11 Surprisingly Smart Birds

ThinkStock
ThinkStock

Next time someone tries to put you down by calling you "bird brain," make them think again by introducing them to these 11 wickedly smart avians.

1. Cormorants Make Model Employees

A researcher in the 1970s observed the behavior of cormorants that Chinese fishermen used to catch fish. The birds were only fed after catching seven fish for their human masters, and once they hit that magic number, they would sit pat and refuse to continue working. The cormorants had learned to count to seven, and they used this to their advantage in their unique salary negotiations.

2. Japanese Crows Enjoy Street Food

In urban parts of Japan, crows have been known to drop shelled nuts onto crosswalks for cars to run over, cracking their shells. The birds then wait for red lights before retrieving the exposed meat.

3. Macaws Take Direction Well

Macaws can correctly tell the difference between left and right when trained with positive reinforcement.

4. Crows Never Have to Eat Crow

Crows aren’t the most glamorous birds, but biologists have dubbed them "feathered primates" for their tremendous brainpower and problem-solving skills. In one study, crows were able to memorize and correctly identify images they had been previously shown. When researchers switched the rules of the game to reward the birds for identifying images that didn’t match, they quickly adjusted and answered correctly mid-test.

5. Ravens Are Excellent Meat Cutters

After chasing a raven that was feeding on a piece of frozen raw beef, a researcher found that the bird had made cuts tracing the fat, allowing it to carry the food as one large chunk instead of making multiple trips. This ingenuity showed the raven was able to plan ahead.

6. Blue Tits Skim the Cream

Back when milk was delivered door-to-door, these birds were able to identify what kinds were being delivered based on the colors of the bottle caps. They learned which bottles contained extra-nourishing whole milk, and the birds then breached and drank from those containers.

7. Hummingbirds Know Their Turf

While these speedsters are tiny—they weigh less than a nickel—they make up for it with their massive memories. A hummingbird keeps tabs on every flower in its territory (which can contain up to 1000 different flowers) and remembers which ones are blooming and which ones have nectar.

8. Rooks Can Be The Bigger Bird

Rooks live in large groups and are prone to getting in fights. After squabbles, the birds make up by preening each other or sharing food. The first observations of this behavior surprised biologists, since for years scientists had thought that only primates were capable of this kind of reconciliatory behavior.

9. Pigeons Appreciate Fine Art

In a now-famous study, three researchers discovered that pigeons were able to differentiate between paintings by Picasso and Monet (although they could not tell the difference if the Monets were placed upside-down).

10. Cockatoos Can Cut a Rug

A famous cockatoo has demonstrated the ability to recognize complex musical beats and dance along in time (which requires an intelligent skill known as “beat induction”).

11. Woodpecker Finches Arm Themselves

These birds from the Galapagos Islands have been known to use sticks to impale grubs and other small invertebrates. Once incapacitated, the prey is easily devoured by the weapon-wielding finch.

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.

Coconut crab
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.

Coconut crab
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.

‘Water’ in Kansas City Woman’s Ear Turned Out to Be a Venomous Brown Recluse Spider

N-sky/iStock via Getty Images
N-sky/iStock via Getty Images

Susie Torres, a resident of Kansas City, Missouri, woke up on Tuesday morning with the distinct feeling that water was lodged in her left ear. She likened it to the swooshing sensation that can often happen after swimming, WDAF-TV reports.

Instead of waiting for the problem to resolve itself, Torres went to the doctor—a decision that might have saved her from some serious pain. The medical assistant was the first to realize something was alarmingly amiss, and immediately called for backup.

“She ran out and said ‘I’m going to get a couple more people,’” Torres told 41 Action News. “She then said, ‘I think you have an insect in there.’” For many people, the thought of having any live insect stuck in an ear would be enough to cue a small- or large-scale freak-out, but Torres stayed calm.

The doctors “had a few tools and worked their magic and got it out,” Torres said. The “it” in question turned out to be a spider—and not just any harmless house spider (which you shouldn’t kill, by the way). It was a venomous brown recluse spider.

“Gross,” Torres told WDAF-TV. “Why, where, what, and how.”

Miraculously, the spider didn’t bite Torres. If it had, she would’ve ended up visiting the doctor with more than general ear discomfort: Brown recluse bites can cause pain, burning, fever, nausea, and purple or blue discoloration of the surrounding skin, according to Healthline.

Torres may have remained admirably level-headed throughout the ordeal, but that doesn’t mean she’s taking it lightly. “I went and put some cotton balls in my ears last night,” she told WDAF-TV. “I’m shaking off my clothes, and I don’t put my purse on the floor. I’m a little more cautious.”

Is this the first time an insect has posted up in the ear of an unsuspecting, innocent human? Absolutely not—here are six more horror stories, featuring a cockroach, a bed bug, and more.

[h/t WDAF-TV]

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