meat, which gives vultures a natural tolerance to the bacteria. However, vultures aren’t immune to everything. Certain medications given to livestock are poisonous to vultures.

How far do sneezes and vomit travel? Learn how far coughs, sneezes, and vomit travel, in this episode of Gross Science. Scientists can use technology to track the liquids that fly out of noses and mouths and study how far germs can travel. Researchers at MIT used high-speed cameras to reveal that the droplets in a cough or sneeze travel in an invisible gas cloud, which can carry germs much farther than people previously thought. Researchers use robots to simulate the act of puking to study the spread of norovirus. One episode of projectile vomiting can contaminate close to 84 square feet, and virus particles can also be suspended in the air. This research reveals that germs are easily spread and may linger in places that appear to be clean.

What lives in cheese? Learn about the mites, bacteria, and fungi that make cheese delicious, in this episode. Cheeses come in many different forms, but most are made of the same handful of ingredients: milk, salt, a combination of enzymes called “rennet,” and bacteria. Mixing in bacteria allows milk to ferment, and creates a diversity of flavors and textures in cheese. Cheese makers can also create other varieties by adding fungus, mites, and maggots to the mix. Many other foods, such as bread, wine, yogurt, and pickles, are created in similar ways. They are made by letting other organisms, like yeast and bacteria, digest parts of the food before humans do.



Students can also learn about amphibians that eat their mother’s skin, strange uses for bacon, how poop can be used to cure an infection, and many more gross science topics!