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17 Noisy Facts About 17-Year Cicadas

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This summer, prepare for the return of Brood V.

No, that’s not the title of a B horror flick, but it does involve an army of insects rising from the earth Night of the Living Dead–style. Seventeen-year cicadas spend over 99 percent of their lives underground, only to crawl out by the billions on a warm spring night in their 17th year. Then, after dedicating a few weeks to repopulating the brood, their bodies fall back to the ground they emerged from.

Different cicada broods resurface on different years. Brood V was last seen in Ohio, West Virginia, and surrounding states in 1999, and now the offspring of that last batch are finally ready to emerge. Whether they’ll be in your neighborhood or not, these are 17 facts about the periodical bugs worth knowing.

1. THEY’RE ACTIVE THEIR WHOLE LIVES.

Just because we can’t see (or hear) cicadas when they’re a few feet under doesn’t mean they aren’t keeping busy. “They’re not hibernating ... they’re just slow-growing,” Louis Sorkin, an entomologist with the American Museum of Natural History, tells mental_floss. According to Sorkin, 17-year cicadas live underground as immature nymphs before reaching full adulthood above the surface. And because they’re still too young to procreate, one major activity occupies their time: eating.

2. THEIR DIET MAY EXPLAIN THEIR LONG LIFECYCLE.

A cicada nymph’s meal of choice is xylem, a type of sap they slurp from tree roots. The fluid is more than 90 percent water and very poor in nutrients. Some cicada experts believe that the insect’s lousy diet may be one of the reasons behind its drawn-out maturation process.

3. THEY USE TREES TO KEEP TRACK OF TIME.

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The cicada’s super-accurate timekeeping skills have been puzzling scientists for centuries. According to one paper published in 2000, they may be using more than just their biological clocks to count down the years. For the study, researchers transplanted 15-year-old 17-year cicada nymphs beneath a tree that had been manipulated to blossom twice in one season. After feeding on its roots, the insects emerged one year early. This suggests that cicadas use the influx of sugars and proteins from a blossoming tree’s roots to mark the passage of time underground.

4. MATH HELPS THEM AVOID PREDATORS.

Seventeen-year cicadas aren’t the only members of the periodical cicada genus. They share the title with 13-year cicadas, who, as their name suggests, live a similar lifecycle except it ends four years earlier. Thirteen and 17 may seem like arbitrary amounts of time to stay buried in the dirt, but the numbers share a mathematical property that may help keep the insects alive. Both 13 and 17 are decently large prime numbers, which means they aren’t divisible by any number smaller than themselves. This makes it next to impossible for predators to adapt to the cicadas’s emergences. Stephen Jay Gould wrote in his 1977 book Ever Since Darwin: Reflections in Natural History, “Consider a predator with a cycle of five years; if cicadas emerged every 15 years, each bloom would be hit by the predator. By cycling at a large prime number, cicadas minimize the number of coincidences.” That’s an impressive math trick for an arthropod.

5. THEY EVOLVED DURING THE LAST ICE AGE.

The prime number trick is just one of the reasons some cicadas live to be 17. Louis Sorkin tells us their long lifespan is likely a leftover adaptation from the last ice age. Periodical cicadas are believed to have evolved during the Pleistocene Epoch at a time when North America’s climate was fairly unpredictable. By staying underground for as long as possible, cicadas had a greater chance of avoiding a cold and deadly summer when it was finally time to come up.

6. THEY’RE TRIGGERED BY TEMPERATURE.

Chace Nelson, Flickr // CC BY-NC-ND 2.0

When it’s their year to emerge, 17-year cicadas wait until the soil 8 inches beneath the surface warms up to around 64 degrees. This specific temperature point is their signal to tunnel out of the earth and up the nearest vertical surface they can find, whether it’s a tree, fence post, or screen door. According to Sorkin, they’ll even climb up the leg of a person standing nearby.

7. THERE ARE 12 DIFFERENT BROODS.

Not every 17-year cicada emerges at the same time (if they did, the eastern half of the country couldn’t be blamed for taking a prolonged vacation every 17 summers). The insects are grouped into 12 distinct broods spanning from New York to Oklahoma (along with three broods of 13-year). When a brood procreates, their offspring are the ones who carry on that same brood 17 years later. Entomologist C.L. Marlatt was the first person to assign Roman numerals to the periodical cicadas in the late 19th century. Since then, a handful of the original broods have gone extinct.

8. THEY ARRIVE IN LARGE NUMBERS.

A single brood can contain billions of cicadas. When Brood V emerges this spring, their populations will be as dense as 1.5 million insects per square acre in some parts of the region. Simultaneously emerging in such great numbers is a survival strategy known as predator satiation. “[Predators] get completely full and engorge themselves,” Sorkin says. “They can’t catch everything, so you’ll have lots of [cicadas] doing fine and progressing to the next stage of their lives.” This ends up working out for cicadas as well as for the birds, rodents, and reptiles that get a surprise feast whenever they show up.

9. THEY’RE A TREAT FOR HUMANS, TOO.

Humans have a long history of dining on cicadas. Before European colonists arrived, indigenous North Americans enjoyed roasting them like peanuts. Today the bugs have become something of an unlikely food trend. Not only do they fit into the movement to utilize insects as a protein source, but they’re also gluten-free, low in carbs, and hyper-seasonal. When one Missouri ice cream shop introduced a batch of cicada-flavored ice cream in 2011, it sold out before hitting the display case. During the most recent summer of Brood II one chef served cicadas at his James Beard-nominated sushi restaurant in Connecticut. If you can’t find cicadas on the menu of your favorite local spot, catching them and cooking them at home is easy enough to do. Sorkin recommends grinding them up to make a flour, or even sautéing the critters with garlic and oil and eating them whole.

But if you want to put cicada on the menu, there are a couple of things to consider. Experts recommend that those with a shellfish allergy avoid the bugs, as should anyone who’s concerned about mercury in their diet: In 2004, researchers found cicadas could contain as much mercury as certain fish.

10. THEY LEAVE A LOT OF EXOSKELETONS BEHIND.

Before they can become adults, cicadas must get to a high-up spot to shed their immature skin. From the old exoskeleton a soft, new body unfurls, leaving behind the perfect shell of its nymphal self. Even though they’re harmless, the cicada skins can prove to be a nuisance for some. News stories from Brood II’s 1996 emergence reported shells piling up so high in some spots that people were using snow shovels to clear their driveways.

11. THEY’RE NOT LOCUSTS. 

While it’s true that 17-year cicadas do emerge in plague-like proportions, that doesn’t make them locusts. Sorkin says this misnomer was likely spread by European colonists who knew the bugs from the Bible. In reality, locusts are a type of grasshopper, and they tend to be much more destructive than relatively harmless cicadas.

12. THEIR SONGS CAN REACH 100 DECIBELS.

A cicada above ground has one job to do: make baby cicadas. To accomplish this task, an adult male will spend his last four to six weeks of life in furious song. There are three different species of 17-year cicadas and each one has a distinct mating call. The sounds are sometimes reminiscent of chirps, rattles, or high-pitched screams, and when males gather in trees to form a chorus, the noise can exceed 100 decibels. That’s about as loud as a car stereo playing at max volume. The song can be heard by females up to a mile away, and if she likes what she hears, she responds by flicking her wings.

13. THEY’RE ATTRACTED TO POWER TOOLS.

The deafening roar of a chorus of cicadas is often compared to the sound of heavy duty power equipment. The noises are so similar that confused females have been known to swarm around people using lawn mowers, leaf blowers, and other loud tools.

14. THEY LAY THEIR EGGS IN TREE BRANCHES.

After the female cicada has mated, it’s time to lay her eggs. She uses a structure on her rear called an ovipositer to slice Y-shaped gashes on the tips of tree branches. Females can lay up to several dozen eggs in a single branch and as many as 400 eggs spread out over 40 to 50 sites. After incubating for several weeks, the newly-hatched cicada nymphs fall to the earth, where they will spend their next 17 years of life.

15. THEY’RE ONE OF THE OLDEST INSECTS.

With a lifespan of 17 years, cicadas are among the longest-living insects on earth. But queen termites have them beat: A colony's queen can live as long as 50 years.

16. THEY HAVE FIVE EYES.

Chrissy Wainwright, Flickr // CC BY-NC 2.0

An adult cicada is easily identified by the opaque pair of compound, usually crimson, eyes bubbling out from the sides of its head. But this isn’t the only set of eyes the creature owns. It also possesses a cluster of three smaller eyes hiding in plain sight on the top of its forehead. These eyes are called ocelli and are much simpler than its more prominent pair.

17. EVERY 221 YEARS, 13-YEAR AND 17-YEAR CICADAS CO-EMERGE.

The cycles of 17-year and 13-year cicada broods in the same region rarely coincide, which may be an evolutionary tactic to keep them from interbreeding. But you can mark your calendars now: the next co-emergence event is set to take place in Missouri in 2219.

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Atlanta Shelters Give Pups a Temporary Home for the Holidays
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The holidays are looking a little brighter for adoptable dogs from two animal shelters in Atlanta, Georgia. As ABC News reports, a new program called Home for the Pawlidays is providing temporary homes to longer-term residents of Fulton County Animal Services and DeKalb County Animal Services for the week of Thanksgiving.

The initiative was organized by Atlanta's LifeLine Animal Project, a local group dedicated to providing healthcare and homes to shelter dogs. The dogs that were chosen for the project may be older, have special health needs, or other issues that make it more difficult to find them forever homes.

But from November 18 to 25, the dogs are getting to spend time away from the shelter and in the homes of loving foster families.

“We were thinking, everyone gets a break from work, and they should get a break from the shelter,” LifeLine’s public relations director Karen Hirsch told ABC News.

Some caretakers have already fallen in love with their four-legged house guests. Foster Heather Koth told ABC that she hadn’t been considering adoption, but after meeting Missy the shelter dog, she now plans to foster her until she has a permanent home or possibly adopt the dog herself.

And for the dogs that can’t be kept by their temporary owners, just a week of quality playtime and sleeping in a real bed can make a huge impact. You can check out photos of the pets who are benefiting from the program this week below.

[h/t ABC News]

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25 Things You Didn't Know About Turkeys
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Most of us probably associate turkey with a sumptuous Thanksgiving spread, but there’s a lot more to the big bird than how delicious it is alongside your grandma’s famous cranberry sauce. Here are a few bits of knowledge you can drop over the dinner table—when you’re not fighting with your family over white meat or dark meat, that is.

1. THE NORTH AMERICAN WILD TURKEY POPULATION WAS ALMOST WIPED OUT.

Wild turkey
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Wild turkeys once roamed the continent en masse, but by the early 20th century, the entire U.S. population had been whittled down to a mere 30,000 due to hunting and the destruction of their woodland habitats. In the 1940s, many of the remaining birds were relocated to parts of the U.S. with recovering woodlands so the turkeys could repopulate. Despite these efforts, by 1973, there were still just 1.5 million wild turkeys in North America. Today, that number is up to about 6 million.

2. TURKEY APPENDAGES ARE LIKE MOOD RINGS.

Wild turkey
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The dangly appendage that hangs from the turkey’s forehead to the beak is called a snood. The piece that hangs from the chin is the wattle. These fleshy flaps can change color according to the turkey’s physical and mental health—when a male turkey (called a tom, of course) is trying to attract a mate, the snood and wattle turn bright red. If the turkey is scared, the appendages take on a blue tint. And if the turkey is ailing, they become very pale.

3. TURKEYS CAN FLY.

Wild turkey in flight
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Well, domestic turkeys that are bred to be your Thanksgiving centerpiece can’t. They’re too heavy. But wild turkeys can, reportedly at speeds up to 55 miles per hour. Though they don’t go very far—usually less than 100 yards—wild turkeys are among the five largest flying birds in the world. They’re in good company: Others on the list include the swan and the albatross.

4. THEY CAN ALSO SWIM.

Wild turkey drinking water
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Turkeys don’t swim often, it seems, but they can, by tucking their wings in, spreading their tails, and kicking. In 1831, John James Audubon wrote, “I have been told by a friend that a person residing in Philadelphia had a hearty laugh on hearing that I had described the Wild Turkey as swimming for some distance, when it had accidentally fallen into the water. But be assured, kind reader, almost every species of land-bird is capable of swimming on such occasions, and you may easily satisfy yourself as to the accuracy of my statement by throwing a Turkey, a Common Fowl, or any other bird into the water.”

5. TURKEY POOP CAN TELL YOU A LOT.

A handler picking up turkey poop at the White House Turkey Pardon in 2013.

The next time you happen across turkey poop—which happens all the time, we know—take a closer look at it. If the droppings are shaped like a “J,” they were left there by a male turkey. Spiral-shaped poo? The culprit is female.

The citizens of Pilot Rock, Oregon, probably don’t much care about the shape of the stuff, but more about the quantity of it. Earlier this year, Pilot Rock turned to the Oregon Department of Fish and Wildlife (ODFW) for help combating a flock of 50 to 70 wild turkeys that would periodically invade the town, destroy gardens, perch in trees, and poop on pickup trucks. The ODFW offered several solutions, but as far as we know the turkeys still rule the roost at Pilot Rock.

6. TURKEY PROBABLY WASN'T ON THE PILGRIMS' MENU.

A recreation of the Pilgrims' first settlement
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Thanks to historical records, we know for sure that the Wampanoag brought deer, and the English brought fowl—likely ducks and geese.

7. BEN FRANKLIN DIDN'T REALLY WANT THE TURKEY TO BE OUR NATIONAL BIRD.

A drawing of Ben Franklin.
Getty / Hulton Archive / Handout

You may have heard that at least one of our Founding Fathers lobbied hard to make the turkey our national symbol instead of the noble bald eagle. That’s not quite true, but in a letter to his daughter, he did expound on the character of each, which may be where the rumor got started:

“For my own part I wish the Bald Eagle had not been chosen the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his Nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him.

“With all this injustice, he is never in good case but like those among men who live by sharping & robbing he is generally poor and often very lousy. Besides he is a rank coward: The little King Bird not bigger than a Sparrow attacks him boldly and drives him out of the district. He is therefore by no means a proper emblem for the brave and honest Cincinnati of America who have driven all the King birds from our country…

“I am on this account not displeased that the Figure is not known as a Bald Eagle, but looks more like a Turkey. For the Truth the Turkey is in Comparison a much more respectable Bird, and withal a true original Native of America… He is besides, though a little vain & silly, a Bird of Courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his Farm Yard with a red Coat on.”

8. ANOTHER TURKEY FAN: ALEXANDER HAMILTON.

Portrait of Alexander Hamilton
Wikimedia Commons // Public Domain

Yep, A. Ham liked turkey. In fact, he thought eating turkey was practically a god-given right, and once remarked that "No citizen of the U.S. shall refrain from turkey on Thanksgiving Day."

9. TEDDY ROOSEVELT BELIEVED THE BIRDS WERE CUNNING PREY.

Teddy Roosevelt on a hunting trip in Africa.
Getty / Hulton Archive / Stringer

Ol’ TR may have been accustomed to hunting big game, but wild turkeys held a special place in his heart. He believed they were every bit as challenging to hunt as deer. In his 1893 book Hunting Trips of a Ranchman and the Wilderness Hunter, he wrote, “The wild turkey really deserves a place beside the deer; to kill a wary old gobbler with the small-bore rifle, by fair still-hunting, is a triumph for the best sportsman.”

10. WILD TURKEYS HAVE BETTER VISION THAN YOU DO.

Close up of wild turkey's head
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Their fantastic vision is probably one reason Teddy Roosevelt found turkeys such a challenge to hunt. They can detect motion from many yards away, have vision three times greater than 20/20, and have peripheral vision of about 270 degrees. Ours, comparatively, is only 180. And although turkeys can’t see in 3D, they can see UVA light, which helps them better identify predators, prey, mates, and food.

11. THE TOP TURKEY-PRODUCING STATE MAY SURPRISE YOU.

Domesticated turkeys on a farm
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You may know Minnesota for producing Prince, the Mall of America, and Target. But we also have the Land of 10,000 Lakes to thank for our Thanksgiving turkeys. According to the Minnesota Turkey Growers Association, approximately 46-48 million turkeys are produced in Minnesota every year. In fact, it’s where the turkey that receives a presidential pardon hails from every year. Speaking of which ...

12. THE PRESIDENTIAL TURKEY PARDON MAY DATE BACK TO ABE LINCOLN.

President Barack Obama pardons a turkey in 2011.
Getty / Mark Wilson / Staff

Officially, the tradition of the sitting president of the United States pardoning his Thanksgiving turkey dates back to John F. Kennedy, who decided to let his gift from the National Turkey Federation off the hook. But he wasn't the first president to let a turkey go free: When Abraham Lincoln’s son Tad befriended one of the birds intended for Christmas dinner in 1863, kind-hearted Abe granted it a stay of execution.

13. THE FIRST TV DINNER MEAL: THANKSGIVING LEFTOVERS

Thanksgiving TV dinner
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In 1953, Swanson ended up with 10 train cars full of frozen turkeys—260 tons of them—when an overzealous buyer ordered too many turkeys for the holidays. Salesman Gerry Thomas solved the problem by ordering 5,000 aluminum trays and setting up an assembly line of workers to scoop dressing, peas, and sweet potatoes into the compartments. Slices of turkey rounded out the meal, which Swanson sold for 98 cents. The idea was a hit: The following year, 10 million turkey TV dinners were sold.

14. NATIONAL TURKEY LOVERS’ MONTH ISN’T WHEN YOU THINK.

Grilled meats on a silver tray
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Everyone eats turkey in November and December, so there’s not a lot of need for extra poultry promotion during those months. If you want to celebrate National Turkey Lovers’ Month, you’ll have to do it in June with some turkey brats and burgers on the grill.

15. THE TURKEY YOU’LL BE EATING IS PROBABLY ABOUT 18 WEEKS OLD.

Roasted turkey on a platter
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That’s how long it typically takes the birds to grow to maturity, which is when they’re usually slaughtered.

16. THERE WAS ALMOST A TURKEY SIDEKICK IN POCAHONTAS.

Loren Javier via Flickr // CC BY-ND 2.0

At one point, Disney thought Pocahontas needed a little comic relief, so they hired John Candy to voice a wisecracking woodland fowl named Red Feather. Sadly, Candy passed away while the logistics were being worked out, so animators dropped the turkey entirely and opted for a clever raccoon named Meeko.

17. NOT ALL TURKEYS GOBBLE.

Close up shot of a wild turkey
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If you hear a turkey making the distinctive noise we all associate with them, then you’re hearing a male communicating with his lady friends up to a mile away. Females make a clicking sound instead of a gobble.

18. IF YOU DON’T EAT TURKEY AT THANKSGIVING, YOU’RE IN THE MINORITY.

A black and white photo of a family gathering around the table as the mother brings in a turkey.
Getty / Evans / Stringer

According to the National Turkey Federation, 88 percent of Americans eat turkey at Thanksgiving.

19. TURKEY CRAVINGS CAUSED A SPIKE IN KFC SALES IN JAPAN.

A large Kentucky Fried Chicken sign
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When KFC opened its first stores in Japan in the 1970s, the company was surprised to find that sales soared during the holidays. The phenomenon stymied executives since most of Japan celebrates neither Thanksgiving nor Christmas. It was later discovered that foreigners craving holiday turkey had decided that KFC’s chicken was the next best thing. After the company figured this out, they played up the association with their “Kurisumasu ni wa kentakkii!” campaign—“Kentucky for Christmas.” It worked on tourists and locals alike, and today, Christmas Eve is still the highest-selling day for KFC Japan.

20. THERE IS PROPER TURKEY TERMINOLOGY.

A flock of turkeys on a farm with one staring directly into the camera.
Getty / Cate Gillon / Staff

You probably know that a group of turkeys is a flock, but they can also properly be called a “rafter.” And should you want to call baby turkeys something a little more precise, you can call them “poults.”

21. THE MAYA USED TURKEYS AS SACRIFICIAL OFFERINGS.

A Maya tripod plate featuring a bird
Los Angeles County Museum of Art via Wikimedia Commons // Public Domain

Archaeologists have found vases dating from 250-800 CE that have turkeys depicted on them. According to University of Wisconsin-Milwaukee art historian Andrea Stone, "turkeys were quintessential animals for feasting and for sacrificial offerings." The Maya even crafted tamales shaped like the birds.

22. DURING THE ‘70S, YOU COULD CALL JULIA CHILD FOR TURKEY ADVICE ON THANKSGIVING.

Julia Child in her kitchen in 1978
Lynn Gilbert via Wikimedia Commons // CC BY-SA 4.0

Even when she was at peak popularity, the famous chef refused to remove her phone number from public listings. According to friends, complete strangers would call Child on Thanksgiving to ask for advice on cooking the perfect turkey. Julia always answered the phone, and typically told callers whatever they needed to hear to get them to relax and enjoy the holiday. She even told some amateur cooks that turkey was best served cold anyway.

23. BIG BIRD IS A TURKEY.

Big Bird and Elmo at the Macy's Thanksgiving Day Parade.
Getty / Matthew Peyton / Stringer

Well, according to Sesame Street, he’s actually a canary—but his plumage makes him a turkey. The good people at American Plume & Fancy Feather provide Sesame Street with several thousand turkey feathers per costume to make sure Big Bird looks soft and fluffy.

24. THE BIRD IS NAMED AFTER THE COUNTRY.

Hagia Sophia in Istanbul, Turkey
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But the whole thing was a mistake. Centuries ago, the English began to import a rather tasty bird, now known as a helmeted guinea fowl, from Madagascar. But they didn’t know it was from Africa. Because it was imported to Europe from merchants in Turkey, the English believed the birds were also Turkish.

Later, when the Spanish arrived in the New World, they discovered Meleagris gallopavo—the wild turkey. It was delicious, so they started importing it back to Europe. Europeans thought it tasted like the “turkey” guinea fowl they had been enjoying, so they called it the same thing.

25. WHAT, EXACTLY, IS DARK MEAT?

Roasted turkey legs on a piece of butcher paper
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It’s just a different type of muscle than white meat. White meat is the result of glycogen, which doesn't need much oxygen from the blood because the muscles it fuels only require short bursts of energy. Dark meat, however, is found on wings, thighs, and drumsticks—muscles that are used for long periods of time and require more sustainable energy. It’s made dark by the proteins that convert fat into energy.

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