Gold Grows On Eucalyptus Trees, Monkeys Purr Like Cats, Millennials Can't Afford To Drive, And More Surprising Studies

Betcha didn't know that gold grows on trees — as long as you're in Australia, and it's a eucalyptus. Or that the WWF has found 500 new species, including a vegetarian piranha and a purring monkey. Or that carers live a fifth longer than non-carers — oh, and that millennials are officially too poor to get behind the wheel. For a full round-up of all of the weirdest studies published this week, read on...

Gold Actually Does Grow On Trees

Remember when your grandma warned you that money didn't grow on trees? Well, she was half right: dollar bills aren't sprouting from tree trunks, but gold sure is. Turns out that eucalyptus trees, which grow naturally in Australia and have been specially cultured all over the world, hold gold particles in their leaves.

In an Australian research experiment, a group of scientists picked a bunch of eucalyptus leaves and carefully extracted the gold particles, measuring how much gold there was in different areas of the tree. It turns out that the real source of gold is about 35 meters under the tree, which mingles with the eucalyptus trees at root level. Because gold is poisonous to trees, the tree then expels gold in its leaves.

The researchers are hoping that the trees will be able to point them to sources of gold, making the metal easier to track down. Over here, we're just planning on going to Australia, picking a whole lot of leaves and balling them in our hands until some gold comes out.

Image: Flickr/epSos .de

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Apparently Millennials Can't Afford To Drive

Millennials are far less likely to get behind the wheel than previous generations — so it figures them lazy millennials aren't even bothering to get in a car and drive places anymore, right? Maybe not: research from the cheerily named Highway Loss Data Institute indicates that our generation just can't afford to buy and maintain a car.

The unemployment rate for teens alone jumped 11 percent between recession-era 2006 and 2010, and hasn't improved much. Young adults are struggling to find employment as well, and the general upkeep of a car — gas costs; repair bills — is just too costly for this generation, which is depressing. Forbes argues that it's not just unemployment to blame, but — deep breath now — "disproportionate generational joblessness and underemployment, the growing burden of college loans, greater financial dependence on their parents, and general economic stagnation in the United States."

And here I thought we were being green.

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There's No Link Between Depression And Cancer

As if depression wasn't quite bad enough on its own, patients have also had to deal with the long-held accepted wisdom that the stress of depression might be linked to cancer. Now, new research from French college Paris Descartes University has indicated this isn't the case, and that said "link" is bogus.

The study was large-scale, utilizing 14,203 participants over a 15-year period. The subjects were consistently asked to report their general health, mental health, diet, age, occupation, and every other data set you can imagine. After all those years, Lemogne and co couldn't find a single link between depression and any cancer. The lead researcher noted that the apparent myth of a link might have come about from a basic human need to know the cause of things: "People continue to have a psychological need to believe an explanation about life and death." We imagine him to be very wise and existential.

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Yes, Using Your Phone At Lunch Is Annoying

So, you're at a high-powered lunch meeting, and your companion pulls out his iPhone and starts texting. Are you annoyed? Most of the time, yes, according to a new study from USC and Howard University — but men aren't anywhere near as conscious of just how irritating it is as women are. The research found that twice as many women as men believed it inappropriate to start checking one's phone during a "power lunch."

When polled, 59 percent of men said that it was was fine to check for texts and e-mails during a work lunch. Women were far less sure: only a third of them felt that it was OK. And if your phone rings? Half of men thought taking a call was perfectly appropriate, but only 26 percent of women agreed.

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Dogs And Elephants Need To Go To Fat Camp

Bet you didn't know this about America's obesity problem: recent research on America's dog and elephant populations has found that both are struggling to keep the pounds off.

More than half of American dogs are overweight, which makes them more susceptible to a whole host of diseases, and also far less likely to be adopted. (Sob.) Plus, three quarters of America's elephants, which is to say captive zoo elephants, are overweight as well. Two-thirds also exhibit signs of stress in their everyday behavior, which has led to some animal-rights group calling for them to be re-instated in their national habitat.

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Being A Caregiver Helps You Live Longer

Wanna live 18 percent longer than everyone else you know? Course you do, but the solution might surprise you: according to new research from the University of Alabama at Birmingham, people who cared for a chronically ill or disabled family member lived almost a fifth longer than people who didn't.

Researchers looked at more than 3,000 caregivers, and found that for every year that 315 non-caregivers pass away, only 264 caregivers do — the other 51 lived significant longer than their counterparts. So there you go: good deeds pay. Sharing is caring. Caring is... Well, you know what we mean.

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Should We Pay For Organs?

If you're in need of an organ, the policy is strict: in the interest of fairness, you can't buy one — you'll have to wait in the organ-donation queue with everybody else in need. (Except for the black market, but you don't really want to go down that route.) Except, maybe it wouldn't be the worst thing. New research analysis by Canada's University of Calgary indicates that if every kidney donor was paid $10,000, the system would actually lose less money, and there would be more kidneys to go around.

Still, even if it were more cost-effective, other analysts argue that offering money for organs is a terrible road to go down. Plus, the analysis might have missed a beat: “If we paid $10,000, a lot of altruistic donors would say that it’s just a cash transaction," said the National Kidney Foundation's Dr. Stephen Pastan. "Donations could go down."

Well, it'd make a good start to a sci-fi movie, anyway...

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Growing Up Poor Changes Your Brain

OK, this is scary: new cross-university research indicates if your brain faces chronic stress as a child, say, because you're growing up poor, your brain function is impaired for life. A bunch of researchers, including University of Illinois, Cornell University, University of Michigan, and University of Denver, found that children whose family were low-income when the child was young had greater activity in the amygdala than those from medium and high-income families. The amygdala is the part of the brain associated with fear and other negative emotions.

Overuse of the amygdala, said the study's authors, was associated with "depression, anxiety, impulsive aggression and substance abuse" — basically, issues with regulating emotions. It's long been known that poverty in childhood puts kids at risk for a variety of physical and psychological issues, but the effects on brain chemistry hadn't been so clearly discovered until now.

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So Many New Animals Exist

On a happier note, an exhaustive four-year study of previously-unexplored patches of the Amazon rainforest have found nearly 500 new species. Courtesy of the World Wildlife Foundation, these include: a flame-patterned lizard, a thumbnail-sized frog, a vegetarian piranha, a brightly colored snake, and a gorgeous pink orchid.

The new monkey species, the Callicebus caquetensis, is particularly adorable: when babies are feeling particularly content, they start purring at one another. See: Some things are still well and good in the world.

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