10 Ginormous Facts About Coconut Crabs

Janos/iStock via Getty Images
Janos/iStock via Getty Images

They're huge and antisocial. They will steal your silverware and can rip apart whole coconuts with their claws. Grab a piña colada and enjoy these 10 ginormous facts about the amazing coconut crab.

1. Coconut crabs are colossal.

Native to islands in the Indian and southern Pacific oceans, are truly humongous. They can weigh 9 pounds and measure 3 feet from leg to leg. Coconut crabs are the largest land-living arthropods—the phylum of joint-legged creatures that includes crabs, insects, spiders, and scorpions. Even Charles Darwin was stunned by their “monstrous size.”

But be aware: Occasionally, a viral photo circulates that exaggerates the coconut crab’s size. As biologist Michael Bok explains, the coconut crab in that infamous photo is normal sized, but the trash can is unusually small.

2. Coconut crabs are actually hermit crabs.

Sandwich, Flickr // CC BY-NC-ND 2.0

Where does such a bizarre animal fit in the animal kingdom? Are they lobsters? Tarantulas? Space aliens? In fact, Birgus latro is a kind of hermit crab.

You may have seen smaller hermit crabs on a trip to the beach—or for sale at a pet shop. They take shelter inside abandoned snail shells, carrying them around as portable homes. But if coconut crabs are hermit crabs, then why don’t they live in shells? Well, they do—when they’re young and still small.

3. Coconut crabs quickly outgrow their borrowed shells.

Like other crabs, hatchling coconut crabs begin their lives floating freely at sea. After about a month of eating and growing, they find a snail shell and move in. The little coconut crabs carry this mobile home as they begin to transition to a land-based life.

A seashell is a nice, protected place to live, but it has its drawbacks [PDF]. As a crab gets bigger, its shell gets tighter—like an old pair of shoes on a kid who’s growing fast. The crab needs to find a bigger shell and make a quick switch. And that larger home will be heavier to tote around.

So, after a year or so of inhabiting shells, the coconut crab makes a major lifestyle change. It crawls out and hardens the parts of its body that were once protected by the shell by regrowing layers of calcium-based tissues, a process called recalcification. Without its old home, it’s free of size constraints. Now, unlike other hermit crabs, it can become enormous.

4. Coconut crabs eat coconuts, of course ...

This might seem obvious from the coconut crab’s name. But if you’ve ever tried to crack open a coconut, you know that it’s a steep challenge. In fact, a lengthy scientific debate once raged about whether coconut crabs were really able to open the fruit. It turns out that they’re up to the challenge—but they don’t just pop open their prize and dig in.

Breaking into a coconut is a mighty ordeal even if you’re a heavily armored crustacean the size of a small dog. Coconut crabs first use their claws to scrape away the fibrous coating. This can take hours or days. Finally, they stab into the fruit at a weak point and rip it open.

This diet helps coconut crabs grow large: those with access to coconuts may be twice as massive as those without. But eating the fruit isn’t essential for their survival. So what other items do the largest land-living arthropods shove into their maw?

5. ... but they also eat dead animals, their own body parts, and each other.

As well as the occasional biscuit, as you can see in the video above. (Note: Do not feed biscuits to coconut crabs.) A coconut crab’s diet may include other tropical fruits, fallen plant material, dead and decaying animals, rats, and other crab species. They’ll even eat members of their own kind. In fact, biologist Mark Laidre says they only relatively recently evolved to eat coconuts—a skill unique to modern coconut crabs—which helps them to eat each other less.

They also eat their own discarded body parts. As coconut crabs grow, they periodically molt their tough outer layer (the exoskeleton) and grow a new one. Once they’re done molting, which takes about a month, they gobble up their own exoskeleton.

6. Coconut crabs have an amazing sense of smell ...

Coconut crabs often forage at night. How do they find food when they’re wandering around in the dark? They sniff it out. These animals have a strong, highly efficient [PDF] sense of smell. In fact, a large portion of their brain is devoted to detecting odors.

7. ... which might explain why they're thieves.

Coconut crabs are also known as robber crabs because they snatch silverware and other objects and carry them away. Some people have even advanced the gruesome theory that Amelia Earhart’s remains are missing because coconut crabs hauled them down into their burrows. The thievery might be tied to that incredible sense of smell. Coconut crabs ignore objects that have been washed clean of scents, suggesting that they may only abscond with things that carry a faint whiff of food.

8. Coconut crabs are pretty antisocial.

Adult coconut crabs live alone in crevices or burrows. They aggressively guard their privacy; a crab entering another’s burrow risks becoming a meal.

But that’s not the end of their antisocial behavior. When coconut crabs emerge to feed, they keep their distance from each other. To maintain their personal space, they’ll announce their presence with ritualized claw waving. Laidre sought to find out if coconut crabs ever gathered together to interact (beyond mating or eating each other). The scientist tethered coconut crabs to one spot and watched to see if any others came to visit. They did not.

9. Coconut crabs carry their developing young under their abdomens.

After coconut crabs mate, females attach their eggs to special appendages and carry them under their abdomens. While the young develop inside the eggs, the females hold onto them, sticking near the edge of the sea so that they can periodically moisten the eggs.

But this care ends when the young are ready to hatch. The females release their hatchlings into the ocean waves. Now the tiny, floating babies must fend for themselves—and only a few will survive to return to land.

10. We need to learn a lot more about coconut crabs.

Anne Sheppard, Wikimedia Commons // CC BY 3.0

Coconut crabs are little-studied creatures, and we need to know more about them—not just because they’re incredible and have a lot to tell us about biology, but also because we want to keep them around.

They may be huge and heavily armored, but they can be vulnerable. Coconut crabs take an extremely long time to grow big—they can live more than 40 years—and introduced predators such as rats can harm smaller, younger individuals or those in the process of shedding their exoskeletons (when their bodies are soft). Habitat loss has also caused local declines in some areas. The International Union for Conservation of Nature lists the coconut crab as data deficient: That is, we don’t know enough about its locations and populations. That’s why we need to study and learn more about these amazing, otherworldly critters.

The 10 Best Air Fryers on Amazon

Cosori/Amazon
Cosori/Amazon

When it comes to making food that’s delicious, quick, and easy, you can’t go wrong with an air fryer. They require only a fraction of the oil that traditional fryers do, so you get that same delicious, crispy texture of the fried foods you love while avoiding the extra calories and fat you don’t.

But with so many air fryers out there, it can be tough to choose the one that’ll work best for you. To make your life easier—and get you closer to that tasty piece of fried chicken—we’ve put together a list of some of Amazon’s top-rated air frying gadgets. Each of the products below has at least a 4.5-star rating and over 1200 user reviews, so you can stop dreaming about the perfect dinner and start eating it instead.

1. Ultrean Air Fryer; $76

Ultrean/Amazon

Around 84 percent of reviewers awarded the Ultrean Air Fryer five stars on Amazon, making it one of the most popular models on the site. This 4.2-quart oven doesn't just fry, either—it also grills, roasts, and bakes via its innovative rapid air technology heating system. It's available in four different colors (red, light blue, black, and white), making it the perfect accent piece for any kitchen.

Buy it: Amazon

2. Cosori Air Fryer; $120

Cosori/Amazon

This highly celebrated air fryer from Cosori will quickly become your favorite sous chef. With 11 one-touch presets for frying favorites, like bacon, veggies, and fries, you can take the guesswork out of cooking and let the Cosori do the work instead. One reviewer who “absolutely hates cooking” said, after using it, “I'm actually excited to cook for the first time ever.” You’ll feel the same way!

Buy it: Amazon

3. Innsky Air Fryer; $90

Innsky/Amazon

With its streamlined design and the ability to cook with little to no oil, the Innsky air fryer will make you feel like the picture of elegance as you chow down on a piece of fried shrimp. You can set a timer on the fryer so it starts cooking when you want it to, and it automatically shuts off when the cooking time is done (a great safety feature for chefs who get easily distracted).

Buy it: Amazon

4. Secura Air Fryer; $62

Secura/Amazon

This air fryer from Secura uses a combination of heating techniques—hot air and high-speed air circulation—for fast and easy food prep. And, as one reviewer remarked, with an extra-large 4.2-quart basket “[it’s] good for feeding a crowd, which makes it a great option for large families.” This fryer even comes with a toaster rack and skewers, making it a great addition to a neighborhood barbecue or family glamping trip.

Buy it: Amazon

5. Chefman Turbo Fry; $60

Chefman/Amazon

For those of you really looking to cut back, the Chefman Turbo Fry uses 98 percent less oil than traditional fryers, according to the manufacturer. And with its two-in-one tank basket that allows you to cook multiple items at the same time, you can finally stop using so many pots and pans when you’re making dinner.

Buy it: Amazon

6. Ninja Air Fryer; $100

Ninja/Amazon

The Ninja Air Fryer is a multipurpose gadget that allows you to do far more than crisp up your favorite foods. This air fryer’s one-touch control panel lets you air fry, roast, reheat, or even dehydrate meats, fruits, and veggies, whether your ingredients are fresh or frozen. And the simple interface means that you're only a couple buttons away from a homemade dinner.

Buy it: Amazon

7. Instant Pot Air Fryer + Electronic Pressure Cooker; $180

Instant Pot/Amazon

Enjoy all the perks of an Instant Pot—the ability to serve as a pressure cooker, slow cooker, yogurt maker, and more—with a lid that turns the whole thing into an air fryer as well. The multi-level fryer basket has a broiling tray to ensure even crisping throughout, and it’s big enough to cook a meal for up to eight. If you’re more into a traditional air fryer, check out Instant Pot’s new Instant Vortex Pro ($140) air fryer, which gives you the ability to bake, proof, toast, and more.

Buy it: Amazon

8. Omorc Habor Air Fryer; $100

Omorc Habor/Amazon

With a 5.8-quart capacity, this air fryer from Omorc Habor is larger than most, giving you the flexibility of cooking dinner for two or a spread for a party. To give you a clearer picture of the size, its square fryer basket, built to maximize cooking capacity, can handle a five-pound chicken (or all the fries you could possibly eat). Plus, with a non-stick coating and dishwasher-safe basket and frying pot, this handy appliance practically cleans itself.

Buy it: Amazon

9. Dash Deluxe Air Fryer; $100

Dash/Amazon

Dash’s air fryer might look retro, but its high-tech cooking ability is anything but. Its generously sized frying basket can fry up to two pounds of French fries or two dozen wings, and its cool touch handle makes it easy (and safe) to use. And if you're still stumped on what to actually cook once you get your Dash fryer, you'll get a free recipe guide in the box filled with tips and tricks to get the most out of your meal.

Buy it: Amazon

10. Bella Air Fryer; $52

Bella/Amazon

This petite air fryer from Bella may be on the smaller side, but it still packs a powerful punch. Its 2.6-quart frying basket makes it an ideal choice for couples or smaller families—all you have to do is set the temperature and timer, and throw your food inside. Once the meal is ready, its indicator light will ding to let you know that it’s time to eat.

Buy it: Amazon

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A Two-Toed Sloth Accidentally Hitched a 40-Mile Ride in a Truck's Engine Bay

Tony Hisgett, Wikimedia Commons // CC BY 2.0
Tony Hisgett, Wikimedia Commons // CC BY 2.0

Most sloths move at a maximum speed of 6 to 8 feet per minute, but one two-toed sloth in Costa Rica shattered that pace on a recent joy ride. As Jalopnik reports, the female sloth traveled 40 miles after sneaking into a truck’s engine bay undetected.

The vehicle's drivers noticed something was out of place when they stopped to check the engine and saw a tuft a fur. They reached out to Toucan Rescue Ranch, a wildlife rehabilitation center near San Jose, which identified the stowaway as a two-toed sloth. Though it had been on board for over an hour, the animal managed to survive the road trip unscathed.

The animal caretakers at TRR dubbed the sloth Lola la Trailera, or "Lola the Truck Driver," after the 1983 Mexican action movie of the same name. She was exhausted and aggressive when she arrived at the center, but after feeding her a diet of Pedialyte, wild leaves, and steamed veggies, the caretakers were able to restore her to full health. She was returned to the forest she originated from following six days of rehabilitation.

A sloth's usual lack of speed isn't a sign of laziness—it's a survival tactic. Fat and protein are limited in the rainforest canopies where sloths reside, so they must conserve energy by limiting their activity. But as Lola la Trailera proved, sloths have the potential to move much faster with a little assistance.

[h/t Jalopnik]