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Christine Cooper

Burrowing Echidnas Act as Natural Hoes

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Christine Cooper

When we talk about ecosystems, we often talk about the food chain, and the ways in which each plant or animal affects others around it. But we don’t often think about the impacts of each creature on its environment. Case in point: the humble echidna, which, researchers now say, can aerate tons of soil every year in its native Australia. A report on the echidna’s contributions was published in the Journal of Experimental Biology.

The echidna—better known among readers of a certain age as “Sonic the Hedgehog’s friend”—is a strange, strange beast. It’s got spines like a porcupine, uses electrosensing to hunt like a shark, and lays eggs like its cousin, the platypus. To give you some idea of what an echidna looks like in motion, check out these adorable little weirdos at the Columbus Zoo:

It’s not a particularly fast animal, nor is it particularly fierce, and exactly how it spends its time has been something of a mystery. (Cue dramatic music) Until now.

Researchers at three Australian universities have made the short-beaked echidna (Tachyglossus aculeatus) their business. They traveled to the woods east of Perth one summer and tracked down 11 different adult echidnas, videotaping each one as it wandered past. Then they caught them and fitted each one with a radio transmitter, GPS tracker, and accelerometer to trace its movements. Before releasing their test subjects, the researchers held them and wiggled them around a bit to calibrate the accelerometers.

Every one to four days, the researchers followed the radio signal to catch each echidna and download the data from its sensors, which amounted to a little more than an hour of movement data per critter. Then the next year, the team did the same thing all over again in the spring.

The data showed a huge difference in seasonal echidna activity. In the spring, the animals trundled about at a “stately” pace, averaging about 0.3 meters per second. Come summer, when temperatures could reach 90 degrees Fahrenheit, echidna life became equally extreme. The animals spent most of the day staying very, very still, but when they had to move, they “sprinted” between spots, easily doubling their springtime speeds. “They certainly try to avoid really hot temperatures,” said study co-author Christofer Clemente in a statement.

During the team’s tagging trip into the woods, Clemente had noticed lots of little gashes in the ground where the echidnas had gouged out their insect meals and wondered if these dig sites were numerous enough to be changing the landscape. He looked over the data from the echidnas’ trackers and found that the animals spent as much as 10 percent of each day moving earth around. Using this, and what he knew about the echidnas’ digging skills, Clemente calculated that each one could easily move about 200 cubic meters, or more than 7000 cubic feet, per year, about the volume of an Olympic-sized swimming pool.

This is important information not only for the echidnas and their subterranean prey, but also for scientists and conservationists.

“They are probably one of the last really big bioturbators [soil mixers] left in Australia,” Clemente said, “which means that they are really important for the environment."

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Big Questions
Why Do We Dive With Sharks But Not Crocodiles?
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Why do we dive with sharks but not crocodiles?

Eli Rosenberg:

The issue is the assumption that sharks' instincts are stronger and more basic.

There are a couple of reasons swimming with sharks is safer:

1. Most sharks do not like the way people taste. They expect their prey to taste a certain way, like fish/seal, and we do not taste like that. Sharks also do not like the sensation of eating people. Bigger sharks like great whites enjoy prey with a high fat-bone ratio like seals. Smaller sharks enjoy eating fish, which they can gobble in one bite. So, while they might bite us, they pretty quickly decide “That’s not for me” and swim away. There is only one shark that doesn’t really care about humans tasting icky: that shark is our good friend the tiger shark. He is one of the most dangerous species because of his nondiscriminatory taste (he’s called the garbage can of the sea)!

2. Sharks are not animals that enjoy a fight. Our big friend the great white enjoys ambushing seals. This sneak attack is why it sometimes mistakes people for seals or sea turtles. Sharks do not need to fight for food. The vast majority of sharks species are not territorial (some are, like the blacktip and bull). The ones that are territorial tend to be the more aggressive species that are more dangerous to dive with.

3. Sharks attacked about 81 people in 2016, according to the University of Florida. Only four were fatal. Most were surfers.

4. Meanwhile, this is the saltwater crocodile. The saltwater crocodile is not a big, fishy friend, like the shark. He is an opportunistic, aggressive, giant beast.

5. Crocodiles attack hundreds to thousands of people every single year. Depending on the species, one-third to one-half are fatal. You have a better chance of survival if you played Russian roulette.

6. The Death Roll. When a crocodile wants to kill something big, the crocodile grabs it and rolls. This drowns and disorients the victim (you). Here is a PG video of the death roll. (There is also a video on YouTube in which a man stuck his arm into an alligator’s mouth and he death rolled. You don’t want to see what happened.)

7. Remember how the shark doesn’t want to eat you or fight you? This primordial beast will eat you and enjoy it. There is a crocodile dubbed Gustave, who has allegedly killed around 300 people. (I personally believe 300 is a hyped number and the true number might be around 100, but yikes, that’s a lot). Gustave has reportedly killed people for funsies. He’s killed them and gone back to his business. So maybe they won’t even eat you.

8. Sharks are mostly predictable. Crocodiles are completely unpredictable.

9. Are you in the water or by the edge of the water? You are fair game to a crocodile.

10. Crocodiles have been known to hang out together. The friend group that murders together eats together. Basks of crocodiles have even murdered hippopotamuses, the murder river horse. Do you think you don't look like an appetizer?

11. Wow, look at this. This blacktip swims among the beautiful coral, surrounded by crystal clear waters and staggering biodiversity. I want to swim there!

Oh wow, such mud. I can’t say I feel the urge to take a dip. (Thanks to all who pointed this out!)

12. This is not swimming with the crocodiles. More like a 3D aquarium.

This post originally appeared on Quora. Click here to view.

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10 Filling Facts About Turkeys
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Don’t be fooled by their reputation for being thoughtless. These roly-poly birds have a few tricks up their wings.


The turkey is an American bird, so why does it share its name with a country on the other side of the world? Laziness, mostly. Turkish traders had been importing African guinea fowl to Europe for some time when North American explorers started shipping M. gallopavo back to the Old World. The American birds looked kind of like the African “turkey-cocks,” and so Europeans called them “turkeys.” Eventually, the word “turkey” came to describe M. gallopavo exclusively.


By the early 20th century, the combination of overzealous hunting and habitat destruction had dwindled the turkey populations down to 30,000. With the help of conservationists, the turkey made a comeback. The birds are now so numerous that they’ve become a nuisance in some parts of the country.


Like all birds, turkeys don’t have teeth, so they’ve got to enlist some extra help to break down their food. Each swallowed mouthful goes first into a chamber called a proventriculus, which uses stomach acid to start softening the food. From there, food travels to the gizzard, where specialized muscles smash it into smaller pieces.


Turkeys of both sexes purr, whistle, cackle, and yelp, but only the males gobble. A gobble is the male turkey’s version of a lion’s roar, announcing his presence to females and warning his rivals to stay away. To maximize the range of their calls, male turkeys often gobble from the treetops.


Due to their deliciousness, turkeys have a lot of natural predators. As the sun goes down, the turkeys go up—into the trees. They start by flying onto a low branch, then clumsily hop their way upward, branch by branch, until they reach a safe height.


The wattle is the red dangly bit under the turkey’s chin. The red thing on top of the beak is called a snood. Both sexes have those, too, but they’re more functional in male turkeys. Studies have shown that female turkeys prefer mates with longer snoods, which may indicate health and good genes.


Turkey eyes are really, really sharp. On top of that, they’ve got terrific peripheral vision. We humans can only see about 180 degrees, but given the placement of their eyes on the sides of their heads, turkeys can see 270 degrees. They’ve also got way better color vision than we do and can see ultraviolet light.


You wouldn’t guess it by looking at them, but turkeys can really book it when they need to. We already know they’re fast in the air; on land, a running turkey can reach a speed of up to 25 mph—as fast as a charging elephant.


Turkeys can recognize each other by sound, and they can visualize a map of their territory. They can also plan ahead and recognize patterns. In other ways, they’re very, very simple animals. Male turkeys will attack anything that looks remotely like a threat, including their own reflections in windows and car doors.


They might look silly, but a belligerent turkey is no joke. Male turkeys work very hard to impress other turkeys, and what could be more impressive than attacking a bigger animal? Turkey behavior experts advise those who find themselves in close quarters with the big birds to call the police if things get mean. Until the authorities arrive, they say, your best bet is to make yourself as big and imposing as you possibly can.


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