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10 Huge Facts About Whale Sharks 

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The Ellen Show, YouTube

This fascinating, filter-feeding species will finally get its close-up in this summer's Finding Dory. Here are a few things you might not have known about the world's largest fish.

1. THE BIGGEST ARE ABOUT 40 FEET LONG.

It’s often said that the whale shark’s maximum length from end to end is about 45 feet, but this is a fish story. The longest verified measurements of live (or recently dead) specimens are in the 40-foot range. 

How heavy can they get? That’s a difficult question to answer. Weighing such huge marine animals is no easy task; many scientists simply estimate instead. Still, researchers at the Okinawa Churaumi Aquarium have managed to weigh several individuals over the years. The heaviest they’ve encountered was a captured 30-footer that weighed just above 7 tons. In the wild, longer ones probably weigh a good deal more.

2. MOTHERS GIVE BIRTH TO LIVE YOUNG.

For years, there was much debate over how baby whale sharks come into the world. Then, in 1995, a pregnant female was fatally harpooned near Taiwan. An autopsy revealed that her uteri (all sharks have two) contained around 300 unborn embryos. This discovery confirmed that the species is ovoviviparous. In other words, whale sharks—like certain snakes—hatch from eggs that are stored inside their mother’s body. Afterward, the little fish exit her womb fully-formed.

3. WHALE SHARKS GROW UP FAST.

Thirty or 40-foot adult whale sharks have few natural enemies. Juveniles, on the other hand, are easy pickings for predators like blue sharks and marlins. These youngsters have every incentive to get big quick—which is exactly what they do.

Consider this: In just three years and 68 days, one newborn whale shark at Japan’s Oita Ecological Aquarium went from weighing 1.7 to 333.4 pounds. Another infant showed the astonishing growth rate of 18 inches per year over 630 days.

But, like human babies, young whale sharks don’t keep growing at the same speed forever. Once the fish reach a certain size, scientists theorize that their growth rate slows down considerably. By then, the creatures have—again, in theory—become big enough to scare away would-be attackers. 

4. THEY’VE GOT THOUSANDS OF TEETH.

Most sharks have 20 to 30 rows of pearly whites, but whale sharks have more than 300 rows. That means a whale shark has 3000 individual teeth, each one about the size of a match head.

5. WHALE SHARKS CAN FEED VIA SUCTION.

All those teeth don't do very much, though. Despite their enormous size, whale sharks exclusively dine on very small life forms like plankton, krill, fish eggs, and small fish. The sharks usually swallow their food whole. Attached to the gills is a mesh-like network of long, cartilaginous bars known as “gill rakers.” These allow water to escape, but prevent even millimeter-sized victims from doing so. Eventually, the meal is forced down our whale shark’s narrow throat and digested.

Sometimes, a whale shark will lazily swim with its mouth agape. This low-energy feeding technique allows the beast to passively swallow any food items that might be in its path. But when it sees a dense cluster of potential targets, the shark changes tactics: The animal creates suction by rapidly opening and closing its jaws, pulling dinner into its cavernous maw. Here’s a look at this second method in action:

6. THEY’RE MIGRATORY. 

Generally, whale sharks—which are tropical and sub-tropical fish—are encountered from latitudes 30° N to 35° S. Within this range, they move around a lot: In three years, a single whale shark can travel 8000 miles or more. Though scientists don’t fully understand their migration habits, we know that the fish tend to gather en masse in specific places at specific times. For example, huge schools visit exotic locales like the Galapagos Islands and Yucatan Peninsula every summer to gorge on plankton.

7. PARTS OF THEIR SKIN ARE INCREDIBLY TOUGH.

Covered in hard, tooth-like scales called denticles, the hide on a whale shark's back can be up to 4 inches thick. Whale sharks can toughen this skin still further by clenching the muscles that lie just beneath it. Conversely, their underbellies are relatively soft and vulnerable—so when approached by human divers, a whale shark will often turn its belly away from them.  

8. WE DON’T KNOW HOW OLD THEY CAN GET.

Most experts agree that whale sharks reach sexual maturity around age 30, but their total life expectancy is unknown—and estimates are all over the map. According to some ichthyologists, the big fish probably die in their sixties. Others speculate that whale sharks can live to be 100 or even 150 years old. For the record, scientists aren’t completely sure about the great white shark’s maximum lifespan either—though they’re now known to reach age 70 or more.

9. WHALE SHARKS ARE LIABLE TO JOURNEY FAR BELOW THE SURFACE.

In 2003 and 2004, a team led by biologist S.G. Wilson studied the long-term movements of six different whale sharks near western Australia. According to their results, the sharks mostly avoid deep plunges—in fact, the surveyed animals spent over half of their time within 100 feet of the surface.

With that said, though, whale sharks occasionally travel much, much further down. One of the Wilson team’s specimens, for instance, spent at least 12 uninterrupted hours at a depth of 3215 feet. And this wasn’t an isolated incident—tagged whale sharks off the coasts of India have been recorded hitting 2200- to 3200-foot depths as well. Why do the fish embark on such extreme dives? Nobody knows, although the answer likely has something to do with either keeping cool or gathering food.

10. NASA (INDIRECTLY) HELPED PERFECT A WHALE SHARK TRACKING SERVICE.

No two whale sharks share the exact same pattern. Just behind their gills, every single one has a totally unique arrangement of pale, white spots. Today, this fun fact is helping biologists keep tabs on individual sharks—with some help from a secret weapon inspired by NASA. 

Mapping out stars can be a daunting task. The Groth algorithm, created in 1986, is a pattern-recognition formula that enables NASA scientists to identify the countless star fields observed by instruments like the Hubble Telescope.

Decades later, one conservationist group is using a new version of this for a very different purpose. ECOCEAN is an Australian non-profit that runs the largest whale shark identification program on earth—and anybody with a camera can participate. The concept is simple. If you’ve ever filmed or photographed a wild whale shark, send ECOCEAN a copy of your footage—along with some basic details about when and where the encounter occurred.

Then, a modified Groth algorithm is used to figure out if your fish is one of the 13,000-plus individuals on their record. If a match is pinpointed, you’ll get an email with a summary of that particular shark’s migration history.

Jason Holmberg of Portland, Oregon is ECOCEAN’s information architect. During the early 2000s, he worked with NASA astrophysicist Zaven Arzoumanian to develop this new fish-centered Groth algorithm. As Holmberg explained, their final product closely resembles the original. “We just adapted that from [identifying] white spots on a black night sky to white spots on the flank of a whale shark,” he told National Geographic

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Animals
25 Shelter Dogs Who Made It Big
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Focus Features

If you’ve been thinking of adding a four-legged friend to your brood and are deciding whether a shelter dog is right for you, consider this: Some of history’s most amazing pooches—from four-legged movie stars to heroic rescue dogs—were found in animal shelters. In honor of Adopt-a-Shelter-Dog Month, here are 25 shelter dogs who made it big.

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This High-Tech Material Can Change Shape Like an Octopus
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iStock

Octopuses can do some pretty amazing things with their skin, like “see” light, resist the pull of their own sticky suction cups, and blend in seamlessly with their surroundings. That last part now has the U.S. Army interested, as Co.Design reports. The military branch’s research office has funded the development a new type of morphing material that works like an octopus’s dynamic skin.

The skin of an octopus is covered in small, muscular bumps called papillae that allow them to change textures in a fraction of a second. Using this mechanism, octopuses can mimic coral, rocks, and even other animals. The new government-funded research—conducted by scientists at Cornell University—produced a device that works using a similar principle.

“Technologies that use stretchable materials are increasingly important, yet we are unable to control how they stretch with much more sophistication than inflating balloons,” the scientists write in their study, recently published in the journal Science. “Nature, however, demonstrates remarkable control of stretchable surfaces.”

The membrane of the stretchy, silicone material lays flat most of the time, but when it’s inflated with air, it can morph to form almost any 3D shape. So far, the technology has been used to imitate rocks and plants.

You can see the synthetic skin transform from a two-dimensional pad to 3D models of objects in the video below:

It’s easy to see how this feature could be used in military gear. A soldier’s suit made from material like this could theoretically provide custom camouflage for any environment in an instant. Like a lot of military technology, it could also be useful in civilian life down the road. Co.Design writer Jesus Diaz brings up examples like buttons that appear on a car's dashboard only when you need them, or a mixing bowl that rises from the surface of the kitchen counter while you're cooking.

Even if we can mimic the camouflage capabilities of cephalopods, though, other impressive superpowers, like controlling thousands of powerful suction cups or squeezing through spaces the size of a cherry tomato, are still the sole domain of the octopus. For now.

[h/t Co.Design]

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