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Monkeys Have Been Using Tools for 700 Years

Jane Goodall’s discovery of chimpanzee tool use in 1960 came as a shock to her contemporaries, who believed that our ability to make and wield instruments set us above other animals. Since that time, we’ve gradually learned that lots of animals, from birds to insects, make and use tools. Some of them have been at it for a long, long time: Archaeologists have found that Brazilian capuchin monkeys have been using hammers to crack nuts for at least 700 years. That makes their stone hammers and anvils the oldest non-human tools known outside of Africa, the researchers write in a report they published this week in the journal Current Biology.

Image credit: Michael Haslam/Primate Archaeology Project

The bearded capuchin (Sapajus libidinosus) is a nimble little monkey found in the forests of northeast Brazil. S. libidinosus is not a particularly picky eater, and will happily chow down on flowers, fruit, leaves, bugs, frogs, small mammals, and baby birds. But scientists are most interested in the monkey’s taste for cashews. For the love of cashews, the bearded capuchin has learned to wield a small stone like a hammer, smashing the nut’s tough shell open on an anvil-like large stone. The monkey will then leave the tools in a pile by the cashew tree for next time. Hammer, crack, eat, repeat.

Archaeologists suspected that the capuchins had been repeating for a long, long time. To find out just how long, they used hand trowels to excavate the soil under four popular modern-day nut-smashing sites. They didn’t have to look very far to find what they were looking for; digging just 0.7 meters (2.29 feet) down yielded 69 different cashew-smashing implements.

The tools were surprisingly easy to identify. They looked exactly like the same stones preferred by today’s monkeys, and many of the rocks were smudged with cashew resin (a fact confirmed by chemical testing). And just like today’s monkey tools, most of the unearthed hammers were made of hard, smooth quartzite, while the anvils were flat sandstone.

The dig had also unearthed little pieces of charcoal. By carbon dating those pieces, the team could estimate the age of the stones nearby. They found that the stones could be sorted into three time periods. The stones near the top had been used quite recently. Those in the second layer dated from about 1614–1958, and the bottom layer went all the way back to the year 1266.

Project leader Michael Haslam is an archaeologist at the University of Oxford. “This is an exciting, unexplored area of scientific study that may even tell us about the possible influence of monkeys' tool use on human behavior,” he said in a press statement. “It is possible that the first humans to arrive here learned about this unknown food through watching the monkeys and their primate cashew-processing industry.”

Studying monkey behavior has been quite a shift for Haslam, who’s spent most of his career looking at artifacts and remains. The live animals are a lot more unpredictable, he notes in the video above: “They have their own lives going on. Sometimes you’ll see them beginning to do something really interesting with their tools, and then another monkey comes running in and there’s a big fight, or they have to leave for some reason, or they just fall asleep.” 

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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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