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8 Ways Spiders Are Creepily Clever

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You may already know that spiders can spin intricate webs and poison their prey. But that doesn't even begin to cover the all the sneaky abilities spiders have adapted to become the most fearsome organisms on eight legs. Here are some of the tricks spiders use to catch their meals while avoiding becoming dinner themselves.

1. THEY HAVE SUPER-POWERED SENSES.

Spidey-senses weren't just invented for comic books. Jumping spiders in real life have sharp eyesight and excellent hearing to make up for their inability to spin webs. Scientists long assumed that spiders couldn't hear because they don't have ears. But as researchers reported in a 2016 study, jumping spiders can "hear" perfectly fine—they just use the super sensitive hairs on their legs to do so. These same spiders can also see surprisingly well, as astronomer Jamie Lomax demonstrated when she used laser pointers to lure them away from her desk like they were tiny cats.

2. THEY MIMIC ANTS.

The fact that the jumping spider species Myrmarachne formicaria tricks predators into thinking it's an ant by mimicking its appearance isn't a new discovery. But exactly how it achieves this was unclear until recently. According to a Harvard study published in the Proceedings of the Royal Society B, the spider pulls off this deceptive stunt while using all eight legs to walk. During its performance, it takes 100-millisecond pauses to lift its front two limbs to its head so they resemble antennae. The switch is so fast that to a human looking from above, the spider appears to simply be walking with its back six legs while lifting its front legs off the ground. Scientists had to use high-speed cameras to prove this wasn't the case. 

3. THEY TUNE THEIR WEBS.

Despite lacking ears, spiders have some impressive musical talents. They treat the strands of their webs like the strings of a guitar, tuning them just right so they can detect certain vibrations. For their study published in the Journal of the Royal Society Interface, researchers from the University of Oxford and Charles III University of Madrid observed garden cross spiders maintaining their webs. They learned that adjusting the tension and stiffness of the silk allows the spiders to sense frequencies they can recognize. One signal might mean that prey is near, while another could be connected to structural issues with the web.

4. THEY PRETEND TO BE BIRD POOP.

Spider disguised as bird poop.

Min-Hui Liu et. al, Scientific Reports // CC BY-NC-ND 3.0

Camouflage is not unique among arachnids, but orb weaver spiders may win the prize for the most memorable disguise. In its juvenile stage of life, the spider will surround itself with a thick, white material in the center of its web. Its whitish abdomen blends into the "decoration," making the spider appear as if it's buried in a splatter of bird droppings. The unappetizing look is usually enough to convince predators to look elsewhere for a meal that's easier to stomach.

5. THEY CAST NETS.

Spider with web between it's legs.

Chen-Pan Liao, Wikimedia Commons // CC BY-SA 3.0

Bigger isn't always better when it comes to webs. Take the net-casting spider: The silken trap it uses to snare food is small enough to fit between its limbs. The spider poops out a pale "target" onto the forest floor and then hangs above it waiting, sometimes for hours, for an insect to come along and trigger a "trip wire" connected to the ground. Once that moment comes, it wastes no time lunging at its prey and enveloping it in its web. It then bites and paralyzes its prey before commencing the feast.

6. THEY CAN FIRE THEIR HAIRS LIKE TINY BARBED SPEARS.

If all else fails, at least tarantulas have their spear-like hairs to fall back on. A tarantula deploys its "urticating hairs" when it feels threatened. By grinding its back legs against its abdomen, it's able to shoot the barbed hairs at its target like a shower of tiny throwing stars. You don't have to be a predator to trigger this defense mechanism, as many tarantula pet owners have found out the hard way.

7. THEY SOMERSAULT.

When most spiders need to escape a dangerous situation, they rely on their eight limbs to scurry them to safety. The golden wheel spider curls up its body and rolls down hills to make an even speedier getaway. This type of spider is native to the Namib Desert in southern Africa, where steep, sandy dunes are abundant. When it's tucked into a ball, the spider can reach tumbling speeds of 3.2 feet per second.

8. THEY CREATE BUBBLE SUBMARINES AND SCUBA SUITS.

Even without gills, spiders have adapted some pretty clever ways of surviving underwater for long amounts of time. The diving bell spider weaves web balloons that extract dissolved oxygen from the water around it while filtering out carbon dioxide. Using this improvised scuba suit, the spider can last a whole day before it needs to come up for air. Then there are wolf spiders, which use a much more dramatic survival tactic. A 2009 study found that marsh-dwelling varieties of wolf spiders appear to drown after being submerged for extended periods. But once they're placed on dry land, they twitch back to life. Slipping into a coma underwater is how they're able to evade death.

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Feeling Down? Lifting Weights Can Lift Your Mood, Too
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There’s plenty of research that suggests that exercise can be an effective treatment for depression. In some cases of depression, in fact—particularly less-severe ones—scientists have found that exercise can be as effective as antidepressants, which don’t work for everyone and can come with some annoying side effects. Previous studies have largely concentrated on aerobic exercise, like running, but new research shows that weight lifting can be a useful depression treatment, too.

The study in JAMA Psychiatry, led by sports scientists at the University of Limerick in Ireland, examined the results of 33 previous clinical trials that analyzed a total of 1877 participants. It found that resistance training—lifting weights, using resistance bands, doing push ups, and any other exercises targeted at strengthening muscles rather than increasing heart rate—significantly reduced symptoms of depression.

This held true regardless of how healthy people were overall, how much of the exercises they were assigned to do, or how much stronger they got as a result. While the effect wasn’t as strong in blinded trials—where the assessors don’t know who is in the control group and who isn’t, as is the case in higher-quality studies—it was still notable. According to first author Brett Gordon, these trials showed a medium effect, while others showed a large effect, but both were statistically significant.

The studies in the paper all looked at the effects of these training regimes on people with mild to moderate depression, and the results might not translate to people with severe depression. Unfortunately, many of the studies analyzed didn’t include information on whether or not the patients were taking antidepressants, so the researchers weren’t able to determine what role medications might play in this. However, Gordon tells Mental Floss in an email that “the available evidence supports that [resistance training] may be an effective alternative and/or adjuvant therapy for depressive symptoms that could be prescribed on its own and/or in conjunction with other depression treatments,” like therapy or medication.

There haven’t been a lot of studies yet comparing whether aerobic exercise or resistance training might be better at alleviating depressive symptoms, and future research might tackle that question. Even if one does turn out to be better than the other, though, it seems that just getting to the gym can make a big difference.

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Uncombable Hair Syndrome Is a Real—and Very Rare—Genetic Condition
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Everyone has bad hair days from time to time, but for roughly 100 people around the world, unmanageable hair is an actual medical condition.

Uncombable hair syndrome, also known as spun glass hair syndrome, is a rare condition caused by a genetic mutation that affects the formation and shape of hair shafts, BuzzFeed reports. People with the condition tend to have dry, unruly hair that can't be combed flat. It grows slower than normal and is typically silver, blond, or straw-colored. For some people, the symptoms disappear with age.

A diagram of a hair follicle
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Although there have been only about 100 documented cases worldwide, one of the world's leading researchers on the condition, Regina Betz, of Germany's University of Bonn, believes there could be thousands of others who have it but have not been diagnosed. Some have speculated that Einstein had the condition, but without a genetic test, it's impossible to know for sure.

An 18-month-old American girl named Taylor McGowan is one of the few people with this syndrome. Her parents sent blood samples to Betz to see if they were carriers of the gene mutation, and the results came back positive for variations of PADI3, one of three genes responsible for the syndrome. According to IFL Science, the condition is recessive, meaning that it "only presents when individuals receive mutant gene copies from both parents." Hence it's so uncommon.

Taylor's parents have embraced their daughter's unique 'do, creating a Facebook page called Baby Einstein 2.0 to share Taylor's story and educate others about the condition.

"It's what makes her look ever so special, just like Albert Einstein," Taylor's mom, Cara, says in a video uploaded to YouTube by SWNS TV. "We wanted to share her story with the world in hopes of spreading awareness."

[h/t BuzzFeed]

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