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Wikimedia Commons

6 Prehistoric Body Parts You Don’t See Anymore

Wikimedia Commons
Wikimedia Commons

Sometimes the sheer wonder of the natural world can be overwhelming. So, at the risk of oversimplifying the following crazy-cool animals, allow us to highlight their most unusual structural features. You may find yourself wondering why these body parts haven’t been around in many, many millenia.

1. Anvil Fin - Stethacanthus

In most ways, Stethacanthus (above) probably looked like any of your average early sharks. Except, that is, for its bizarre anvil-shaped dorsal fin (sometimes described as an “ironing board”). Equally nonsensical is the rough patch of sharp, tooth-shaped scales atop the anvil/ironing board, and a second scaly patch on the top of its head which, like the anvil, seems pretty un-hydrodynamic.

At five to six feet long, Stethacanthus was among the smaller prehistoric sharks, and scientists have theorized that the weird dorsal shape might have served to mimic a huge mouth to deter would-be predators or competitors. But Stethacanthus wasn’t a very dynamic hunter, and probably stayed in shallower, coastal waters, feeding on small fish and crustaceans. More likely, the fin, the scales, and a pair of long, thin “whips” trailing from its sides have something to do with mating displays, as they’re only found on males of the genus.

2. Circular “Saw” Jaw - Helicoprion

Ray Troll

Helicoprion, a giant, shark-like “ratfish,” was host to one of the most notoriously baffling body parts ever discovered: a circular set of teeth that scientists now believe resembled a buzzsaw upended in the fish’s lower jaw. Back in 1899, scientist Alexander Karpinsky was left guessing after he discovered Helicoprion’s whirlygig of teeth sans the rest of the fish. For years, scientists and enthusiastic illustrators traded guesses as to how the teeth fit into an entire animal, which would prove to have reached lengths of 25 feet. They knew Helicoprion replaced its teeth intermittently, much like modern sharks, but it didn’t seem to share other sharky characteristics. The specifics of Helicoprion’s tooth replacement evaded them until earlier this year, when a team of Idaho State paleontologists pinned down the (still totally weird) mouth-mechanism seen here.

3. Tail Club - Ankylosaur

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Most dino-inclined kids are well aware of the concept of the “tail club”: a tail which ends in a massive knob of bone and ossified tissue, good for defending against attackers, competing for mates, and knocking around whatever needs knocking around. Paleobiologist Victoria Arbour recently utilized CT scans to digitally reconstruct the muscles of the Ankylosaur’s tail club, allowing her to estimate the force with which the tail could smash. Her conclusions: Tail clubs with large “knobs” could break bone. Smaller-knobbed tail clubs, though, could do some lesser damage, leaving open the question as to whether tail clubs were more for offense, defense, or show. You know Ankylosaurs and their knob comparing.

4. “Baleen” Teeth - Pterodaustro

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And speaking of size, Pterodaustro had the longest rostrum (snout) of any pterosaur, but its bottom teeth were truly the weirdest. Set in scooping underbite, its teeth were so long and skinny that they were all rooted a single, long groove in the bottom jaw instead of individual sockets. The overall effect is reminiscent of the baleen in modern whales, leading paleontologists to believe that Pterodaustro fed much in the same way, scooping up mouthfuls of muck from the shallows and filtering away the water to munch on what was left.

In modern whales, baleen is made out of keratin and is therefore more like hair than teeth, and for some time, scientists believed Pterodaustro’s teeth were composed of a similar protein. But closer inspection revealed microscopic evidence of real, toothy characteristics: enamel, dentine, and pulp cavities.

Here’s an hilarious and slightly outdated illustration of Pterodaustro in a synth rock video, for some reason.

5.  The Ol’ Single Claw - Mononykus

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Named for the Latin Mono-, meaning “one,” and nykus, meaning “nail or claw,” Mononykus olecranus is a dinosaur best known for having only one claw on each of its puny forelimbs. And you thought T. rex had it bad.

Scientists have entertained many competing theories over the years as to the behavior of Mononykus olecranus, whose forelimbs would have been fairly useless for hunting or even grazing. The supposed presence of a birdlike chest ridge had many scientists believing M. olecranus may have been a winged but flightless bird. But a 2005 study examining range of motion in those stubby forearms decisively concluded that M. olecranus would have used its claws to scratch into insect nests and scoop out food. In this way, Mononykus’ single claw is analogous to modern animals with similar diets like anteaters and pangolins, though their claw count isn’t quite so minimalist.

6. Shoulder Spikes - Gigantspinosaurus

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With one of the most satisfying names in taxonomy, this dino is named after the gigantic spikes that were situated on his shoulders. Exactly how they were situated on those shoulders (and therefore their exact purpose) is yet unknown, though it’s reasonable to guess that they were used for displaying and/or competing for mates. And before you ask, Gigantspinosaurus is indeed a stegosaur, just one of several members of the genus Stegosaurus. Another of Gigantspinosaurus’ close relatives, Kentrosaurus, may have had similar spikes on its shoulders, or possibly on its hips (on this spike-placement question, the jurassic jury’s still out). But Gigantspinosaurus appropriately maintains the record of largest shoulder spikes in prehistory.

A very special thanks to our good friend, prehistorian Brian Switek, for lending his expert eye to this piece!

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Authorities Want This Roadside Bear Statue in Wales Removed Before It Causes More Accidents
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There are no real bears in the British Isles for residents to worry about, but a statue of one in the small Welsh town of Llanwrtyd Wells has become a cause of concern. As The Telegraph reports, the statue is so convincing that it's scaring drivers, causing at least one motorist to crash her car. Now road safety officials are demanding it be removed.

The 10-foot wooden statue has been a fixture on the roadside for at least 15 years. It made headlines in May of 2018 when a woman driving her car saw the landmark and took it to be the real thing. She was so startled that she veered off the road and into a street sign.

After the incident, she complained about the bear to highways officials who agreed that it poses a safety threat and should be removed. But the small town isn't giving in to the Welsh government's demands so quickly.

Wooden bear statue.

The bear statue was originally erected on the site of a now-defunct wool mill. Even though the mill has since closed, locals still see the statue as an important landmark. Llanwrtyd Wells councilor Peter James called it an "iconic gateway of the town," according to The Telegraph.

Another town resident, who wished to remain anonymous, told The Telegraph that the woman who crashed her car had been a tourist from Canada where bears are common. Bear were hunted to extinction in Britain about 1000 years ago, so local drivers have no reason to look out for the real animals on the side of the road.

The statue remains in its old spot, but Welsh government officials plan to remove it themselves if the town doesn't cooperate. For now, temporary traffic lights have been set up around the site of the accident to prevent any similar incidents.

[h/t The Telegraph]

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10 Scientific Benefits of Being a Dog Owner
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iStock

The bickering between cat people and dog people is ongoing and vicious, but in the end, we're all better off for loving a pet. But if anyone tries to poo-poo your pooch, know that there are some scientific reasons that they're man's best friend.

1. YOU GET SICK LESS OFTEN.

Dog snuggling on a bed with its person.
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If cleaning commercials are to be believed, humanity is in the midst of a war against germs—and we shouldn't stop until every single one is dead. In reality, the amount of disinfecting we do is making us sicker; since our bodies are exposed to a less diverse mix of germs, our entire microbiome is messed up. Fortunately, dogs are covered in germs! Having a dog in the house means more diverse bacteria enters the home and gets inside the occupants (one study found "dog-related biodiversity" is especially high on pillowcases). In turn, people with dogs seem to get ill less frequently and less severely than people—especially children—with cats or no pets.

2. YOU'RE MORE RESISTANT TO ALLERGIES.

Child and mother playing with a dog on a bed.
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While dog dander can be a trigger for people with allergies, growing up in a house with a dog makes children less likely to develop allergies over the course of their lives. And the benefits can start during gestation; a 2017 study published in the journal Microbiome found that a bacterial exchange happened between women who lived with pets (largely dogs) during pregnancy and their children, regardless of type of birth or whether the child was breastfed, and even if the pet was not in the home after the birth of the child. Those children tested had two bacteria, Ruminococcus and Oscillospira, that reduce the risk of common allergies, asthma, and obesity, and they were less likely to develop eczema.

3. YOU'LL HAVE BETTER HEART HEALTH.

Woman doing yoga with her dog.
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Everything about owning a dog seems to lend itself to better heart health. Just the act of petting a dog lowers heart rate and blood pressure. A 2017 Chinese study found a link between dog ownership and reduced risk of coronary artery disease, while other studies show pet owners have slightly lower cholesterol and are more likely to survive a heart attack.

4. YOU GET MORE EXERCISE.

Person running in field with a dog.
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While other pets have positive effects on your health as well, dogs have the added benefit of needing to be walked and played with numerous times a day. This means that many dog owners are getting 30 minutes of exercise a day, lowering their risk of cardiovascular disease.

5. YOU'LL BE HAPPIER.

Woman cuddling her dog.
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Dog owners are less likely to suffer from depression than non-pet owners. Even for those people who are clinically depressed, having a pet to take care of can help them out of a depressive episode. Since taking care of a dog requires a routine and forces you to stay at least a little active, dog owners are more likely to interact with others and have an increased sense of well-being while tending to their pet. The interaction with and love received from a dog can also help people stay positive. Even the mere act of looking at your pet increases the amount of oxytocin, the "feel good" chemical, in the brain.

6. YOU HAVE A MORE ACTIVE SOCIAL LIFE.

Large bulldog licking a laughing man.
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Not only does dog ownership indirectly tell others that you're trustworthy, your trusty companion can help facilitate friendships and social networks. A 2015 study published in PLOS One found that dogs can be both the catalyst for sparking new relationships and also the means for keeping social networks thriving. One study even showed that those with dogs also had closer and more supportive relationships with the people in their lives.

7. YOUR DOG MIGHT BE A CANCER DETECTOR.

Man high-fiving his dog.
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Your dog could save your life one day: It seems that our canine friends have the ability to smell cancer in the human body. Stories abound of owners whose dogs kept sniffing or licking a mole or lump on their body so they got it checked out, discovering it was cancerous. The anecdotal evidence has been backed up by scientific studies, and some dogs are now trained to detect cancer.

8. YOU'LL BE LESS STRESSED AT WORK.

Woman working on a computer while petting a dog.
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The benefits of bringing a dog to work are so increasingly obvious that more companies are catching on. Studies show that people who interact with a pet while working have lower stress levels throughout the day, while people who do not bring a pet see their stress levels increase over time. Dogs in the office also lead to people taking more breaks, to play with or walk the dog, which makes them more energized when they return to work. This, in turn, has been shown to lead to much greater productivity and job satisfaction.

9. YOU CAN FIND OUT MORE ABOUT YOUR PERSONALITY.

Man running in surf with dog.
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The kind of dog you have says a lot about your personality. A study in England found a very clear correlation between people's personalities and what type of dogs they owned; for example, people who owned toy dogs tended to be more intelligent, while owners of utility dogs like Dalmatians and bulldogs were the most conscientious. Other studies have found that dog owners in general are more outgoing and friendly than cat owners.

10. YOUR KIDS WILL BE MORE EMPATHETIC.

A young boy having fun with his dog.
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Though one 2003 study found that there was no link between pet ownership and empathy in a group of children, a 2017 study of 1000 7- to 12-year-olds found that pet attachment of any kind encouraged compassion and positive attitudes toward animals, which promoted better well-being for both the child and the pet. Children with dogs scored the highest for pet attachment, and the study notes that "dogs may help children to regulate their emotions because they can trigger and respond to a child's attachment related behavior." And, of course, only one pet will happily play fetch with a toddler.

A version of this story originally ran in 2015.

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