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David M. Jensen via Wikimedia Commons // CC BY-SA 3.0
David M. Jensen via Wikimedia Commons // CC BY-SA 3.0

Capuchin Monkeys Can Be Spiteful Jerks, Study Finds

David M. Jensen via Wikimedia Commons // CC BY-SA 3.0
David M. Jensen via Wikimedia Commons // CC BY-SA 3.0

Humanity’s throne atop the animal kingdom is wobbling these days. Research has shown that non-human animals can make complex tools, give gifts to their friends, and even read complicated medical images. But it can’t all be good news. Some of humanity’s less desirable traits have parallels in our non-human relatives. In fact, a recent study published in Evolution and Human Behavior shows that capuchin monkeys share our capacity for acting spiteful.

We’ve all seen animals behaving in ways we could interpret as spiteful. But scientists have argued that there’s really no way to understand the motivations of, say, a dog that chews up your socks, because there are just too many variables at play.

So scientists designed an experiment that would allow them to test for spite and spite alone. “One hallmark of the human species is the fact that we’re willing to make a special effort to punish those who violate social norms,” senior author Laurie Santos said in a press statement. “We punish those who take resources unfairly and those who intend to do mean things to others. Many researchers have wondered whether this motivation is unique to our species.”

Capuchin monkeys (Cebus apella) are carefully attuned to one another’s behavior. Previous experiments with C. apella have shown that capuchins pay attention to how fairly or evenly resources are distributed—that is, if another monkey got more of something. When they have to complete a group task, capuchins tend to avoid teaming up with monkeys who have a track record of being uncooperative or selfish. 

To complete the research, the researchers first set up collapsible tables attached to long ropes. Then, they gave the monkeys some time to learn how the rope-table setup worked. When the scientists were sure the monkeys understood the consequences of pulling the rope, the capuchins were divided into two groups: subjects and stooges.

During each test, the researchers sat one stooge monkey at the table and gave control of the rope to a subject monkey. Then the food came out. It was good food, too—Fruity Pebbles cereal (which the researchers describe as “a highly valued food reward”) and marshmallow fluff. The stakes were high.

There was no mistaking the intentions of these monkeys. Time and time again, subject monkeys would yank the rope to collapse the stooges’ table and make the food disappear. This was true even when the stooges had done nothing to get the food; in other words, the subjects punished them for getting food even when they were innocent.

“Our study provides the first evidence of a non-human primate choosing to punish others simply because they have more,” first author Kristin Leimgruber, said in the press release. “This sort of ‘if I can't have it, no one can’ response is consistent with psychological spite, a behavior previously believed unique to humans.”

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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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