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Cuckolded Sparrow Fathers Stop Feeding Their Kids

“Predictably Philandering Females Prompt Poor Paternal Provisioning”—that’s the name of a recent report on infidelity in house sparrows. The paper was published in The American Naturalist.

Monogamy means different things to different people—and different animals. House sparrows mate for life, yet years of observation of birds in the wild suggest that they’re also pretty prone to sleeping around. An international team of researchers had a lot of questions about how this works. Are house sparrows really that promiscuous, and, if so, does such behavior pay off? How do the mates of cheating sparrows respond? And how does that affect their kids?

To find out, the researchers set up shop on Lundy Island, an itsy-bitsy spot in the UK’s Bristol Channel. They caught, tagged, and took tiny tissue samples from 200 male birds and 194 females, then released the birds and watched the avian soap opera unfold. Tiny implanted trackers made it possible to tell which bird was which, and when that bird had entered his or her nest.

"Lundy is a unique natural laboratory because it is almost a closed system,” said lead author and Imperial College of London biologist Julia Schroeder in a press statement. “Very few birds leave the island or arrive from the mainland. In the entire 12 years, only four birds immigrated to Lundy, possibly carried by boat."

During that same period, the birds formed 313 pairs and produced 863 broods of baby birds. DNA tests of the birds’ tissue samples, and those of their babies, allowed the researchers to see quite plainly which sparrows were dallying outside their partnerships. A lot of them, it turns out: 38 percent of the broods included offspring from outside partners. Nearly all the couples stayed together once they had bonded, but both male and female birds cheated on their partners.

When those results were matched to video of the sparrows’ behavior, a trend emerged: Cuckolded male sparrows stopped tending to their chicks. This is a big deal for sparrows, a species that depends on care from both parents.

How could the male sparrows tell when their partners had strayed? It wasn’t from looking at the chicks and thinking, “Hey, wait a minute.” The researchers tested this by swapping out a couple’s chicks when they weren’t looking. Dad sparrows couldn’t tell which chicks were theirs, and treated all the little ones interchangeably.

"If chicks were switched into a nest where the female was faithful, then the father at that nest kept up his hard work providing for the chicks, suggesting they have no mechanism, such as smell, to determine which chicks are theirs," Schroeder said.

Instead, the birds are likely relying on context clues. As in: If your mate is going out a lot, and not with you, something might be up. “The males may use cues from the female’s behavior during her fertile period,” Schroeder said, “for example, how long she spends away from the nest.”

Here’s the thing: Animals don’t just sleep around for no reason. Some earlier studies had theorized that cheating might help female sparrows bring fresh genetic material into their nests while maintaining the social stability of a partnership. But if a cuckolded dad starts starving his kids, what’s the benefit?

There may not be one, the researchers say. It’s possible that the sparrows’ cheating hearts are just an evolutionary holdover from the days before the species became monogamous. Or, rather, “monogamous.”

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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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