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Wirepec // iStock
Wirepec // iStock

10 of the World's Strangest Spiders

Wirepec // iStock
Wirepec // iStock

All spiders have eight legs, but that’s where most of their similarities end. Scientists frequently discover new species with unexpected talents—be it a flair for cartwheels or the ability to turn itself into a disco ball. Researchers have also found plenty of specimens that are just plain weird-looking. Here’s a list of 10 fascinatingly freaky arachnids.

1. CEBRENNUS RECHENBERGI // THE FLIC-FLAC SPIDER

A native of the Erg Chebbi desert in southeastern Morocco, Cebrennus rechenbergi—also known as the flic-flac spider—has the remarkable ability to cartwheel its way out of danger. When threatened by a predator, it will leap off the ground and do a series of high-energy somersaults to make a quick exit. An alarmed flic-flac spider can tumble forward at a rate of 6.6 feet per second—twice as fast as its maximum walking speed. If pressed, it can even cartwheel uphill. Such talents did not go unappreciated by this spider’s discoverer, bionics expert Ingo Rechenberg, who has built a somersaulting robot based on the flic-flac’s locomotion.

2. BAGHEERA KIPLINGI // A JUMPING SPIDER

Bagheera kiplingi spider
Maximilian Paradiz // Wikimeda Commons // CC BY 2.0

Those who have read Rudyard Kipling’s The Jungle Book may have already figured out that this species was named after the panther who helps raise Mowgli. But its pop culture connection is not Bagheera kiplingi’s only claim to fame. It has a plant-based diet, unlike nearly all other spiders, which subsist predominantly on meat. B. kiplingi feasts on the nutritious nubs of Central American acacias, which the trees produce to feed their colonies of guard ants. The ants protect the trees from predators, but the spiders have learned how to swoop in and steal the nubs without providing any symbiotic benefit. The spiders will also eat nectar and ant larvae, and when times are tough, they’ve been known to practice cannibalism.

3. ARACHNURA HIGGINSI // THE SCORPION-TAILED SPIDER

Arachnura higginsi spider
Peter Woodard // Wikimedia Commons // Public Domain

Two phobias for the price of one! Found only in Australia, the scorpion-tailed spider is so named because adult females have a long, thin appendage on the tip of their abdomens. (Males and juveniles lack this structure.) The females can arch this bendable tail over their backsides, which gives them the appearance of irate scorpions and prompts would-be attackers to keep their distance. But it’s all an act: The tail cannot sting and Arachnura higginsi is mostly harmless to humans.

4. CAEROSTRIS DARWINI // DARWIN’S BARK SPIDER

The male Darwin’s bark spider is eager to please. Really, really eager. The diminutive males exhibit what some scientists have called “a rich sexual repertoire” to their much larger mates. During sex, males nibble on their partners’ genitals or immobilize them with a web of silk before getting busy. Males will also detach their own sexual organs inside their mates to prevent females from mating with others. Researchers muse that this unusual behavior grew out of males’ survival instinct: A female Darwin’s bark spider is liable to eat her partner after mating.

5. GENUS SCYTODES // SPITTING SPIDERS

Scytodes thoracica spider
Fritz Geller-Grimm // Wikimedia Commons // CC BY-SA 3.0

Using webs to catch prey is all well and good, but it almost seems tame compared to what spitting spiders do to their victims. To subdue a target, the killers take aim and fire twin streams of venom-drenched silk out of their fangs. At a top speed of 62 miles per hour, the fibers move in a wide-arced, zig-zag pattern. In addition to being coated with poison, this silk drips with a super-sticky glue. Once victims are enmeshed, the glue-covered fibers will shrink, constricting the unfortunate prey. Eventually, the spitting spider will administer a venomous bite and put the trapped entrée out of its misery.

6. GENUS DOLOMEDES // FISHING SPIDERS

Hydrophobic coats and a knack for exploiting surface tension allow these predators to walk on water. Fishing spiders lurk in North America, Europe, Australia, and New Zealand. To hunt tadpoles, aquatic insects, and even small fish, many species of fishing spiders will splay themselves over the surface of freshwater lakes or streams. Then, using hundreds of ultra-sensitive leg hairs, they monitor aquatic vibrations. When prey swims by, the spider homes in on its precise location and dives for the victim, sometimes as much as 18 centimeters below the water’s surface.

7. CYRTARACHNE INAEQUALIS // A “DISCO SPIDER”

This little fellow—which arachnologist Joseph Koh believes is Cyrtarachne inaequalis, a member of the Cyrtarachne orb-weaver spider genus—made a vivid impression on photographer Nicky Bay, who captured its singular light show on film. The orb-weaver’s abdomen exhibits a pulsating movement that appear to show its internal organs working under a translucent membrane, Bay writes. Scientists have suggested that the spiders’ display attracts prey or scares off predators, but how and why C. inaequalis puts on its tiny disco act remains a mystery.

8. GENUS MYRMARACHNE // ANT-MIMICKING JUMPING SPIDERS

Myrmarachne ant spider

Found in tropical and temperate zones all over the world, Myrmarachne spiders pretend to be ants—which predators view as aggressive and not worth the effort—to stay alive. With their elongated heads and hourglass-shaped thoraxes, the arachnids look a lot like various ant species (their Latin name even means “ant-spider”). To help sell the illusion, they’ll wiggle their front legs like an ant’s writhing antennae. Of course, a good actor knows when to break character. If certain Myrmarachne species come across predators that eat ants, they’ll drop the ruse.

9. SUPERFAMILY PALPIMANOIDEA // ASSASSIN SPIDERS

Assassin spiders are so named because most of them eat smaller, sometimes poisonous spiders. To keep their food from biting back, Palpimanoidea have evolved long, skinny, giraffe-like necks. Their tiny heads sport huge sets of jaws. When an assassin spider finds a meal, those jaws impale the target and swing forward at a 90-degree angle. That keeps victims a safe distance away from any of the assassin spider’s sensitive body parts. Before long, the skewered prey will die on one of the distended jaws. Then the feasting can begin.

10. GENUS SELENOPS // SPIDERS THAT GLIDE

Our planet is home to more than 40,000 different kinds of spiders, and luckily for arachnophobes, none of them can fly. But at least one genus can free-fall like champion parachutists. In a 2015 study, biologists documented this unusual behavior by systematically dropping 59 tree-dwelling spiders of the genus Selenops from “either canopy platforms or tree crowns in Panama and Peru.” Ninety-three percent of these arachnids steered themselves towards nearby trees to land safely on the trunks. The researchers speculate that such gliding descents happen all the time in nature. After all, the spiders predominantly reside in trees—and the ability to parachute from one trunk to the next would be a huge asset.

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NOAA, Wikimedia Commons // Public Domain
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Animals
Watch the First-Ever Footage of a Baby Dumbo Octopus
NOAA, Wikimedia Commons // Public Domain
NOAA, Wikimedia Commons // Public Domain

Dumbo octopuses are named for the elephant-ear-like fins they use to navigate the deep sea, but until recently, when and how they developed those floppy appendages were a mystery. Now, for the first time, researchers have caught a newborn Dumbo octopus on tape. As reported in the journal Current Biology, they discovered that the creatures are equipped with the fins from the moment they hatch.

Study co-author Tim Shank, a researcher at the Woods Hole Oceanographic Institution in Massachusetts, spotted the octopus in 2005. During a research expedition in the North Atlantic, one of the remotely operated vehicles he was working with collected several coral branches with something strange attached to them. It looked like a bunch of sandy-colored golf balls at first, but then he realized it was an egg sac.

He and his fellow researchers eventually classified the hatchling that emerged as a member of the genus Grimpoteuthis. In other words, it was a Dumbo octopus, though they couldn't determine the exact species. But you wouldn't need a biology degree to spot its resemblance to Disney's famous elephant, as you can see in the video below.

The octopus hatched with a set of functional fins that allowed it to swim around and hunt right away, and an MRI scan revealed fully-developed internal organs and a complex nervous system. As the researchers wrote in their study, Dumbo octopuses enter the world as "competent juveniles" ready to jump straight into adult life.

Grimpoteuthis spends its life in the deep ocean, which makes it difficult to study. Scientists hope the newly-reported findings will make it easier to identify Grimpoteuthis eggs and hatchlings for future research.

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Joe Raedle, Getty Images
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Animals
10 Things You Might Not Know About Grizzly Bears
Joe Raedle, Getty Images
Joe Raedle, Getty Images

Ursus arctos horribilis is better known by the more casual term of grizzly bear. These massive, brown-haired predators have a reputation as one of nature’s most formidable killing machines. Standing up to 8 feet tall and weighing 800 pounds, these fierce mammals have captivated—and frightened—humans for centuries. Keep your distance and read up on these facts about their love for munching moths, eating smaller bears, and being polar-curious.

1. THEY’RE ACTUALLY PRETTY LIGHT EATERS.

Grizzlies—more accurately, North American brown bears—are strong enough to make a meal out of whatever they like, including moose, elk, and bison. Despite their reputation for having carnivorous appetites, their diet also consists of nuts, berries, fruits, and leaves. They’ll even eat mice. The gluttony doesn’t kick in until they begin to exhibit hyperphagia, preparing for winter hibernation by chomping down enough food to gain up to three pounds a day.

2. THEY USE “CPR” TO GET AT YOUR FOOD.

A grizzly bear eats fruit in Madrid, Spain
Dani Pozo, AFP/Getty Images

More than 700 grizzlies live in or near Yellowstone National Park, which forces officials to constantly monitor how park visitors and the bears can peacefully co-exist. Because bears rummaging in food containers can lead to unwanted encounters, the park’s Grizzly & Wolf Discovery Center tests trash cans and coolers to see if they’re bear-resistant. (Nothing is truly bear-proof.) Often, a bear will use “CPR,” or jumping on a canister with its front legs, in order to make the lid pop off. Containers that can last at least 60 minutes before being opened can be advertised by their manufacturers as being appropriate for bear-inhabited environments.

3. THEY CAN CLIMB TREES.

It's a myth that grizzlies can't climb trees. Though their weight and long claws make climbing difficult [PDF], and they need support from evenly-spaced branches, grizzlies can travel vertically if they choose to.

4. THEY’LL EAT OTHER BEARS.

Two grizzly bears play in a pool at a zoo in France
Jean-Francois Monier, AFP/Getty Images

In addition to being omnivorous, grizzlies can also be classified as cannibals. They’ve been spotted eating the carcasses of black bears in Canada. Calling it a “bear-eat-bear world,” officials at Banff National Park in Alberta said the grizzlies are “opportunistic” and more than willing to devour black bears—sometimes just one-fifth their size—if the occasion calls for it. And it’s not just black bears: One study on bear eating habits published in 2017 recorded a 10-year-old male eating a 6-year-old female brown bear.

5. THEY LOVE MOTHS.

Although grizzlies enjoy eating many insects, moths are at the top of the menu. Researchers have observed that bears are willing to climb to alpine heights at Montana’s Glacier National Park in order to feast on the flying appetizers. Grizzlies will turn over rocks and spend up to 14 hours in a day devouring in excess of 40,000 moths.

6. A PAIR OF THEM ONCE LIVED ON WHITE HOUSE GROUNDS.

A grizzly bear appears at the Wild Animal Sanctuary in Keenseburg, Colorado
John Moore, Getty Images

In what would be considered an ill-advised decision, explorer Zebulon Pike decided to gift his friend President Thomas Jefferson with two grizzly cubs in 1807. Jefferson reluctantly accepted them and kept them in a cage near the north entrance to the White House, and later re-gifted the cubs to museum operator Charles Willson Peale. Sadly, one of them got shot after getting too aggressive with Peale’s family.

7. THEY CAN RUN FASTER THAN USAIN BOLT.

The bears we see in fiction or lazing about in the wild tend to look cumbersome and slow, as most anything weighing nearly a half-ton would. But in a land race, even Olympic champions would be on the losing end. Grizzlies can reportedly run 35 mph, and sustain speeds of up to 28 mph for two miles, faster than Usain Bolt’s 27.78 miles per hour stride (which he can only sustain for a few seconds).

8. THEY MATE WITH POLAR BEARS.

A grizzly bear is shown swimming at a pool in an Illinois zoo
Scott Olson, Getty Images

In parts of Alaska and Canada where grizzlies and polar bears converge, there are sometimes rare sightings of what observers call “grolar bears” or “pizzlies.” With large heads and light-colored fur, they’re a hybrid superbear birthed from some interspecies mating. Typically, it’s male grizzlies who roam into those territories, finding female polar bears to cozy up with. Researchers believe climate change is one reason the two are getting together.

9. THEY KNOW HOW TO COVER THEIR TRACKS.

When it comes to intellect, grizzlies may not get all the same publicity that birds and whales do, but they’re still pretty clever. The bears can remember hotspots for food even if it’s been 10 years since they last visited the area; some have been observed covering tracks or obscuring themselves with rocks and trees to avoid detection by hunters.

10. THEY’RE NOT OUT OF THE WOODS YET.

A grizzly bear and her cub walk in Yellowstone National Park
Karen Bleier, AFP/Getty Images

For 42 years, grizzlies at Yellowstone occupied the endangered species list. That ended in 2017, when the U.S. Fish and Wildlife Service declared that a rise in numbers—from 150 in the 1970s to more than 700 today—meant that conservation efforts had been successful. But overall, the grizzly population is still struggling: Fewer than 2000 remain in the lower 48 states, down from 50,000 two centuries ago.

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