5

Sharks Get Paralyzed If You Put Them Upside-Down

Sharks are deadly and majestic creatures, killing machines so perfect that they haven't changed in millions of years. Truly the peak of evolution. Unless you put them on their backs. Then they're goofy and helpless.

That video shows a diver controlling and lifting a shark as if it was a cheerleading competition. Just rub their nose a little and put them upside-down, and the mightiest predator in the ocean turns into a more pathetic version of the Super Bowl sharks.

4

Bamboo-Induced Diarrhea Is Destroying Pandas

About 2 million years ago, pandas switched to an all-plant diet, probably in a failed attempt to shed those adorable extra pounds. Unfortunately, their digestive systems still haven't adapted to the change, which means they keep getting deadly cases of the shits.

Everything else about pandas is adapted to eating bamboo: stronger jaws to chew on it, "thumbs" for ripping it apart, etc. But not their stomachs, which you'd think would be the first thing evolution would tackle. Like other (carnivorous) bears, pandas digest food in less than ten hours, but herbivores usually need 24 hours or more. This means pandas have to spend all day eating to gain the same amount of energy from their food. This in turn gives them diarrhea. And not the regular Taco Bell type of diarrhea; they get a weird kind with mucus. Here's an adorable video to take your mind off that mental image:

3

There's A Horny Lemur With Gigantic, Perpetually Sore Balls

The northern giant mouse lemur, or Mirza zaza, is about the size of a common squirrel, with one notable exception. They have the largest known testicles in the primate world, relatively speaking.

"Ladies."

According to the scientists who found them, if humans had the same relative size balls, we would be walking around with two grapefruits in our pants. Which means these poor lemurs are constantly hitting them against every tree and branch in the jungle. Ugh, yeah, we've been there. It's not fun.

Now, we know what you're thinking: Don't lemur balls change size depending on the breeding season and available food? Yes, you weirdo. But not for these guys. Unlike other lemurs, the Mirza zaza's testicles stay big all year round. They don't have a specific breeding season, which means this little fellow is always horny. They live in a perpetual state of testicular soreness and blue balls. Life just keeps kicking them in the nuts, both literally and figuratively.

2

Sloths Can Die Of Starvation On A Full Stomach

Sloths are famously slow, and we mean that in every conceivable way. They can't regulate their body temperature, so in order to stay cool and function, they have to burn very little energy, giving them the lowest metabolic rate of any non-hibernating mammal. Yes, even their internal organs are a bunch of lazy bastards. In practical terms, this means that they take something like 50 days to do a single dump. Wow, that's ... that's a lot of Cracked articles. We take it back. We love you, sloths.

Since sloths only eat plants that aren't very nutritious (they're too lazy to read the value charts), they don't get a lot of energy. They've developed a whole system of gut bacteria to help them deal with that junk food, but since they can't regulate their body temperature, they sometimes get too cold if the temperature drops. If this happens, the bacteria inside the sloth will die, and they won't be able to digest the food. At all.

1

Tarsiers Smash Their Heads Open When They Get Stressed

Tarsiers look like they were specifically designed to be as adorable as possible. They are essentially a whole species of anime-eyed Baby Yodas. That's why it's unfortunate that 1) They get very stressed around humans, and 2) They tend to freak out and kill themselves violently when they get stressed. Merely touching one once is enough to put them into Gruesome Suicide Mode.

Jasper Greek Golanco/Wikimedia CommonsDid you say "Aww"? Congratulations, you just killed it.