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Hannah Keyser

Did Ostriches and Emus Ever Fly?

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Hannah Keyser

Not recently, of course. But what about their ancestors? The question is: Did the flightless birds of today, a family known as Ratites, evolve from flightless birds of yore or did their airborne ancestors lose the ability to fly over the millennia?

Research has shown that ostriches' wings are not just ornamental, but rather help the animals—and some other, if not all large, flightless birds—maintain their balance and maneuver when running at high speeds. This would support the possibility that these seemingly useless wings are not necessarily vestigial and, therefore, that the birds never had the ability to fly.

This fits the long-held hypothesis that Ratites evolved around 200 million years ago when Australia, New Zealand, South America, Africa, Antarctica, Madagascar, and India were merged into a supercontinent known as Gondwana. As shifting tectonic plates broke Gondwana apart, the ancestral giant flightless birds were separated from each other and eventually evolved into the ostriches, emus, and New Zealand’s recently extinct giant moa.

However, one question remained: How do you reconcile an ancient flightless bird with the existence of dinosaurs, who would have made quick work of earth-bound prey? The answer is, you don't. Fossil evidence supported the explanation that Ratites evolved around 65 million years ago, just as the dinosaurs were dying out. But by then, the continents had already broken apart, upending the existing theory that all the contemporary Ratites evolved from the same flightless ancestor.

The author with an ostrich. Can confirm, he did not fly.

More recent research led by Dr. Matthew Phillips, an ARC Postdoctoral Fellow at the ANU Research School of Biology, addressed this issue and found that, in fact, Ratites dispersed across the continents at a time when their wings were used for flight and, from there, independently evolved to be larger and flightless once the extinction of the dinosaurs removed the pressure to escape to higher ground.

“Our study suggests that the flighted ancestors of Ratites appear to have been ground-feeding birds that ran well," Phillips wrote. "So the extinction of the dinosaurs likely lifted predation pressures that had previously selected for flight and its necessary constraint, small size. Lifting of this pressure and more abundant foraging opportunities would then have selected for larger size and consequent loss of flight.”

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Animals
Owning a Dog May Add Years to Your Life, Study Shows
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We've said that having a furry friend can reduce depression, promote better sleep, and encourage more exercise. Now, research has indicated that caring for a canine might actually extend your lifespan.

Previous studies have shown that dog owners have an innate sense of comfort and increased well-being. A new paper published in Scientific Reports and conducted by Uppsala University in Sweden looked at the health records of 3.4 million of the country's residents. These records typically include personal data like marital status and whether the individual owns a pet. Researchers got additional insight from a national dog registry providing ownership information. According to the study, those with a dog for a housemate were less likely to die from cardiovascular disease or any other cause during the study's 12-year duration.

The study included adults 40 to 80 years old, with a mean age of 57. Researchers found that dogs were a positive predictor in health, particularly among singles. Those who had one were 33 percent less likely to die early than those who did not. Authors didn't conclude the exact reason behind the correlation: It could be active people are more likely to own dogs, that dogs promoted more activity, or that psychological factors like lowered incidences of depression might bolster overall well-being. Either way, having a pooch in your life could mean living a longer one.

[h/t Bloomberg]

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Big Questions
Why Don't We Eat Turkey Tails?
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Turkey sandwiches. Turkey soup. Roasted turkey. This year, Americans will consume roughly 245 million birds, with 46 million being prepared and presented on Thanksgiving. What we don’t eat will be repurposed into leftovers.

But there’s one part of the turkey that virtually no family will have on their table: the tail.

Despite our country’s obsession with fattening, dissecting, and searing turkeys, we almost inevitably pass up the fat-infused rear portion. According to Michael Carolan, professor of sociology and associate dean for research at the College for Liberal Arts at Colorado State University, that may have something to do with how Americans have traditionally perceived turkeys. Consumption was rare prior to World War II. When the birds were readily available, there was no demand for the tail because it had never been offered in the first place.

"Tails did and do not fit into what has become our culinary fascination with white meat," Carolan tells Mental Floss. "But also from a marketing [and] processor standpoint, if the consumer was just going to throw the tail away, or will not miss it if it was omitted, [suppliers] saw an opportunity to make additional money."

Indeed, the fact that Americans didn't have a taste for tail didn't prevent the poultry industry from moving on. Tails were being routed to Pacific Island consumers in the 1950s. Rich in protein and fat—a turkey tail is really a gland that produces oil used for grooming—suppliers were able to make use of the unwanted portion. And once consumers were exposed to it, they couldn't get enough.

“By 2007,” according to Carolan, “the average Samoan was consuming more than 44 pounds of turkey tails every year.” Perhaps not coincidentally, Samoans also have alarmingly high obesity rates of 75 percent. In an effort to stave off contributing factors, importing tails to the Islands was banned from 2007 until 2013, when it was argued that doing so violated World Trade Organization rules.

With tradition going hand-in-hand with commerce, poultry suppliers don’t really have a reason to try and change domestic consumer appetites for the tails. In preparing his research into the missing treat, Carolan says he had to search high and low before finally finding a source of tails at a Whole Foods that was about to discard them. "[You] can't expect the food to be accepted if people can't even find the piece!"

Unless the meat industry mounts a major campaign to shift American tastes, Thanksgiving will once again be filled with turkeys missing one of their juicier body parts.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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