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Networking is an important professional skill. Building relationships with people who are really successful or well-informed can help you succeed, too.

And that is true whether you’re a person or apparently, a lemur, according to new research published this week in Current Biology. Researchers from Princeton wanted to look at whether social position affected how lemurs navigate challenges. So they came up with a puzzle for lemurs to solve: a clear Plexiglass box with a drawer containing a single tasty grape, which ensured that only the lemur who solved the box got the treat.

Two groups of about 20 lemurs each were allowed to interact with each other and with the box over multiple sessions while the researchers recorded what happened. Based on previous studies, they expected that well-connected lemurs would be more likely to solve the puzzle. And that’s exactly what they saw—lemurs who already had more social connections within the group were more likely to get the grape, perhaps because their extra relationships provided more opportunities to observe and learn as their friends messed with the box.

But the researchers were surprised to find that the reverse was true, too. No matter what their status was beforehand, lemurs who figured out the box in front of their peers became more popular. Other individuals starting to approach and groom the grape-getters more often, regardless of age or sex, even though these clever lemurs didn’t groom them back.

The scientists behind the study think that’s because the other lemurs saw the potential benefits of being connected to the smarty-pants lemurs. Buddying up to them could increase their opportunities to learn from them in the future. This is the first time it’s been shown that learning ability alone can influence an animal’s position in its social network, and it’s a reminder of how closely intertwined cognitive abilities and social behavior can be.

Lemurs are after grapes, humans are after that next great career opportunity -- but for all of us primates, networking is essential. Meanwhile, for amphibians, rubbing elbows can be a death sentence. And some researchers are trying to figure out how to save them.

Frogs and salamanders have been spreading something not so great through their social networks. It’s called Chytrid. Chytridiomycosis, better known as chytrid, is a mysterious fungal disease that has devastated amphibian populations around the world.

It infects the skin of frogs and salamanders, impairing their ability to breathe and absorb moisture. And in the past three decades, it’s nearly or completely wiped out almost 200 frog species, mostly in the tropics. With so much on the line, researchers are eager to figure out how best to fight it.

And a new study is giving them hope: in certain areas where the disease hit hard, like Panama, some species of frogs seem to be bouncing back. Hopping back..? That’s often how epidemics go.

For even the most dangerous diseases, there usually comes a point where there’s a shift from a widespread, deadly outbreak to a period where hosts and pathogens come to coexist. I mean, like, bubonic plague is still around, but it doesn’t routinely wipe out half the population of Europe. But we don’t always know whether that transition happens because the pathogen becomes less virulent, or because it wipes out the most susceptible hosts, leaving behind the more resistant survivors.

And understanding how the recovering frog species are managing to survive the fungus could help scientists win the battle for more susceptible species. Luckily, researchers were able to catch the Panama transition in action, because they began studying frog populations before the height of the epidemic there. The fungus expanded into Panama between 2004 and 2007.

But, after 5-13 years, nine out of the twelve amphibian species the scientists were tracking showed some signs of recovery, even though chytrid was still around. To understand how these animals were making their comeback, the researchers exposed a population of captive frogs to fungal samples collected during different points in the outbreak. Their results, published last week in the journal Science, show that the fungus remains just as devastating, even more than a decade after it arrived.

But, skin secretions collected from wild frogs that survived the epidemic were better at slowing the growth of the fungus than secretions from the same species captured before the disease hit. So the recovery seen in some wild frog populations is probably because they evolved to become more resistant as a group, most likely because frogs that happened to have some innate ability to fight off the disease survived and reproduced. If frogs’ ability to adapt to the disease sounds like good news, it is.

It’s a sign that at least some affected species may gradually recover on their own. But it could also mean unexpected challenges for one of the strategies for saving frog populations devastated by chytrid -- captive breeding. Most current breeding efforts started off with animals captured before the disease hit.

And that means the frogs we’re releasing may be more susceptible to chytrid than the frogs that remain, so by introducing them, researchers could make the frog populations as a whole less resistant. Two steps forward, one step back -- that’s often how it seems to go in the world of conservation biology. But now, at least would-be frog rescuers know to keep an eye out for problems like this as they move forward with their efforts to save species.

And whether you’re figuring out how to get a step ahead of the epidemic affecting frogs, or trying to get a grape out of a puzzle box to impress your friends, you need your brain working in top condition. Brilliant.org has a whole course on logic puzzles that will really stretch your grey matter! So now we’re here to do that brain stretching and we’ve got some perfect information logic puzzles.

And the idea here is that everybody is infinitely intelligent and everyone knows that everyone else in this situation is infinitely intelligent. Alice and Bob are both given a different positive one digit number excluding zero. They make the following statements in order.

Alice, “I don’t know whose number is bigger.” Bob, “I don’t know whose number is bigger.” Alice, “I don’t know whose number is bigger.” Bob, “I don’t know whose number is bigger.” What is Bob’s number? So Alice says, “I don’t know whose number is bigger.” So her number can’t be 1 or 9, because then she would know. Bob says, “I don’t know whose number is bigger.” So he knows that her number isn’t 1 or 9 and he still doesn’t know, so his number can’t be 3 or 7, because those are the only options I have to choose from.

So that means it’s 5. Brilliant.org stretching my brain out! It’s fun and I feel like I’m smarter than I thought I was.

That’s always a good feeling. And, hey, if you want to stretch your brain out, there’s logic puzzles but there is also a lot of other information that you can gain from Brilliant.org. And the first 77 people that sign up at Brilliant.org/SciShow will get 20% off their annual subscription and you’ll also be helping out SciShow.

So thanks for checking it out! Stretchy brain. [ ♪ Outro ].