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When Poachers Kill Their Mothers, Elephant Daughters Hold Social Networks Together

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In elephant families, it’s the matriarchs who call the shots. They decide where a group goes, where it eats and when. They’re also the glue that holds elephant societies together. Elephants have a tiered social network of small “core groups” of close relatives, and larger, less cohesive “bond groups” and “clan groups” that include distant relatives and acquaintances. Older matriarchs with lots of social ties are the hubs that connect all these groups to each other. 

These older female leaders are also frequent targets for ivory poachers because of their large tusks. When they’re killed, other elephants not only lose their mothers, sisters, and grandmothers, but also their links to the rest of their social networks. 

In other animal societies, studies have shown that removing individuals who act as social hubs can collapse such networks. With demand for ivory leading to tens of thousands of elephant deaths a year, researchers feared that the same thing would happen to elephants. A new study published in the journal Current Biology shows, though, that elephant societies are more resilient than expected because younger females step into their mothers’ connective roles in the social network. 

Biologists Shifra Goldenberg, Iain Douglas Hamilton, and George Wittemyer explored how elephant networks respond to the “selective knockouts” caused by poaching by looking at data they had collected while studying more than 100 elephants over the last 18 years in Kenya’s Samburu National Reserve. They knew many of the elephants by the shape of their ears, their scars and other body markings, and even their behavioral quirks. They also knew which elephants hung out together and how their different groups were connected. 

The researchers went back to their observations and reconstructed the Samburu elephants’ social network at different points between 1998 and 2014, during which there were stretches of relatively little poaching and a recent period of intense poaching. 

They found that over those 16 years, the average age of the Samburu elephants became much younger as older elephants were killed. There was a high turnover in the population’s adult females, and less than one-third of the elephants that the researchers encountered in 1998 were still alive last year.

Despite the death toll, the Samburu social network didn’t fall apart. It remained intact because daughter elephants stepped in to fill the roles that were left behind by their mothers. In some of these cases, the new matriarchs were barely fully grown, but their surviving relatives still rallied around them as the oldest females in the family.

These younger elephants not only took over the leadership of their core groups, but filled in the connective roles in the bigger network, often replicating the positions held by their mothers. Daughters maintained the social ties and relationships their mothers had built when they were alive, keeping their core group connected to the others in the bond group through matriarchs that their mothers had known, or their daughters if both moms had died. This helped them to keep the network intact with more or less the same structure that had existed before. When daughters couldn’t recreate their mothers’ networks exactly, they used the social opportunities that their mothers had provided them to strengthen relationships with elephants that were once only distant contacts of their moms, thus creating new bond groups.

The resilience of the elephants’ social structure is good news, but the researchers warn that there’s more work to be done before we know all the consequences of these families losing their oldest members. Even with the leadership roles filled and social ties maintained, elephants groups may run into problems with younger matriarchs in the lead. They lack the experience and knowledge that their mothers accrued over time, and other research has shown that older matriarchs are better than younger ones at distinguishing and responding to predators and other threats, and that families with older leaders have higher reproductive rates. The researchers plan to keep monitoring the Samburu elephants to see how these rebuilt families fare over 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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