Wild Things
Slate’s animal blog.

Nov. 30 2015 3:57 PM

Wild Dogs Are Vicious Killers With a Surprisingly Generous Social Life

When people think of the animals of Africa, they worry about getting crushed by elephants or chased across the savannah by a pride of lions. Maybe they fear getting Mufasa-ed by wildebeest or buffalo, envenomated by black mambas, gored by hippos, or drowned by crocs.

But this is silly. The crown of bones for the most deadly animal in Africa has to go to the cuddliest looking critters of the bunch—the painted dogs.  


The African painted dog looks similar enough to the tuft-tailed mutt you grew up with, but I promise you, this canine doesn’t wear Christmas sweaters. Alternately called the African wild dog, Cape hunting dog, ornate wolf, and about half a dozen other combinations of those words, Lycaon pictus is more formidable than its big ears and calico coat let on. Some just call them “the devil’s dogs,” and maybe not without cause.

“One of the reason’s why people think painted dogs are ruthless killers,” says Esther van der Meer, scientific advisor for Painted Dog Conservation, “is because of the way they disembowel their prey.”

When a scientist uses the word disembowel, it’s my duty as your Wild Things scribe to lean way in. So if you have kids or vegans nearby, you may wish to relocate or put on some headphones. Because it’s about to get all nature-red-in-tooth-and-claw up in here.

I spent a week hanging out with the crew of WildEarth.tv, a team that live-streams the happenings of the African bush onto the Web twice a day, every day. Its show Safari Live broadcasts this week during Nat Geo Wild’s Big Cat Week. (Full disclosure: Nat Geo Wild paid for my travel and lodging. I picked up the tab for the malaria meds.)

While the rest of us are forgetting to put cover sheets on our testing procedure specification reports, the crew members of WildEarth.tv are tracking leopards by urine, sticking their heads into hyena dens, and monitoring the House of Cards–like power struggles between prides of lions. And while they literally see the Big Five on a daily basis, many of them seemed most impressed by the wild dogs.

Perhaps this is because they get to experience wild dogs as they truly are—both bloodthirsty carnivores capable of stripping much larger animals down to the bone but also highly social pack animals with bizarre hierarchies that would deeply offend any Ayn Rand fans. Each side of their biology supports the other. You cannot separate the two.

Take this clip of a wild dog hunt that WildEarth.tv shot during last year’s Big Cat Week. I’ll tell you right now that it terminates in one of the bloodiest kills I’ve ever seen—the dogs eviscerate a pregnant impala and carry away its kicking fetus while the cameras roll from just a few yards away. But we can’t allow the gruesomeness of the act to overshadow the brilliance with which it is constructed. More on that in a moment. For now, just watch.

Take a deep breath. You good? OK, let’s continue.

“As much as this is not a pretty sight, it is a quick way for prey to die,” says van der Meer, “especially compared to the hours it can take lions to kill prey.”

Big cats tend to go for an animal’s windpipe, a method that can fail if the hold isn’t just so. Covering the nostrils and mouth is another way to go. And at least one pride of lions has learned how to take down elephants this way: First they slice through the elephant’s hamstrings, then collapse it with their weight while other lions clamp down on the trunk and attack the throat. All in all, you could watch Stand By Me in its entirety in the time it takes to a lion pride to suffocate an elephant.

Cheetahs, for instance, are famously prone to overheating, so you’ll often see them sitting atop a prey animal mid-kill, panting while the doomed creature kicks pitifully at the dust. Not so with the wild dogs. Because they’ve evolved to withstand high body temperatures, they have no need for a post-chase cool-down. That means that if you’re ever caught by one, you’ll likely be in half a dozen stomachs before you even know you hit the ground.

But at least you can rest assured that your carcass will be shared! Van der Meer explains that wild dogs hardly ever show aggression toward one another, and especially not while feeding. And according to studies, wild dog pups are given priority at kills as soon as they’re old enough to join the hunt. In fact, near the beginning of the video above, you can watch as one of the adult dogs leaves the hunt to bring in reinforcements, including a bunch of cuddly little pups. And this all-for-one, one-for-all attitude extends beyond the young’uns.

“Painted dogs are incredibly social creatures that take communal care of not only their puppies but also the sick and injured,” says van der Meer.

At least you can rest assured that your carcass will be shared.

Courtesy of Pieter Pretorius

Packs can consist of anywhere between six and 20 animals and are usually headed by an alpha pair. When either member of an alpha pair dies, the pack splits up into two single-sex adult groups. Strangely, a male from the youngest sexually mature cohort, rather than the oldest, accepts alpha dog status of the male group. Alpha females retain their status for life.

This dissolution, called pack fission, allows for a peaceful transition of power while also diversifying the gene pool. Over the course of a year, each pack’s dynamic will change as new pups are born and sexually mature males join in the hopes of breeding.  

Roger Burrows, of AfricanWildDogWatch.org, has a whole paper on the process, but here are a few notes that highlight the crazy inverted hierarchy of these animals: Any time alpha male status is transferred, the former alpha (if he’s still alive) remains in the pack peacefully. If the group finds orphaned males, they will adopt them. Once the orphans are sexually mature, one of them will assume control of his foster pack as alpha—again, all of this without any violence. If two breeding pairs have pups in the same season, the subordinate pair’s pups have priority over the alpha pair’s pups at kills. In other words, African painted dogs live by a code that’s basically the opposite of everything you know about capitalism, “the law of the jungle,” and your high school cafeteria.

So yes, we’re talking about an animal with the strongest bite force quotient of any living Carnivora, an animal with massive premolars designed for crunching through bones, an animal that hunts with one of the highest success rates of any predator on earth. But these are not wantonly wielded weapons of destruction. They are highly evolved tools that have allowed an animal the size of a border collie to survive on a continent full of horns and teeth and claws.

Unfortunately, despite millions of years of evolutionary fine-tuning, the future of the African paint dog looks dire. According to van der Meer, fewer than 650 breeding pairs remain. Persecution by humans is one problem, as livestock owners have tended to view the predators as vermin and shoot them on sight. The dogs are also killed unintentionally by snares, struck by vehicles, and laid low by diseases such as rabies and canine distemper. And every death counts.

“Once a pack has lost several members and pack size becomes critically low, a whole pack can become extirpated due to a decrease in hunting and reproductive success,” says van der Meer.

But far and away, the biggest problem facing Lycaon pictus today is habitat loss. The whole of the remaining population now survives on just 9.4 percent of the species’ historical range. The International Union for the Conservation of Nature has listed the wild dog as endangered since 1990—and the population is still decreasing. African wild dogs are a species in its twilight, and one often ignored by the flashcards and picture books we use to teach our kids about wildlife.

From peaceful power transfers and pup-rearing to the drive-by disembowelings that have made the animals infamous, the African wild dogs’ complexity just makes the predators all the more magnificent.

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Nov. 28 2015 11:35 AM

The Good Dinosaur Should Have Let Dinosaurs Evolve

The Good Dinosaur is a weird little movie. Despite the animated film’s immense budget and the sweeping vistas of Idaho, Wyoming, and Utah that serve as the backdrop for the alternate history tale, it’s really a small, simple story of “a boy and his dog,” only this time the boy is a dinosaur and the dog is a boy. All the plot points will be familiar to anyone who has watched The Lion King, Finding Nemo, Old Yeller, or White Fang, yet the familiar elements manage to come together well in this dinosaurian mashup of a well-worn yarn.

But there was one fundamental aspect of The Good Dinosaur that kept grating against the scientifically focused part of my brain. The movie’s opening conceit is that the mass extinction of 66 million years ago never happened. The massive asteroid that sparked the great die-off missed, and so the reign of the nonavian dinosaurs continued unabated. Pixar basically bought itself another 66 million years of evolutionary history to play with and then it squandered the opportunity.

There are plenty of paleontological nitpicks to be made about the movie. Poor Arlo, our herbivore dinosaur hero, was given forelimbs that bend the wrong way, in the opposite direction from every other dinosaur and four-limbed vertebrate that has ever lived. And while I can get that the move was done for aesthetics, the way the Tyrannosaurus cowboys gallop borders on disturbing. The carnivores keep their torsos stiff as the rest of their body bounds along, almost as if they’re riding mounts which happens to be themselves. The list could go on, to which the natural and reasonable response would be “It’s just a children’s movie!” But I still can’t shake the feeling of disappointment that Pixar decided to give us goofy, cartoonish versions of dinosaurs based on outdated notions from the 20th century, rather than actually playing out the consequences of the world it created.

The movie’s mammals underscore the problem. Hiding in the nooks and crannies of The Good Dinosaur’s world are little fuzzballs that don’t belong to any known species. They’re supposed to be new critters that evolved under the claws of the dinosaurs. This fits what we would expect if Arlo’s kind stayed large and in charge for another 66 million years. Even though mammals during the real Age of Dinosaurs diversified into an array of forms similar to today’s flying squirrels, beavers, anteaters, and more, the largest, Repenomamus, was only the size of a badger. And while the movie applies this effect unevenly—humans would never have evolved if dinosaurs remained dominant—the novel minibeasts Pixar created for The Good Dinosaur are a fun extension of the film’s setup. So why weren’t the same evolutionary consequences applied to the dinosaurs?

The Good Dinosaur’s major characters bear more resemblance to the giant models the Sinclair Oil Company floated down the Hudson for the 1964 World’s Fair than what paleontologists currently know about the creatures. Arlo and his family are variations on the standard “Brontosaurus” body plan, the eccentric collector Forrest Woodbush is a Styracosaurus, Butch and his family are Tyrannosaurus, and so on. So even though mammals have continued to adapt and evolve during the 66 million years of this alternate history, dinosaurs have either stagnated or reverted to previous body types while becoming smarter. Unfortunately, we never meet a dinosaurian naturalist to explain what the heck is actually going on.

As far as I can tell, evolutionary imagination was sacrificed in favor of nostalgia. This is obvious from the opening scene. Long-necked sauropods sprawl in a Cretaceous bog, lazily chewing soft vegetation as they slowly raise their necks from the quagmire. Given that Pixar is currently back under the Disney umbrella, this has to be a callback to Fantasia or the ExxonMobil-sponsored Universe of Energy ride in Epcot Center, which I badgered my parents to take me to see the moment I first stepped foot in Disney World. Even though Pixar movies are ostensibly for today’s kids, they’re shaped by the experiences of their parent’s generation, and that includes dopey-looking dinosaurs.

Maybe the creators of The Good Dinosaur decided that inventing new dinosaurs, as they should have done, would be too jarring. They may have thought that we can only recognize dinosaurs as what they were, but not think of them as real animals subject to evolutionary pressures just like every other organism. (And maybe that has something to do with why the uber-religious are ruffled by the fact that birds are living dinosaurs.) But imagine the world Pixar could have created. We now know that many dinosaurs—even the fearsome tyrannosaurs—had fluffy plumage. Given how many of the movie’s dinosaurs worry about the onset of winter, wouldn’t it have made sense for them to evolve downy coats to help insulate them from the biting chill of the high Western plains? Or, given all the farmwork involved in the movie, why not have descendants of Velociraptor-like dinosaurs that evolved to use claw and beak to make tools the way some crows do today?

I don’t know why Hollywood is afraid of the new dinosaurs and feathered dinosaurs in particular. This isn’t unique to The Good Dinosaur. We’ve been told that the dinosaurs of Jurassic World couldn’t be brought into accord with science because it’d break continuity, even though it would have been easy enough to write a scientist explaining how bird DNA had replaced frog genes to plug all those holes in the de-extinction process. And now we have The Good Dinosaur, whose only feathery dinosaurs are a pack of hillbilly raptors who make Cletus the Slack-Jawed Jokel look like subtle satire by comparison. I don’t understand the impulse or the reasoning that dinosaurs must always serve nostalgia first. Some of them are still here, continuing to change as they flit about our world, but in film we seem to be more comfortable relegating them to the fetid swamps of childhood memory.

Nov. 24 2015 11:17 AM

Why We (and Google) Still Love Lucy

Today’s Google Doodle is a lovely animation celebrating the anniversary of the discovery of Lucy, a 3.18-million-year-old Australopithecus afarensis fossil at the Hadar research site in the Afar region of Ethiopia.

On Nov. 24, 1974, paleoanthropologist Donald Johanson and a student, Tom Gray, discovered a forearm bone on a walk back to their car after a long day of fossil hunting, a find that led to a two-week excavation and the discovery of hundreds of bones and fragments that made up 40 percent of a complete skeleton. They named it Lucy.


Since then, our knowledge of human evolution—and our family tree—has expanded greatly. We know of more than 20 different hominid species, including as many as eight in Lucy’s genus, Australopithecus. And yet, Lucy is still arguably the most famous specimen. Why?

At the time, Lucy was the most complete hominin fossil on record. It can be hard for casual observers to understand how scientists can announce a new species based on a skull, or even on a collection of jawbones, but Lucy could give us a real and easily comprehended glimpse into our past. She was the first to provide evidence that walking on two legs evolved before our larger brains. (And yes, Lucy is a “she.” While the story goes that her name came from the fact that “Lucy in the Sky With Diamonds” blared repeatedly in camp while Johanson and Gray celebrated their discovery, research determined that she was female based on her pelvic bone and sacrum.)

Today, Lucy’s fame makes her an important and valuable icon to help us understand other discoveries. In 2005, a team led by Yohannes Haile-Selassie found a partial afarensis skeleton at the Woronso-Mille research area less than 40 miles from where Lucy was discovered. At 3.6 million years old, “Kadanuumuu” is about 400,000 years older than Lucy, but he was quickly dubbed “Lucy’s great grandfather.”

Other notable afarensis fossils—Lucy’s kin—include the famous Laetoli footprints that a team led by Mary Leakey discovered in 1978 in Tanzania. These footprints indicated that afarensis had feet that were more like humans than apes and that they walked much like we did. And one year after discovering Lucy, Johanson found 200 specimens from at least 13 individuals that became known as the First Family.

Just last May, Haile-Selassie, a curator at the Cleveland Museum of Natural History, named a new species called Australopithecus deyiremeda that is notable because, at 3.3 million to 3.5 million years old, it was living in Ethiopia at the same time as afarensis. Lucy had family, and she also had neighbors.

Nov. 24 2015 9:00 AM

Cats’ Internet Antics Belie Their Inner Narcissism, and They’d Eat You if They Could

Excerpted from Cat Is Art Spelled Wrongedited by Caroline Casey, Chris Fischbach, and Sarah Schultz. Out now from Coffee House Press.

I don’t hate all cats. I like only one. Her name is Aligato.


Aligato is my neighbor’s cat, and even though she craps in my yard as if she owned the joint, I’ve come to enjoy her charms.

She stays out late, she prowls. One of her eyes is either gone or permanently shut because, well, she’s a bit of a brawler. When she does come on my porch, she always says hello and looks me right in the eye with her one good eye. She likes being petted, and she even comes when she is called. She is, in other words, a dog.

So my favorite cat—well, actually the only cat I like—is really a dog in a cat suit. The rest of them, the millions on the Internet, at my friend’s apartment in the city, in the cat lady’s house up the street, I do not like. It’s not that I hate them, it is only that I return their indifference. Cat owners lavish love on their pets and are convinced they are receiving something in return. What exactly are they getting back? A rub against the leg or hand? It means the cat has an itch, nothing more.

I asked Ben Huh, king of all Internet cats and the dark overlord of I Can Has Cheezburger, why, with all of the tropes, memes, and wild critters on the web, that cats came to rule. He said it was very simple.

“The Internet is a playpen for cats where you never have to smell or clean the litter box,” he said.

But why love something that won’t love you back, whether it is on the Internet or in your home?

“Cats are like having a teenager. They just look at you over and over and say, ‘Can I have more stuff?’ ” he said. “They don’t really do anything; they lay about, so it’s hard to tell cats apart from teenagers, except teenagers hang out at malls more. And yet people still love their teenagers. And their cats.”

I’m not unmoved by the sight of a cat on the Web playing the piano, but unless they are going to kick into a decent version of Chopin’s First Ballade, Op. 23, there is a going to be a limit to my amazement by this time.

All other domesticated animals that humans adore are working animals. It’s a historical fact that cats were once prized for their ability to eliminate rodents, their one domestic chore, but most cats I know are on strike, content with being on the Meow Mix dole.

Cats were domesticated not for their usefulness but because they were mooches and hung around humans, acting all cute and cuddly just for the snacks. Dogs save people, sniff out bombs, pull sleds, herd sheep, guide blind people. Cats are mostly good at finding a sunny spot in the apartment and doing a series of lazy stretches that would not pass muster in a beginner’s yoga class. On the Internet, the cat’s greatest hits usually show them doing stupid stuff involving aquariums, televisions, and mirrors, which aren’t really tricks so much as cats expressing their inner aggression and narcissism.

Yes, in most developed countries there are more cats than children, but as soon as we figure out how to train a 2-year-old to poop in a box and are able to leave them home alone for hours on end, you can bet those percentages will reverse.

Whenever cat lore comes up, their advocates will always mention that they were deified and mummified in Egypt, but let’s remember that those pharaoh cat lovers enslaved thousands to build cats’ pyramids, actual humans who were treated far less well. And throughout history, who were witches always hanging out with? Oh yeah, cats. The witch doesn’t want a friendly labradoodle around; she wants a black cat as a like-minded familiar as she goes about her evil deeds.

In popular culture, the first icons that pop to my mind catwise are Garfield, Catwoman, and Cat Stevens, all of whom have rather conflicted reputations. And who is the big star on the Web these days in the feline world? Oh yeah, Grumpy Cat has 8 million likes on Facebook, all for her specialty of giving mean looks to everyone, which frankly doesn’t strike me as remarkable—cats do that all the time.

I am not immune to the charms of the feline form. Cats, as the Internet has taught us, are cute because they are both ferocious and adorable. They are predators rendered in miniature with all the tools of a killer—fangs, claws, a mighty pounce when they are not too fat—but they are harmless because of their size. That means that their hunting instincts are now aimed at rodents, hapless amphibians, and bugs. But make no mistake: When they dream, they dream large, of the days when they and their ancestors ruled the earth, loping along, scanning for food and hitting the afterburners when they saw prey.

And if those dreams came true, if evolution reversed and they again became big and ferocious, the relationship with humans would both change and, in some ways, be the same. When you come through the door at the end of the day, your cat sees one thing: food. It knows that it is time to eat, and you will obediently get its kibble and put some nasty wet food on top because, well, you are its slave.

If cats suddenly woke up saber-tooth size, they would still see food when you walked through the door, except you would be dinner. You don’t like to dwell on it, but you know if they were big enough, they would snack on you as if you were a field mouse. They might toy with you a bit, letting you make a feckless attempt to flee before they gathered you back toward their hungry maw with a swipe of their paw.

Remember Timothy Treadwell, the guy who thought he was a friend to all grizzly bears in Grizzly Man? They were not his friends, as Werner Herzog, the director of the film, says in the narration. Looking at Treadwell’s filmed footage of his bear friends, he says, “I discover no kinship, no understanding, no mercy. I see only the overwhelming indifference of nature. To me, there is no such thing as a secret world of the bears. And this blank stare speaks only of a half-bored interest in food.”

There is no such thing as the secret world of cats, or if there is, they own you instead of the other way around. Be honest with yourself: How many times have you looked into your cat’s eyes and seen not the wonders of the universe but “a half-bored interest in food”? It’d eat you if it could, and seeing as it can’t, it just stares at you until you come up with something they can.

All the anthropomorphizing and speculating you do about what is in your cat’s little noggin? For naught. Your cat’s brain weighs under an ounce, is the size of an avocado pit, and contains just as many deep thoughts. Cats have mastered the art of looking wise, but that uses up all the gray matter they have—which reminds me of a boss I once had, but that’s a much longer story.


Cats are different than us. You and I might hear a songbird and delight in God’s creation. A cat will hear the same thing and do its best to kill and eat that bird, putting an end to the music and the creature that made it. Yes, they are expressing their inner, feral nature, but let’s face it, any animal that will kill a pretty bird singing a song is pretty damn gangster.

My dog Charlie, a blond lab and girl, by the way, chases squirrels but does not catch them, a perfect version of the suburban wild kingdom. Every night she waits by the door and has a single question when I walk in: “Am I loving you enough right now?” She stares right into my face as she all but breaks herself in wagging with excitement. When she settles down and I ask for a kiss, she will stop what she is doing—unless she is eating—and come over to me. She will look up at my face adoringly and slowly place one paw and then the other on my leg and hoist herself up and give me one delicate lick on the nose. And then she sits back down. When is the last time you saw a cat do that? Put that in your Internet browser and smoke it.

You could say it is because my dog has no taste in companions, to which I would say, exactly. What I want in an animal companion is blind loyalty, unconditional love, and steady adoration.

So, in my family, we are dog people. That does not mean that if someone dropped a box of kittens on our doorstep we would ignore their mewling or their helpless adorableness. We would find a way to help them survive and find homes, but not ours, because kittens inevitably become cats, and that’s where the problems begin.

I should say I don’t mind looking at cats on the Internet, in part because they are ubiquitous and can’t be avoided, and in part because I think that’s where cats should live, on the Internet, imprisoned by my browser and one click away from being banished.

So, my little furry friends, go forth and multiply. Infest every corner of the Web as is your nature. Chase that laser light, squeeze yourself into a glass bowl, freak out at the toy robot that your owner has set before you. YouTube is waiting, and people imprisoned in office cubes everywhere depend on you, cats of the Internet, to bring a moment of respite to the quotidian tasks that are on other applications minimized until the boss walks by.

We will continue to click because it is in our nature. We might even organize a film festival at a cutting-edge museum so that your splendors, your unique charms, can finally find the widescreen presentation and communal audience your charms deserve. But if we meet offline in the real world, don’t expect me to ask for an autograph. I’ve interviewed and written dozens of stories about famous people who are riveting on-screen. They are, with very few exceptions, huge disappointments IRL. And some are monsters, drunk on narcissism and transfixed by their own reflection in the faces of those who adore them.

You, cats of the Internet, may be hilarious and full of frolic when the camera is on, but once the lights go down and the set is struck, you are still a cat. I know who and what you are. As do you, Mr. Cat. Just don’t tell the others, and you will be fine.

This essay is reprinted by permission from Cat Is Art Spelled Wrong (Coffee House Press, 2015). Copyright © 2015 by David Carr.

Nov. 20 2015 5:53 PM

Homo Floresiensis—Our Hobbit CousinsEvolved From Homo Erectus

Every announcement of a new hominid species prompts questions and debate: Is it really a new species? What characteristics set it apart from known species? Where does it fit on the family tree? But few discoveries have been as head-scratching as that of Homo floresiensis, better known as the “Hobbit” species.

In 2003, researchers discovered a cache of fossils—partial skeletons of at least nine individuals—on the island of Flores in Indonesia. What made them remarkable was that the most complete remains belonged to a 30-year-old female who stood 3½ feet tall, with a brain the size of a chimp, and who lived only 18,000 years ago. How did these early humans get so small? Had they evolved from a larger early hominin? Did they evolve elsewhere and then come to Flores? Could they be merely abnormal Homo sapiens?


A study released Friday in the journal PLOS ONE argues that H. floresiensis is indeed a distinct species, one that evolved from Homo erectus. H. erectus is by far the most successful hominin species in terms of how long it lasted. It is believed to have evolved 1.9 million years ago and endured until some point within the last 100,000 years. Along the way, H. erectus spread from Africa to Turkey and Asia, may have been the first species to control fire, and made advances in the stone tool technology first employed by Homo habilis.

Japanese paleoanthropologist Yosuke Kaifu and his fellow researchers did an exhaustive study comparing 40 teeth of floresiensis to hundreds of teeth of other species, including Homo habilis and Homo ergaster from East Africa, a Homo erectus from Java, and two ancient Homo specimens from East Asia.

The teeth were similar in size to those of smaller modern humans, implying that H. floresiensis could be unusual examples of Homo sapiens, but the teeth included too many primitive traits for that to be the case. The scientists then determined that those traits were more in line with H. erectus than with the older Homo habilis or perhaps an even older Australopithecus series.

"For me, this work will turn the tide about the question of evolutionary origin of H. floresiensis," Kaifu told Live Science.

There is more significance to the study than just declaring that H. floresiensis is indeed its own species. Ruling out those ancient ancestors for H. floresiensis argues against the idea that a species before H. erectus might have migrated out of Africa. It is also in line with previous artifacts discovered on Flores. Mike Morwood, the archaeologist who discovered H. floresiensis in 2003, had previously found crude stone tools of the sort used by H. erectus, dating to 840,000 years ago.

As the authors conclude in the new study, "H. floresiensis is not evidence for unexpectedly early hominin dispersal into Asia but is more likely an example of considerably greater flexibility in hominin physical evolution as originally proposed."

Nov. 17 2015 10:15 AM

These Animals’ Breathing is Breathtakingly Bizarre

If your lungs are working properly, you probably don’t think about them all that much. They’re pink. There are two of them. Smoking makes them sad. What else is there, really?

Well, did you know your right lung is bigger than your left, which has to share space inside your chest cavity with the heart? The right one is also built up of three lobes, while the left has only two.


And while breathing in and out seems like the most obvious thing in the world, something we all have in common, a gander around the animal kingdom reminds us that life is anything but simple.

Consider the Fitzroy River turtle, a native of Australia. Turtles have lungs that pull oxygen out of inhaled air, just like you and I do, and yet lab tests show the juveniles of this species can stay underwater for at least 72 hours. How do they do it? They utilize a highly sophisticated gas exchange apparatus known as their butts.

I’m being serious. Fitzroy River turtles have tiny, specialized papillae lining the walls of their cloaca—the one-stop-shop turtles use for urination, defecation, sex, and egg-laying. These papillae act somewhat like the alveoli in our lungs do, siphoning off oxygen molecules and absorbing them into the bloodstream. These baby turtles breathe through their butts.

Things get even weirder when you look at other reptiles.

“Most snakes have only one fully functional lung,” says Harvey Lillywhite, author of How Snakes Work. Lillywhite, of the University of Florida, explains that most of the organs in snakes have become cigar-shaped over the millennia, and the lungs are no exception. As in humans, the left lung seems to have gotten the short end of the stick. The left lungs are so shrunken in some species of snake, in fact, that they’re considered vestigial, leftovers from a time when they used to serve more of a critical function.

There’s actually still a lot we don’t know about how animals breathe. But we’re getting closer to understanding thanks to a scientist named Colleen Farmer and her experiments with live alligators and disco fog.

Alligators have weird innards. They have “teeny, tiny hearts because they’re aquatic, ectothermic, sit-and-wait predators,” says Farmer, a comparative physiologist at the University of Utah. They don’t need big, strong hearts like endurance athletes. But their lungs are huge. Weirder still, the lungs are intricately connected to the pericardium, the sac that contains the heart, something you don’t see in other animals.

As she was dissecting an alligator one day, Farmer says, an explanation dawned on her: Each beat of the heart could be tugging on the lungs in such a way as to stir up the air already inside, effectively circulating air to more areas where blood vessels can grab oxygen. If true, this breath by heartbeat (so to speak) would be a handy trick for a predator that likes to sit very still for hours on end—it could literally hold its breath while waiting to ambush its prey.

Just one thing: How do you test the fluid dynamics of airflow inside the body of a reptile?

Well, if you’re Farmer, you concentrate disco fog vapor in an e-cigarette, attach it to some tubing, and shotgun the vapor into a live alligator. Using an endoscope, she could watch the fog roll through the gator’s respiratory system. (“How’s work?” asks Grandma at Thanksgiving. “Oh, you know, same old, same old.”)

Farmer found that, in two minutes of holding its breath, an alligator can circulate the same amount of oxygen throughout its lungs using this “cardiogenic flow” as if it were sucking in fresh air.

Bird lungs look nothing like alligator lungs or human lungs for that matter. Open up a bird and you’ll find air sacs that look like bubbles made out of pink Saran wrap. And there are tons of them! Air sacs that push up into the neck, air sacs extending into the wings, air sacs down by the tail.

“There are just air sacs all over the place,” says John Hutchinson, professor of evolutionary biomechanics at the Royal Veterinary College at the University of London. “Pretty much everywhere there isn’t other stuff, there are air sacs.”

And Hutchinson would know. This dude has dissected everything from ostriches to rotten penguins.  

Anyway, all of these air sacs connect to the lungs in a closed circuit. This means that when a bird breathes in, the air doesn’t just come in and out again. It flows through a one-way network of tubes that get smaller and smaller. This unidirectional flow is a far more efficient way to breathe than passing air in and out through the same routes and a system long thought unique to birds.

However, Farmer is finding that unidirectional breathing—not to be confused with Tenacious D’s “inward singing”—may be a lot more widespread than we thought. She found it in her alligators: Their heartbeat-driven breathing only works because their lungs have tiny valves that coax air in one direction. She has since rigged up respiration experiments with monitor lizards and green iguanas and shown that both are also capable of unidirectional breathing. Next she wants to look at tuataras, turtles, and amphibians to see how deep the deep breathing goes.

Of course, if amphibians are capable of unidirectional breathing, it may well be the least bizarre trick in their repertoire. Many amphibian species can breathe through their skin, wicking oxygen out of the air like the weird little mutants that they are. And salamanders are weirder than most.

“There’s tremendous diversity in salamander respiration,” says Hutchinson. “They go through metamorphic transition where they transform from gill-breathing larvae to lung-breathing adults.”

And then some species have just given up on the whole lung enterprise. These salamanders, of the Plethodontidae family, breathe entirely through oxygen absorbed through their skin and the roof of their mouth. Best of all, you don’t even have to travel to some deep, dark jungle to find a lungless sally. Just go to Indiana.

Even amphibians that don’t breathe through their skin breathe strangely. We breathe by creating negative pressure inside our chest to suck in air, sort of like how a turkey baster draws all those delicious juices into its bulb. But frogs go the opposite way, says Farmer. They take two or three little gulps of air into their mouth, plug up their nostrils, and then shove that air down into their lungs.

Of course, birds, reptiles, and amphibians don’t have a monopoly on weird breathing. Mosquito larvae live underwater but breathe air through what can only be described as a butt snorkel. And a predator of mosquito larvae, the diving bell spider, is able to spend much of its life underwater by keeping air bubbles attached to its chest with tiny, hydrophobic hairs.

Mammals also have some fascinating representatives. Arctic ground squirrels go so stone-cold when they’re hibernating, you can seal them inside jars of noxious gases without making them stir.

Walruses and other marine mammals can store a ridiculous amount of oxygen in their blood and muscle thanks to enhanced levels of hemoglobin and myoglobin.

“It’s their own on-board scuba tank,” says Shawn Noren, an associate research scientist at University of California, Santa Cruz.

Male walruses also have large air sacs in their head and neck that they inflate during mating—“I guess the females find them sexy,” says Noren—though the floaties may also be used in the water for buoyancy.

Understanding how respiration works could change the way we think about how and why our ancient ancestors first made the lurch from sea to shore—and in some cases back again. In fact, whales—marine creatures that evolved from terrestrial creatures that evolved from marine creatures—may have the most bizarre breathing apparatuses of all. Through millions of years of evolution, their windpipes migrated into blowholes in the middle of their backs. Breathtaking.

Oct. 30 2015 5:46 PM

Stressed-Out People Love UberKITTENS, but Do These Programs Stress Out Pets?

Some people have pet allergies or really hate dogs, but in general nothing sounds better to stressed-out students or office workers than some playtime with puppies or kittens. So calming, so adorable. Hangouts with visiting dogs and cats have become increasingly popular in the United States, and while the benefits to humans seem clear, you might start to wonder how the pets are feeling about it. It's actually a controversial question.

You may have noticed that Thursday was National Cat Day.


To celebrate, ridesharing company Uber held the third years of its UberKITTENS promotion, where you can request that the company bring a batch of kittens to your office for 15 minutes. The first UberKITTENS was in three North American cities. The second was in seven. This year the event was held in 55. National Cat Day is scaling up.

Uber partners with local no-kill shelters in each city (they worked nationally with the American Society for the Prevention of Cruelty to Animals for the first two years of the program) to promote adoption and help socialize the kittens. The company has also run some UberPUPPIES events. Uber calls ahead to vet the locations it is bringing animals to and always has two representatives at each office the pets visit—one from the local shelter and one from Uber itself. "We make sure that the environment is safe," said Uber spokesperson Sarah Maxwell from inside one of the cat cars on Thursday. "The kittens really love it, they’re having lots of fun."

The trend has caught on in schools around the United States as well. Many colleges and universities bring pets to campus to help students de-stress during exams. These animals are often trained therapy dogs, and some schools even house therapy dogs on campus all year.

There are also regional programs like the Humane Society of Broward County's Snuggle Delivery service in southeast Florida. Similar to Uber's program, Snuggle Delivery is meant to increase the visibility of adoption initiatives and raise awareness about humane society efforts. For a $500 donation, HSBC will bring puppies or kittens to your office for an hour. (Uber collects a $30 fee for 15 minutes that it donates to its local shelter partners.) Snuggle Delivery even allows for on-site adoption. "We’ll bring all the necessary paperwork with us, and the pets will be spayed/neutered prior," Adam Goldberg, a spokesperson for HSBC, told the Huffington Post in March. UberKITTENS gives information to people interested in adoption so they can follow up with their local shelter. The company says that more than 20 kittens were adopted last year.

Emily Weiss, the ASPCA's vice president of research and development, told Slate in a statement that “The ASPCA supports creative ways to promote and find loving homes for animals within the community. Above all, the welfare of the animals is our top priority and as long as a safe and stress-free environment is provided, these types of engagements can be an enriching activity for both humans and animals alike.”

Overseas the topic is much more controversial, though.

The United Kingdom Royal Society for the Prevention of Cruelty to Animals shared a document with Slate dedicated to its “concerns regarding fundraising and rehoming initiatives which involve cats or kittens being transported from rescue centres/shelters into different offices.” It outlines potentially stressful conditions for the animals like unfamiliar environments and inappropriate handling and points out that the events “lack of benefit to animals” and could encourage “spontaneous/impulse adoption.”

In February, the tech site shinyshiny published a piece opposing UberKITTENS in Australia. Nicky Trevorrow, the behavior manager at U.K. feline charity Cats Protection, told the site, “Raised stress levels could affect feline health, causing conditions like cystitis and a lowered immune system, increasing vulnerablility to infectious diseases. Kittens already have a weaker immune system than adult cats."

It's a bummer. Do we really have to feel bad about wanting lots of kittens and puppies in our offices all the time? John Bradshaw, the foundation director of the Anthrozoology Institute at the University of Bristol in England and the author of Cat Sense and Dog Sense, said that it's positive to spread awareness about animals in need of adoption. "I’m in favor of animals in the workplace whenever possible," he said.

He noted, though, that events at offices can set "false expectations. What most of these shelters have is lots of adult cats that nobody wants, not kittens." He also raised concerns about potential health consquences for kittens and puppies. “The idea of using young animals who are not really adapted to this and who may find it stressful if the experience becomes overwhelming—I’m not in favor of that,” he said.

For now, these dichotomous ideologies seem to be resulting in on-location events with puppies and kittens being much more popular in the U.S. than in the U.K. It's so easy to think they just want my love. But the concerns linger. Daniel Mills, a professor of veterinary behavioural medicine at University of Lincoln in England, quickly responded to an email about these types of events. “Is this real? Sadly I guess it might be. This sounds like a really bad idea to me. So many physical and psychological risks.”

Oct. 29 2015 11:04 AM

Vampire Bats Can Walk, Jump, and Run on the Ground

It begins as a slow creep. One wingtip is placed in front of the other—left, right, left, right. Slowly, methodically, the vampire bat inches across the ground toward the sleeping tapir.

Vampire bats can stalk prey many thousands of times their own size, so one wrong move can mean a lost chance at a meal or worse, a hoof to the skull. Blood-feeding requires the stealth of a snow leopard, not the rash aerial acrobatics of the vampire bat’s insect-catching cousins. And so the vampire crawls.


From a distance of six inches, special sensors in the bat’s nose allow it to use infrared radiation to detect the heat of blood close to the skin. The only other animals with this superpower are few snakes like the pit vipers.

Once it zeroes in a hot spot, the vampire bat uses scalpel-like incisors to carve tiny divots in the tapir’s flesh. The bite is so fast and clean, the tapir doesn’t even stir in its slumber. An anticoagulant in the bat’s saliva (appropriately named draculin) causes the blood to flow freely. As the crickets and cicadas hum into the night, the vampire bat licks its lips and prepares to suck the lifeblood from another mammal.

But here’s where all the vampire lore gets it wrong. True vampires do not suck blood. They lick it.

“When they feed, I think they look rather more like a cute cat lapping up milk,” says Gerald Carter, a postdoctoral researcher at the Smithsonian Tropical Research Institute.

Whether it’s the lapping or the loping, there’s clearly a lot about the vampire bats that popular depictions like Bram Stoker’s Dracula and Vampire Bats (the made-for-TV movie) get wrong. Which is a shame, because vampire locomotion is fascinating—and their creeping is almost as creepy as the whole blood-licking business.

“Unlike other bats, [vampires] can walk, jump, and even run on the ground,” says Carter, who studies these animals in Panama.

What’s interesting here is that there are more than 1,300 known species of bats in the world. And precisely one of them is able to run. That’d be Desmodus rotundus, or the common vampire bat. We know this because of Dan Riskin.

Riskin is a man of many talents. He’s a respected bat expert, an adjunct professor at the University of Toronto Mississauga, and cohost of Discovery Channel’s Canadian science show Daily Planet. But he’s also the guy who put vampire bats on treadmills. I probably should have led with that.

Riskin has spent a great deal of time studying bat biomechanics on the ground. Most bat species do not do well under such circumstances. They are awkward and slow, easy pickings for a predator.

But where the others look like a fish out of water, the vampire is able to gallop like a spider-bunny.

By coaxing vampires onto tiny treadmills, Riskin found that the flying mammals could run at speeds of nearly 4.5 miles an hour. He suspects that they might be able to summon nearly twice that speed in a pinch. Like maybe if OK Go needed extras for a new music video.

“I think [the vampire gait] is a nice reminder that we move the way we do because of physical laws of stability and power, but also because of our evolutionary history,” says Riskin.

For example, squirrels and frogs developed a bounding gait because they were already on an evolutionary path guided by powerful hind limbs. Bats went in the opposite direction, giving up lower limb strength in exchange for powerful breast and arm muscles to command their wings. But then the vampire bat started to double back on that path.

“Vampires had the motor up front,” says Riskin, “so when they evolved a bounding gait it was forelimb-driven.”

This front wheel drive, as he refers to it, makes the vampire bat’s running stride “kinematically different from that of any other tetrapod.”

But running isn’t the only thing vampire bat wings are capable of. Powerful pectoral muscles also allow them to spring into the air to initiate flight from a standstill like a Harrier Jump Jet.

Other bat species do many more interesting things with their webby wings.

Bats in the genus Tadarida use their wings to swim. The Cheiromeles and Mystacinidae bats have slots on their sides that they can tuck their wings into to keep them out of the way when they’re resting or crawling. Bats of the Saccopteryx genus have little fanny-pack pockets on their wings, which scientists believe are used by the males to store urine, glandular secretions, and Mentos—everything you need to woo a lady bat.

Some bats use their wing as a sling to catch their babies as they’re born. Other species’ wings have blood vessels built to dilate when the bats need to cool off.

Bat biologists have identified more than 60 different ways bats use their wings besides flying. These include defense, hiding, courtship, grasping, grooming, and fanning. For instance, says Carter, most people don’t realize that bats catch insects in the air using their wings as nets.

There’s even a bat with suction cups built into its wings. It’s called Spix’s disk-winged bat (Thyroptera tricolor), it lives inside tents made of waxy leaves, and Holy Halloween, Batman, it’s my new favorite animal.

Clearly, we all could all stand to spend a little more time around these wonderful, wingèd beasts. Thanks to a partnership with the Organization for Bat Conservation, Carter has set up a citizen science project that allows you to watch a captive population of vampire bats and log what you see. He calls it Vampcam, and after spending way too much time there one night, I can tell you it is all kinds of addictive.

Stick around long enough and you might just see a bat take a buddy under its wing and regurgitate a blood meal—which is basically the fun-size Snickers of the vampire bat world. Trick or treat!

In memory of bat expert Michael J. "Mick" Harvey, who this summer was called to the great roost in the sky.

Oct. 26 2015 3:11 PM

Hung Like a Howler Monkey

Just hours after stepping off the plane in Costa Rica, I was confronted with my first pair of monkey testicles.

My wife and I were on our honeymoon, our destination a spa and hot springs at the foot of the Arenal Volcano. I was anxious to get away from the city we flew into, San Jose, as quickly as possible, mostly because I wanted to see some wildlife. And then, less than an hour’s ride from the airport, our bus driver pulled over so that we could snap a few pictures of a monkey. A mantled howler monkey, to be precise.


I remember being disappointed upon looking out my window. The monkey was straddling a power line stretched across the mountain road. Not exactly the candid wilderness shot I was hoping for, but I pulled out our fancy new camera all the same. And that’s when I saw them.

Huge, white testicles—slung over the side of the power line in a way that recalled a few choice original verses of the children’s song “Do Your Ears Hang Low?

Forget about the beaches and the all-inclusive dining and the couples massage—I knew right then, staring down the barrel of two of the biggest, baddest gonads I’d ever laid eyes on, that we had come to the right place.


Courtesy of Jason Bittel

Most people probably don’t think about testes when they see the words howler monkey. The animals are known for having one of the loudest calls in nature, a grunting, vibrating cacophony that sounds like an enormous, angry bullfrog trapped in a trash can.  

But now, in what very well may be the most fun scientific paper of the year—the veritable chocolate-in-my-peanut-butter moment of 2015—scientists have managed to bring these two aspects of howler anatomy together in a study that investigates the relationship between vocal tract size and testes dimensions.

Naturally, they’re calling it the “calls and balls” paper.

“Of course, you can only say that so loud at the university,” says Leslie Knapp, a primatologist and chair of the anthropology department at the University of Utah.


At the base of the calls and balls paper is a bunch of data that doesn’t seem to be related to anything. Knapp and her co-authors worked with zoos to conduct testes volume measurements, analyzed recordings of howler monkey calls, and traveled to museum collections around the world to measure a particular bone found in howler monkey throats. Called the hyoid, this large, hollow structure acts like a resonating chamber, which amplifies the primates’ primal screams.

Anyway, it’s when Knapp and company put all of this information together that some mighty interesting correlations started to emerge.

For starters, howler monkey species with larger hyoid bones were able to create vocalizations with a deeper pitch. This part isn’t so surprising. Howler monkeys produce a bass pitch comparable to animals of much larger body sizes, such as red deer and elephants, and in general, larger vocal chambers can produce deeper sounds.

Much of the howler monkey’s characteristic croak is thanks to the hyoid bone. Humans and many other animals have hyoids, by the way, but none are so big and hollow as the howler’s. Magnetic resonance images of the howler’s throat also reveal extremely long vocal folds for an animal of its size. Some species’ folds are more than two-and-a-half times the length of a human’s.

It’s thought that male howler monkeys use this apparatus and the hoots it produces to guard territory from neighboring troops. Deeper bellows tell rivals that they’re dealing with a big monkey who doesn’t take any guff. Presumably, says Knapp, this also helps the male ingratiate himself with the ladies.

Now, this brings us to the second part of Knapp’s study. You might think that the howler monkey species with the largest hyoids—the biggest badasses, as it were—would have the biggest balls. But you would be mistaken.

“To make a long story short, what we find is that when males have a large hyoid bone, they also have smaller testes,” says Knapp.

That strapping howler I saw on my honeymoon? Turns out, this species (Alouatta palliata) had the smallest hyoid bones of any howler species surveyed but the largest testes. (To that, I can teste-fy.) (Sorry.) And we’re not just talking about a little bit bigger. The mantled howler’s testes are close to six-and-a-half times as big as the red howler featured in the video above.

To understand what all of this might mean, Knapp says you need to look at yet a third correlation found in the paper—the fact that howler monkey species with larger hyoid bones tend to have fewer males per troop.

This is important because group size and composition can tell you a lot about an animal’s anatomy. Humans, for instance, have relatively small testicles for our body size when compared to other closely related primates, such as chimpanzees. Knapp says this is likely because chimps live in multi-male/multi-female groups where everybody’s competing with everyone for reproductive rights. Thus, chimps have evolved big, honking testicles that produce tons of sperm in the hopes that this will give them an advantage over their rivals. Male humans, on the other hand, don’t have to invest as many resources into competitive sperm thanks to the benefits of monogamy.

Getting back to the howlers, Knapp says what the calls and balls paper seems to show is an evolutionary tradeoff. Each howler monkey species displays a different strategy of resource allocation. Some, like the mantled howler monkey, whose picture has been up on my computer all day and which my wife keeps laughing at, invested in enormous testicles to help them pass on their genes. Others blew their evolutionary wad on raucous hyoid bones, the better to impress females and keep other males at bay.

But wait, you may be wondering, why wouldn’t some monkey invest in both big balls and deep calls? After all, if deeper, Barry White–like vocalizations help you get laid and larger testes increase the chances of fertilization, wouldn’t it behoove the howlers to go big on both?

“If it was possible for males to have large testes and also large hyoids, we would have observed that in the study,” says Knapp. “It really seems to be one or the other.”

Knapp says this is probably because either route requires a vast amount of limited resources, and with all the things a howler must deal with in the wild—finding food, avoiding predators, fighting off rival males—there simply aren’t enough resources for the howler to have it all.

Of course, the calls and balls study is far from the final word on the teleology of howler testes. For starters, Knapp says they’d like to do genetic tests within species to determine whether deeper calls result in more offspring. (Hyoid size and call pitch vary within species, too, mind you.)

Furthermore, these are only a few of many potential variables involved in sexual selection. And all you have to do is look at the pictures I took of howlers on my honeymoon to spot another. I mean seriously, why would a monkey covered in thick, dark fur have a scrotum that looks like it’s been waxed and bleached?

“Maybe if the females aren’t impressed with the male’s vocalization, they can look at the testes size,” says Knapp, humoring me. “Or maybe it looks scary to another competing male.” (Or it may be that bald, pale testicles contribute to temperature control—there are a lot of theories about testicle evolution.)

Holsters for sperm, indicators of fitness, and maybe even dangling devices of intraspecies intimidation—I’ll bet you never look at testicles the same way again.

Oct. 16 2015 11:10 AM

Vampire Birds Thirst for Blood

Ticks, leeches, mosquitoes, vampire bats—when it comes to creatures that live by the vein, these are the usual suspects. But what if I told you there was a little blood-slurping birdy more diabolical than all of those guys put together?

Scientists call it Geospiza difficilis, but you can call it the sharp-beaked ground-finch or vampire finch for short.  


Unlike bald eagles, harpy vultures, horned owls, and all the other big, scary birds that eat meat, the vampire finch looks like an animal that could be found at your backyard feeder. It weighs less than an ounce, has no vivid colorations or vicious talons, and generally just looks like any one of a dozen species flitting across your neighborhood as we speak.

Fortunately for all the birds of suburbia, vampire finches live only on the Galapagos Islands. It’s likely that the remoteness and harshness of this locale are what has driven the birds to draw blood. Their prey is boobies and other large seabirds that may be 50 times the finches’ weight.

“The Galapagos have an environment that fluctuates tremendously, and the birds go through droughts where there’s just not a lot to eat,” explains Ken Petren, an evolutionary ecologist and dean of arts and sciences at the University of Cincinnati.  “And it’s in that context that we see birds being very creative about what they can try to eat.”

Of course, what strikes an evolutionary ecologist as creative, the rest of us would probably call horrific. That’s because the vampire finch isn’t the least bit nice about its bloodletting.

Vampire bats have teeth so surgically sharp, their victims can sleep through the ordeal. Mosquitoes and ticks anesthetize your skin before they suck. Leeches are aided by the numbing effect of cold water. Some of these bloodsuckers can go unnoticed indefinitely, so polite is their disposition. Who, us? Why, we wouldn’t think of imposing!

But the vampire finch of the Galapagos’ Wolf Island just hops right up onto a blue-footed booby’s back and jams its sharp beak into the seabird’s skin again and again until blood rains down. And once the vein is open, more finches arrive to the party like that blood-rave scene in Blade.

Why the boobies endure the abuse is up for debate. It might be that the boobies have no choice—Petren says Wolf Island has the highest density of vampire finches of any island, thousands and thousands of them in a very small area. It’s also quite far from the rest of the island chain, which means it’s extra remote. Add to that the fact that depending on the time of year, the boobies may be incubating eggs or caring for chicks, both of which the vampires are more than happy to peck at.

Interestingly, because the shells of booby eggs are too strong to penetrate using their beaks, the finches have developed a life hack that affords them yet another food source. Petren says the birds put their beaks on the ground in a sort of headstand, kicking the egg with their feet until it rolls off a cliff and breaks. Add a little Hollandaise and you’ve got Eggs Beelzebub.

Obviously, I don’t mean to give the impression that vampire finches are in any way evil. They’re simply animals making the best of a bad situation. On a string of islands in the middle of the Pacific, nutrients are hard to come by and an open wound might as well be an oasis.  

After all, the finches of the Galapagos are sort of famous for adapting. There are now more than a dozen finch species on the islands, and each has a special way of surviving. Some eat seeds, others eat insects, and some have devised several different ways to carve up cacti. There’s even a Tim “The Tool Man” Taylor finch that hops around the island grunting and using sticks, cactus spines, and other tools to pry insect larvae and spider eggs out of tree cavities.

Whatever their mode of survival, the finches of the Galapagos have over time developed beaks to match each enterprise. These birds are some of the first and most famous avatars of evolution, which is why they are sometimes called Darwin’s finches.

Vampire finches aren’t even the only blood-drinkers on the Galapagos. The hood mockingbird has also been known to nuzzle into open wounds on boobies and iguanas and ingest the afterbirth of sea lions. There are even records of hood mockingbirds trying to drink from blood dripping down the leg of human researchers.     

But the Galapagos don’t have a monopoly on bloodthirsty birds. Across the world, on the savannahs of Sub-Saharan Africa, there’s another vampire with an excellent common name—the oxpecker.

Until rather recently, oxpeckers were one of those species held up as an example of mutualism because it was thought that they provide an ecological service to large herbivores by eating their ticks, botfly larvae, and other parasites. The zebra gets rid of all its nasty hitchhikers while the oxpecker gets a fancy dinner full of protein—everybody wins, right?

Well, maybe. And maybe not. One study conducted in the scrubland of Zimbabwe found that cattle allowed to mingle with red-billed oxpeckers did not have significantly fewer ticks than those who had the birds relentlessly shooed away from them. (From the acknowledgements section of the paper: “Phineas Ndlovu, for scaring the oxpeckers.”)

What’s even more interesting, however, is that the paper also noted every pock, scab, and lesion on the cattle during the time of the study. And get this: The cattle that were allowed visits by the oxpeckers not only had a higher proportion of wounds that reopened or failed to heal, but they also had a higher number of wounds overall. This is because oxpeckers are notorious for pick-, pick-, picking their way into their hosts.

Do a quick YouTube search for oxpeckers, and you’ll find videos of these birds digging into hippo flesh, fighting over buffalo blood, and straddling the head of an antelope just to get at a face wound.

And then there’s this video of a giraffe with more red-billed oxpeckers on him than he has spots. There are birds on his head, neck, chest, back, and legs. Some comb his hair for dead skin and tick nymphs, others pluck off engorged adult parasites. But still more oxpeckers harry an open wound on the giraffe’s chest, dipping their entire heads into the red crevasse.

As the camera pans upwards, we see the bull has a stump where his left ear used to be. The narrator wonders if it isn’t the result of a tick wound opened up and never allowed to heal, thanks to the giraffe’s hungry avian hitchhikers.

No one seems to have observed an oxpecker actually creating a wound, as vampire finches are known to do. But the study mentions watching the birds deliberately peck at the place where a tick was attached to the cow’s skin without any apparent interest in eating the tick itself. It seems likely then that the oxpecker knows it can use a wound created by a parasite to open up a fountain of blood.

So if anyone is still looking for a scary costume this Halloween, I’d encourage you to pass over the werewolves, witches, and bats. Instead, be a little black bird with a beak built for bloodletting. They’ll never see you coming.