10 Surprising Facts About Animal Sex

iStock/Dias Studio
iStock/Dias Studio

Homo sapiens do not have a monopoly on strange sex. Peculiar mating rituals are prevalent throughout the animal kingdom. While writing my book Sex Weird-o-Pedia, these were the 10 most interesting animal sex facts I came across.

1. Turtle mating sounds make for good special effects.

It turns out that animal mating sounds can be really useful for capturing people’s attention. When the filmmakers of Jurassic Park wanted to create velociraptor sounds, they used recordings of tortoises getting it on.

2. Sharks have versatile birthing methods.

iStock/Placebo365

Australian scientists claim to have found a shark that gives virgin births. They studied a female zebra shark named Leonie, who laid eggs despite not being around a male shark in three years. Several years before her virgin birth, Leonie gave birth after mating with a male shark. She is believed to be the first known shark to reproduce both sexually and asexually.

3. Worms have really long dry spells.

You think it's been a long time since you've been intimate with someone? You've got nothing on worms. After sequencing the DNA of asexual translucent worms, NYU researchers discovered that one species, Diploscapter pachys, had not had sex for about 18 million years. This makes Diploscapter pachys one of the oldest known asexual species.

4. Fine fragrances turn big cats on.

Calvin Klein colognes have sex appeal to animals, too. Captive tigers and jaguars have become stimulated by the brand’s Obsession for Men scent. Forest rangers have used the scent to lure tigers out of the wild.

5. Barnacles have adaptable penises.

iStock/Photoshopped

Barnacles may have the most interesting penises in the animal kingdom. Their penises can stretch up to eight times the length of their body. And while many species' manhoods can change size, few can alter their shape. But researchers in Alberta found that barnacles that live in gentle waters have long and thin penises that are good for reach, while those in rough waters have short and wider penises that are better for holding off strong waves. The researchers then transported rough water barnacles to calmer waters and vice versa and found that after getting moved around, the barnacles adjusted their penis's shape to better fit their environment.

6. Water bugs mate loudly.

The water bug species Micronecta scholtzi are the loudest animal in the world relative to their size. The tiny critter reaches nearly 100 decibels when it rubs its penis against its abdomen. Basically, there is a rock concert going on whenever this bug releases a mating call.

7. Ducks defend themselves with their vaginas.

Duck penises can be terrifying: They are long and corkscrew-shaped and they can be used like a lasso to pull in females who are trying to escape unwanted advances. To fend off unwelcome mating attempts from overeager males, female ducks have evolved vaginas that twist in the opposite direction of their male counterparts’s corkscrew penises. Discover magazine referred to duck vaginas as “organic chastity belts."

8. Most birds don’t have penises.

iStock/sasapanchenko

Just 3 percent of bird species have penises. Ostriches and ducks have them, but eagles and penguins do not. When birds get erections, their penises fill up with lymph fluid instead of blood. Birds without penises transfer sperm from male to female via what is known as a cloacal kiss.

9. Male birds are desperate to impress potential mates.

As long as humans have been on Earth, guys have done incredibly stupid things to try to impress women. Male birds are not immune to this dynamic.

Little birds like chickadees will group together to take on larger predators. It has generally been assumed that they do this for protection purposes, but researchers in Brazil came to a different conclusion: The researchers created a few fake owls, one from a species that regularly eats smaller birds and another from a less threatening owl species. They found that across 79 different species of small birds, the less threatening owl was attacked more often by the smaller birds. Their conclusion was that the small birds used the weaker opponent as an opportunity to showcase their defense skills to potential mates.

10. Unlike humans, animals have gotten frisky in space.

According to NASA, no humans have ever had sex in space. But other animal species have been more active with their sexuality and reproductivity outside our atmosphere.

The first pregnant mammals to fly in outer space aboard a U.S. spacecraft were rats, and frogs have conceived in orbit.

In an effort to better understand how reproduction works in the absence of gravity, Russia’s space agency launched five geckos into orbit in 2014 so that they could observe how the lizards had sex in space. Sadly, the geckos froze to death before they touched back down to Earth.

In 2018, NASA scientists began a mission that involved sending human and bull sperm to outer space. Their intention was to study how microgravity affects the motility of sperm cells. Because if humans are to ever colonize space, we must boldly bone where no one has boned before.

Ross Benes is the author of the new book Sex Weird-o-Pedia: The Ultimate Book of Shocking, Scandalous, and Incredibly Bizarre Sex Facts.

Turn Your Couch or Bed Into an Office With This Comfortable Lap Desk

LapGear
LapGear

If you're not working in an office right now, you'll understand the freedom of taking a Zoom meeting from your back porch, jotting down notes from your bed, and filling out spreadsheets from your sofa. But working from home isn't always as comfortable as everyone thinks it is, especially if you're trying to get through the day while balancing a notebook, computer, and stationery on your lap. To give you the space you need while maintaining your well-earned place on the couch, LapGear has the perfect solution to your problems with their lap desk, which you can find on Amazon for $35.

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With more than 6000 reviews and a 4.8-star rating on Amazon, the lap desk can fit laptops and tablets up to 15.6 inches across and includes an integrated 5-inch-by-9-inch mouse pad and cell phone slot for better organization. There's even a ledge built into the desk to help keep your device from sliding when you're at an angle.

For some added comfort, the bottom of the desk is designed with dual-bolster cushions, so you'll never have to feel a hot laptop on your thighs again. The top surface is available in various colors like white marble ($30), silver carbon ($35), and oak woodgrain ($35) to work with your design aesthetic.

Find out more about LapGear’s lap desk here on Amazon.

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12 Fascinating Facts About Crows

Mick Thompson, Flickr // CC BY-NC 2.0
Mick Thompson, Flickr // CC BY-NC 2.0

Crows often get a bad rap. In many Western cultures, they've historically been associated with death, disease, and bad omens; reviled as crop-stealers by farmers, and condemned as nuisances by city dwellers. But the birds are fascinating creatures, adaptable and brainy to an extent that's almost scary. Here are a few facts about these crafty corvids that might surprise you.

1. All crows and ravens belong to the same genus.

Members of the genus Corvus can be found on every continent except Antarctica and South America (although other close relatives live there). To date, scientists have named 40 species. Colloquially, some of them are referred to as ravens while others are called crows, rooks, or jackdaws.

Historically, the name raven has been given to several of the big-bodied Corvus birds with shaggy feathers on their necks. Mid-sized members of the genus are usually called crows, while the very smallest species go by the name jackdaws. There's also a large-beaked outlier known as the rook, which was named after the unusual sound it makes. But pervasive as these labels may be, they're not scientific and do not reflect the latest research. Despite its informal name, the so-called Australian raven is more closely akin to the Torresian crow than it is to the common raven.

In the U.S., when people talk about crows and ravens, they're usually referring to the American crow (Corvus brachyrhynchos) and the common raven (Corvus corax). Telling them apart can be tough, but it is possible for eagle-eyed birders. One big indicator is size: The common raven is much larger, about the size of a red-tailed hawk. It also has a more wedge-shaped tail. As Kevin J. McGowan of the Cornell Lab of Ornithology writes on his crow FAQ page, ravens soar longer than crows, and you can see through their wing feathers as they fly (among other differences). And the birds' calls are substantially different. "American crows make the familiar caw-caw, but also have a large repertoire of rattles, clicks, and even clear bell-like notes," McGowan writes, whereas common ravens have "a deep, reverberating croaking or gronk-gronk. Only occasionally will a raven make a call similar to a crow's caw, but even then it is so deep as to be fairly easily distinguished from a real crow."

You can hear crow vocalizations here and raven vocalizations here.

2. Older crow siblings can help their parents raise newborn chicks.

Like a lot of intelligent animals, most crows are quite social. For instance, American crows spend most of the year living in pairs (they usually mate for life) or small family groups. During the winter months, they'll congregate with hundreds or even thousands of their peers to sleep together at night in a sprawling communal unit called a roost.

Come nesting season, a mated pair of crows might be lucky enough to receive chick-rearing help. Juvenile birds are frequently seen defending their parents' nest from predators. Other services they can provide include bringing food to mom and dad, or feeding their younger siblings directly. One study found that 80 percent of American crow nests surveyed had a helping hand. And some birds become regular nest assistants, providing aid to their parents for over half a decade.

3. When a crow dies, its neighbors may have a funeral.

The sight of a dead crow tends to attract a mob of a hundred or more live ones. During this ritual, the live crows almost never touch the dead one, which rules scavenging out as a motive. Why do they do this? Some studies suggest that the mass gathering is part of a survival strategy: The birds are learning about threats and seem hesitant to revisit any spot where they've encountered a dead crow, even if food is plentiful there.

4. Crows have caused blackouts in Japan.

Since the 1990s, crows have experienced a population boom in Japan, where—not coincidentally—delicious garbage is more plentiful than ever before. This is bad news for power companies. Urban crows like to nest on electric transformers and will often use wire hangers or fiber-optic cables as building materials for their nests. The result was an epidemic of crow-caused blackouts in major cities around Japan: Between 2006 and 2008, the corvids stole almost 1400 fiber-optic cables from Tokyo power providers, and according to the Chubu electric company, crows are responsible for around 100 power failures per year in their facilities alone.

To fight back, Chubu started installing artificial "love nests" in 2004. Made with non-conductive resin, the nests are placed on company towers high above the power lines, where the birds are unlikely to cause any trouble. The strategy seems to be working: 67 percent of the faux nests are currently in use, making life a lot easier for Chubu employees.

5. Proportionally, some crows' brains are bigger than yours. 

According to McGowan, crows are "smarter than many undergraduates, but probably not as smart as ravens."

Crows are so smart and so good at improvising that some zoologists admiringly call them "feathered apes." And yet, from a primate's perspective, crow brains might look puny. The New Caledonian crow, for example, has a brain that weighs just 0.26 ounces. But relative to its body size, that brain is huge, accounting for 2.7 percent of the bird's overall weight. By comparison, an adult human's three-pound brain represents 1.9 percent of their body weight.

Of all the living birds, crows, ravens, and parrots have the biggest brain-to-body size ratios. And in lab experiments, these avians show a degree of cognition that puts them on par with the great apes. In fact, research has shown that they have a much higher density of neurons in their forebrains than primates do. The amount of neurons in this region is thought to correlate with a given animal's intelligence. Theoretically, having more neurons translates to better cognitive reasoning.

A 2020 study looked at whether crows, like humans and great apes, can demonstrate consciousness. Crow brains lack a cerebral cortex, where most of the primate brain's conscious perception happens. Researchers tracked the brain activity in two crows as they performed different tasks, and discovered that they could perceive sensory input—suggesting that there is much more to understand about the evolution of consciousness.

6. Crows have regional dialects.

Apart from the famous caw, caw noise, crows emit a number of other sounds. Each one sends out a different message; for example, cawing can be used as a territorial warning or a way for crows to signal their location to relatives.

This avian language isn't homogeneous; two different populations of crows may have slight differences. As ornithologist John M. Marzluff and author Tony Angell noted in their 2005 book In the Company of Crows and Ravens, the calls these birds use "vary regionally, like human dialects that can vary from valley to valley." If a crow changes its social group, the bird will try to fit in by talking like the popular guys. "When crows join a new flock," Marzluff and Angell wrote, "they learn the flock's dialect by mimicking the calls of dominant flock members."

7. Some crows can read traffic lights.

In Japan, carrion crows (Corvus corone) use cars like oversized nutcrackers. The birds have learned to take walnuts—a favorite treat—over to road intersections, where they put the hard-shelled snacks down onto the pavement. The crow then waits for a passing vehicle to smash the nut, after which it will swoop down and eat the delicious interior.

It's a risky trick, but the crows aren't usually run over because (unlike some people) they've figured out what traffic lights mean. Carrion crows wait until the light turns red before flying down to place the un-cracked nut on the road. The second the light goes green, the crow takes off to watch the nut get run over from afar; it will even wait for the next red to scoop up the nut's insides.

This behavior isn't limited to just one corvid species: American crows have been observed doing the same thing in California.

8. Crows can recognize your face—and hold a grudge.

You don't want a crow for an enemy. In 2011, a team from the University of Washington published a remarkable study about the brainpower of local crows. The researchers' goal was to figure out how well the birds could identify human faces. So—in the name of science—they went out and bought two Halloween masks: One resembled a caveman, the other looked like Dick Cheney. It was decided that the caveman getup would be used to threaten the birds, while the Cheney mask was relegated to control status.

At the five sites, a scientist donned the caveman mask before catching and banding some wild crows. Getting trapped is never a fun experience, and upon their release, the ex-captives loudly "scolded" their assailant with a threatening caw. Seeing this, other birds who had been sitting nearby joined in the fray, swooping down to harass the neanderthalic visitor. Over a period of several years, both masks were regularly worn by team members on strolls through all five test spots. Without fail, the caveman mask was greeted by angry scolds and dive-bomb attacks from crows—including many who'd never been captured or banded—while the birds largely ignored the Dick Cheney mask.

Amazingly, the caveman disguise continued to provoke a hostile response five years into the experiment—even though the team had stopped trapping crows after those first few site visits. And some of the birds who antagonized the mask-wearer weren't even alive back when the whole thing started. The younger crows couldn't possibly have seen the imitation caveman grab an acquaintance of theirs—but they scolded it anyway. Clearly, the grudge had been passed on; birds were still attacking the mask as recently as 2013.

The moral of this story? Mind your manners around crows. Because if you mistreat them, they won't forget you and neither will their friends—or the next generation.

9. New Caledonian crows make and use tools.

Lots of non-human animals, including chimpanzees and orangutans, create useful implements which help them survive in the wild. The New Caledonian crow (Corvus moneduloides) is one of only two species on the planet that can craft its own hooks in the wild. The other is called Homo sapiens. The South Pacific avian uses the hooks—which are made from pliable twigs that the crows bend using their beaks and feet into a J-shape—to extract insects from tight crevices.

Another surprising attribute is this species' bill. Unlike virtually all other birds, the New Caledonian crow has a bill that does not curve downwards. For years, the quirk went unexplained, but scientists now think that the avian's unique beak evolved to help it grasp tools more easily, as well as to better see what the tool is doing.

The New Caledonian crow isn't the only implement expert in the corvid family. In 2016, scientists at the University of St. Andrews demonstrated that the ultra-rare Hawaiian crow, or ‘Alalā (Corvus hawaiiensis), is similarly adept at using and modifying tools.

10. Crows fight off predators by ganging up on them.

Crows have to deal with a menagerie of predators, such as hawks, owls, coyotes, and raccoons. To ward them off, the corvids exploit the fact that there can be strength in numbers. Upon seeing a would-be attacker, crows are known to gather, with some groups consisting of a dozen birds or more. Individual crows then swoop down to deliver passing blows with their beaks, often inflicting serious bodily injury in the process. If all goes well, the target will back off—though it may kill a few of the dive-bombers before they retreat. Corvids are by no means the only avians that mob would-be attackers. Swallows, chickadees, and even hummingbirds have all been documented doing this. In fact, crows are sometimes at the receiving end of mob violence as smaller songbirds often feel threatened by them and lash out collectively.

11. Crows understand a thing or two about impulse control.

A 2014 study shows that at least some corvids can resist the urge for instant gratification—if you make it worth their while. The research was led by University of Göttingen graduate student Friederike Hillemann, whose team assembled five common ravens and seven carrion crows. Through careful note-taking, the scientists figured out what the favorite meal items of all 12 animals were. Then the experiment began.

With an outstretched hand, one of the researchers gave each of their birds a morsel of food. Then, the animals were shown a different piece of grub. The corvids were made to understand that if they liked the second option better, they could swap snacks—but only if they were willing to sit patiently for a certain period of time first. If a bird ate the original treat during that stretch, it forfeited the chance to trade it for a new one.

Hillemann's results showed that the crows and ravens didn't mind waiting around for an improved snack option. As such, a bird with a piece of bread was content to sit quietly if it knew that some fried pork fat would eventually be gained in the trade-off. However, if that same bird's second choice was another piece of bread, sitting tight would be pointless. So understandably, corvids who were put in this kind of situation tended to go ahead and eat whatever they'd been given. Why wait for more of the same?

12. YOU CAN CALL A GROUP OF CROWS A MURDER, BUT SOME SCIENTISTS WOULD RATHER YOU DIDN'T.

According to the Oxford English Dictionary (OED), the correct term for a group of crows is a murder, an expression bird-watchers and poets have been using since at least the 15th century, which the OED speculates may allude "to the crow's traditional association with violent death, or … to its harsh and raucous cry." But maybe it's time to come up with a replacement. McGowan hates the phrase "murder of crows." To him, it only feeds the public's negative outlook on the animals. "These birds aren't a gang of nasty villains," he wrote in the book Birdology. "These birds are just birds." McGowan would also have you know that American crows rank among "the most family-oriented birds in the world."