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Bending Sticks Into Tools Is Apparently NBD for Crows

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You know how parents think their kid’s first step was the most impressive first step in the history of the world, or that no other child could possibly be as clever? Apparently these love-goggles are not unique to parents. Researchers say they were “completely surprised” to discover that the brilliant behavior of a star subject—a clever crow named Betty—was pretty normal in the wild. They published their report in the journal Royal Society Open Science.

Birds, especially crows, are smarter than we like to admit, but New Caledonian crows (Corvus moneduloides) take it to the next level. These birds have been using tools for so long that their beaks have evolved to make tool-handling easier. They select the best sticks and leaves, trim them neatly with their beaks, and even put them away carefully when they’re finished. They’re totally on top of this twig thing. 

Even so, researchers were boggled in 2002 when they saw Betty, a wild-caught crow, pick up a length of wire in the lab and bend it into a hook shape in order to fish a food bucket out of a tube. 

The bird had seemingly spontaneously invented a new method of tool production. In bending that wire, the authors wrote, Betty demonstrated an extraordinary knowledge of causality and “folk physics” to an extent never before seen in a non-human animal.

But just because we hadn’t seen it doesn’t mean it wasn’t happening. Biologist Christian Rutz and his colleagues at the University of St. Andrews have been studying wild New Caledonian crows for the last four years. They brought 18 crows into large temporary enclosures and gave them puzzles that could only be solved with tools. 

To the researchers’ great surprise, 10 out of the 18 crows bent their twigs into hooks without giving it a second thought. And they didn't do it just once: This group produced 85 hooks in all. It turns out that Betty, who died in 2005, wasn't such a genius after all.

“We couldn’t believe our eyes,” Rutz told New Scientist. “Most birds trapped sticks underfoot before bending the tool shaft by bill, but one also pushed tools against the logs to flex them, and another wedged them upright into holes before pulling the shaft sideways, just as Betty had done.” 

The scientists realized that, in addition to selecting twigs for shape and size, the birds were looking for pliability. Not just any stick would do.

Watching the birds crafting their tools, Rutz said, he and his colleagues were “over the Moon.”

“In light of our new results,” he said, “more experiments are needed to figure out what exactly these birds are capable of.”

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Animals
10 Notable Gestation Periods in the Animal Kingdom
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The gestation periods of the animal kingdom are varied and fascinating. Some clock in at just a few weeks, making any human green with envy, while others can last more than a year. Here are 10 notable gestation times for animals around the globe. The lesson? Be thankful that you’re not a pregnant elephant.

1. ELEPHANTS: 640-660 DAYS

Elephants are pregnant for a long time. Like really, really long. At an average of 95 weeks, the gestation period is more than double the length of a human pregnancy, so it shouldn't come as a shock that female elephants don't often have more than four offspring during their lifetimes. Who has the time?

2. HIPPOS: 8 MONTHS

A photo of a mother hippo and her baby in Uganda

Yes, it takes less time to make a hippopotamus than it takes to make a human.

3. GIRAFFE: 14-15 MONTHS

Baby giraffes can weigh more than 150 pounds and can be around 6 feet tall. Another fascinating tidbit: giraffes give birth standing up, so it's pretty normal for a baby to fall 6 feet to the ground.

4. KILLER WHALE: 17 MONTHS

There’s a reason for the long wait: after that 17 months, Baby Shamu emerges weighing anywhere from 265 to 353 pounds and measuring about 8.5 feet long. Yikes.

5. OPOSSUM: 12-13 DAYS

A baby opossum wrapped up in a blanket

Blink and you'll miss it: This is the shortest gestation period of any mammal in North America. But since the lifespan of an opossum is only two to four years, it makes sense.

6. GERBILS: 25 DAYS

Hey, they get off pretty easy.

7. GORILLAS: 8.5 MONTHS

It's not a huge surprise that their gestational periods are pretty similar to ours, right?

8. BLACK BEAR: 220 DAYS

A pair of black bear cubs

Also less than a human. Interestingly, cubs might only be 6 to 8 inches in length at birth and are completely hairless. 

9. PORCUPINE: 112 DAYS

This is the longest gestation period of any rodent. Thankfully for the mother, porcupine babies (a.k.a. porcupettes) are actually born with soft quills, and it's not until after birth that they harden up.

10. WALRUS: 15 MONTHS

Baby walruses? Kind of adorable. They certainly take their sweet time coming out, though.

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Goldfish Can Get Depressed, Too
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Don’t believe what Pixar is trying to sell you: Fish are not exactly brimming with personality. In aquariums, they tend to swim in circles, sucking up fragments of food and ducking around miniature treasure chests. To a layperson, fish don’t appear to possess concepts of happy, or sad, or anything in between—they just seem to exist.

This, researchers say, is not quite accurate. Speaking with The New York Times, Julian Pittman, a professor at the Department of Biological and Environmental Sciences at Troy University, says that fish not only suffer from depression, they can be easily diagnosed. Zebrafish dropped into a new tank who linger at the bottom are probably sad; those who enthusiastically explore the upper half are not.

In Pittman’s studies, fish depression can be induced by getting them “drunk” on ethanol, then cutting off the supply, resulting in withdrawal. These fish mope around the tank floor until they’re given antidepressants, at which point they begin happily swimming near the surface again.

It’s impossible to correlate fish depression with that of a human, but Pittman believes the symptoms in fish—losing interest in exploring and eating—makes them viable candidates for exploring neuroscience and perhaps drawing conclusions that will be beneficial in the land-dwelling population.

In the meantime, you can help ward off fish blues by keeping them busy—having obstacles to swim through and intriguing areas of a tank to explore. Just like humans, staying active and engaged can boost their mental health.

[h/t The New York Times]

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