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jude via Flickr Creative Commons // CC BY 2.0
jude via Flickr Creative Commons // CC BY 2.0

Wild Elephants May Get the Least Sleep of Any Mammal

jude via Flickr Creative Commons // CC BY 2.0
jude via Flickr Creative Commons // CC BY 2.0

Sleep is a funny thing. We literally can’t live without it, yet there’s still a lot about it that we just don’t understand. Now, new insight into the unconscious hours of African elephants may muddle the matter further, as a study in the journal PLOS One finds that the massive beasts spend barely any time asleep at all.

Scientists have hypothesized that the size of a mammal’s body is negatively associated with the amount of time it spends sleeping; in other words, big animals sleep less than small ones. Current record holders for shortest sleep time are the domestic horse (two hours, 53 minutes) and pony (three hours, 20 minutes).

While generally accepted, the theory has been tough to test, since you can’t exactly invite a whale into the laboratory for an overnight sleep study. Many studies have focused on captive animals for this reason, but there’s often a big difference between the lives of animals in zoos and those roaming free.

To check in on the sleeping habits of the wild African elephant (Loxodonta africana), researchers focused on the middle-aged matriarchs of two different herds. The scientists fitted each elephant with a collar to monitor her location and body position. (Elephants have two sleeping positions: lying down, which allows for deep REM sleep, and standing up, which is more of a shallow-sleep, nap-type situation.) They also implanted a small movement tracker at the tip of her trunk. Then both elephants were released to go about their lives as usual. The researchers took the trackers back 35 days later and reviewed the data they’d collected.

As it turns out, the elephants had been living remarkably busy lives. Like high-powered businesspeople, they rarely lay down—just once every three or four nights. The rest they did get—mostly while standing—was shallow and brief, averaging about two hours per night. Some nights they just kept walking and never slept at all.

“Studies of sleep in captive elephants have shown that they sleep for four to six hours per day,” study co-author Paul Manger of the University of the Witwatersrand said in a press statement. “However, the current study shows that in their natural habitat, wild, free-ranging elephants sleep only for two hours per day, the least amount of sleep of any mammal studied to date.”

What this means for elephants and other mammals remains to be seen. With just two participants, this was a very small study, and the researchers only tracked movement, not sleep itself. One of the two elephants was also caring for a calf, a responsibility that likely cut into her sleeping time.

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Pigeons Are Secretly Brilliant Birds That Understand Space and Time, Study Finds
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Of all the birds in the world, the pigeon draws the most ire. Despite their reputation as brainless “rats with wings,” though, they’re actually pretty brilliant (and beautiful) animals. A new study adds more evidence that the family of birds known as pigeons are some of the smartest birds around, as Quartz alerts us.

In addition to being able to distinguish English vocabulary from nonsense words, spot cancer, and tell a Monet from a Picasso, pigeons can understand abstract concepts like space and time, according to the new study published in Current Biology. Their brains just do it in a slightly different way than humans’ do.

Researchers at the University of Iowa set up an experiment where they showed pigeons a computer screen featuring a static horizontal line. The birds were supposed to evaluate the length of the line (either 6 centimeters or 24 centimeters) or the amount of time they saw it (either 2 or 8 seconds). The birds perceived "the longer lines to have longer duration, and lines longer in duration to also be longer in length," according to a press release. This suggests that the concepts are processed in the same region of the brain—as they are in the brains of humans and other primates.

But that abstract thinking doesn’t occur in the same way in bird brains as it does in ours. In humans, perceiving space and time is linked to a region of the brain called the parietal cortex, which the pigeon brains lack entirely. So their brains have to have some other way of processing the concepts.

The study didn’t determine how, exactly, pigeons achieve this cognitive feat, but it’s clear that some other aspect of the central nervous system must be controlling it. That also opens up the possibility that other non-mammal animals can perceive space and time, too, expanding how we think of other animals’ cognitive capabilities.

[h/t Quartz]

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The Queen's Racing Pigeons Are in Danger, Due to an Increase in Peregrine Falcons
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Queen Elizabeth is famous for her love of corgis and horses, but her pet pigeons don't get as much press. The monarch owns nearly 200 racing pigeons, which she houses in a luxury loft at her country estate, Sandringham House, in Norfolk, England. But thanks to a recent boom in the region’s peregrine falcon population, the Queen’s swift birds may no longer be able to safely soar around the countryside, according to The Telegraph.

Once endangered, recent conservation efforts have boosted the peregrine falcon’s numbers. In certain parts of England, like Norfolk and the city of Salisbury in Wiltshire, the creatures can even find shelter inside boxes installed at local churches and cathedrals, which are designed to protect potential eggs.

There’s just one problem: Peregrine falcons are birds of prey, and local pigeon racers claim these nesting nooks are located along racing routes. Due to this unfortunate coincidence, some pigeons are failing to return to their owners.

Pigeon racing enthusiasts are upset, but Richard Salt of Salisbury Cathedral says it's simply a case of nature taking its course. "It's all just part of the natural process,” Salt told The Telegraph. "The peregrines came here on their own account—we didn't put a sign out saying 'room for peregrines to let.' Obviously we feel quite sorry for the pigeons, but the peregrines would be there anyway."

In the meantime, the Queen might want to keep a close eye on her birds (or hire someone who will), or consider taking advantage of Sandringham House's vast open spaces for a little indoor fly-time.

[h/t The Telegraph]

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