Slate’s animal blog.

April 22 2014 9:25 AM

Whales vs. Dinosaurs: What’s the Biggest Animal of All Time?

In 1841, in the early days of paleontology, the notoriously cantankerous anatomist Richard Owen, the man who would later coin the term “dinosaur,” stood before his colleagues at the Geological Society of London to announce the discovery of an enormous extinct reptile. The monster was represented by only a smattering of fossilized bone, but Owen nevertheless ascertained that the animal’s tail bones “equaled in dimensions a middle caudal vertebra of a full-sized whale.”

Owen’s name for the creature—Cetiosaurus, the “whale lizard”—played up the creature’s gargantuan size, and scientific showman that he sometimes was, Owen left the assembled scientists with the idea “that the surpassing bulk and strength of the Cetiosaurus were probably assigned to it with carnivorous habits, that it might keep in check the Crocodilians and Plesiosauri” that swam the same Jurassic seas.

Owen was almost totally wrong in his initial description, but I can’t blame him. The more-complete skeletons that would show Cetiosaurus to be a one of the long-necked, herbivorous, heavy-bodied sauropods hadn’t yet been found. At least the name is still on the mark. An adult Cetiosaurus was as long as a mature male sperm whale, around 52 feet.

Other sauropods grew even larger than that. Supersaurus, Argentinosaurus, and Diplodocus were the largest creatures to ever walk the Earth, stretching more than 100 feet from their pencil-like teeth to their sinuous tails. But that “walked the Earth” clause is important. While no terrestrial creatures ever approached these sizes, the largest whales can make sauropods look rather skinny. When it comes down to it, who can rightfully lay claim to the title of the largest animals of all time: dinosaurs or whales?

Video Advertisement

April 17 2014 11:17 AM

This Female Has All the Power—and the Penis

Separating two partners having sex is generally a bad idea. It is, after all, something few of us humans would appreciate. But when entomologist Kazunori Yoshizawa of Hokkaido University in Japan caught a pair of newly discovered cave insects in flagrante delicto, he pulled them apart. You know, for science. When he gave their tiny, translucent bodies a tug, he found the penis was so firmly embedded in the other insect that it ripped off its partner’s abdomen rather than dislodge.

An impressive penis, no doubt. But these things happen in insect sex. What made this penis a member of a special club, however, was the fact that it wasn’t on the male. Instead, Yoshizawa had discovered a new species of insect in which the penis belonged to the female and the male had a vagina. Thus far, this is the only species with this arrangement of genitalia yet discovered.

The insects, of the genus Neotrogla, were discovered several years ago in a Brazilian cave by biologist Rodrigo Ferreira at the Federal University of Lavras in Brazil. He’s a specialist in cave ecosystems rather than insects, so he sent them to entomologist Charles Lienhard in Geneva, Switzerland, for more detailed study. It was Lienhard who first discovered the penis on the female. They had to invent a new name for such a thing, and they called it a gynosome.

April 16 2014 10:24 AM

Hyenas Are Fascinating, Not Disgusting

I’ve gotten used to the reaction: “Really? Hyenas?” It’s almost always said with a mixture of surprise and thinly-veiled disgust, the same tone of voice that someone might use after finding out that you snack on rat intestines.

Yes, I spent seven years of my life studying spotted hyenas. I came out of the experience with a Ph.D. and a lot of entertaining stories about misadventures on the African savannah. But I also came away with the realization that hyenas have a serious image problem.


I blame The Lion King for much of the current hyena hatred out there. While I’m not shy about my love for animated movies, Disney really blew it on this one. The antics of Banzai, Shenzi, and Ed taught several generations of movie-goers that hyenas are scatterbrained scavengers prone to mistakenly chewing on their own legs. Entertaining and central to the storyline? Sure. Biologically accurate? Not even remotely.

But Disney was far from the first to slam hyenas—they’ve been maligned for thousands of years. In his History of Animals, Aristotle wrote that the hyena “will lie in wait for a man and chase him, and will inveigle a dog within its reach by making a noise that resembles the retching noise of a man vomiting. It is exceedingly fond of putrefied flesh, and will burrow in a graveyard to gratify this propensity.”

The situation hasn’t improved in more recent years. Hemingway bashed the hyena as a “hermaphroditic self-eating devourer of the dead, trailer of calving cows, ham-stringer, potential biter-off of your face at night while you slept, sad yowler, camp-follower, stinking, foul, with jaws that crack the bones the lion leaves …” There’s more—for a normally concise writer, he certainly went on and on here—but you get the point.

I admit that hyenas are a bit unusual. Female hyenas, rather than males, rule the clan. Each female also sports a pseudopenis, a seven-inch-long, fully-erectile clitoris that mimics a male hyena’s genitals with an accuracy that can stump even a seasoned biologist trying to tell the sexes apart. It’s no wonder that people have long thought hyenas were hermaphrodites; watching a hyena with a huge erection lie down and nurse cubs is a pretty confusing sight.

Hyenas' social IQ rivals that of most primates.

Courtesy of Kate Yoshida

Several other strange qualities probably don’t help the situation. Hyenas devour bone with unsettling ease, spend a lot of time splattered with the blood of their prey, and emit some very eerie whoops, giggles, and groans.

But their eccentricities don’t extend to ransacking graveyards, feasting on human faces, or snacking on their own body parts. Even many of the less nefarious accusations don’t hold up; for example, most hyenas actually scavenge very little, preferring to hunt their own food. They’re also about as far from stupid as you can get, with a social IQ that rivals that of most primates.

But does it matter what people think about hyenas? Should we care that cultural icons like Hemingway and influential brands like Disney promote these myths? Yes, I think so. I’d argue that millennia of misunderstandings have ingrained in us the idea that hyenas are animals to despise, a species that is expendable.

Hyenas may be biological oddities in many ways, but their quirks make them extremely valuable to those trying to understand the world around us. Their peculiar private parts challenge everything we thought we knew about sex roles in nature. Their incredible social skills are helping scientists figure out how and why our own brains evolved. Hyenas are also resistant to anthrax, making them an asset to the study of biological weapons.

With extinction on the rise, we must make difficult decisions about which species to save and how to use our limited conservation resources. Cute, charismatic animals like pandas and lions benefit from public adoration and generous donations, while less loveable animals like sharks and vultures face serious declines but have few advocates. Hyena populations are holding steady right now, but their future—like that of most large mammals—is uncertain at best.

If we want to preserve biodiversity, we’re going to have to set aside our personal biases and accept that even the weirdest species out there deserve at least a chance to thrive. You don’t have to fall in love with hyenas—or sharks, bats, or snakes, for that matter—but let’s not let our disgust determine their fate.

Not disgusting.

Courtesy of Kate Yoshida

April 14 2014 10:08 AM

Why Do Wolves Howl?

Of all the myths that dog the wolf, none is more widely accepted than the idea that wolves howl at the moon. Images of wolves with their heads upturned, singing at the night sky, are as unquestioned as a goldfish’s three-second memory or a dog’s color-blindness (both also myths). There are countless depictions of moon howling in faux Native American tchotchkes; the scene also appears in Jack London novels and at least one Los Angeles piano bar. This curious fiction has become so quotidian that even The New Yorker’s legendary fact checkers let “a long, lamenting howl at the orange moon” slide into print without a second thought.

The truth is that wolves—the real-life, Canis lupus variety—don’t howl at the moon. Scientists have found no correlation between the canine and Earth’s satellite, except perhaps an increase in overall activity on brighter nights. So how did the idea gain such traction, and what do wolves howl at?

April 10 2014 10:56 AM

Birds That Play Guitar

The young male zebra finch alighted on the nearest guitar and bounced across the mahogany fret board. He stumbled on the high E string—it was harder to grip against the polished wood. Then with an inquisitive side-glance, he sang a few bars, stretching his wings, and occasionally breaking off as if awaiting some sort of reply. Then he was finished. He defecated on the frets before uttering a final, insistent nasal call and flitting down to the sand below.

The guitar lay horizontal, propped up by a stainless steel cymbal stand. It had a white finish, perhaps the ideal paint job for concealing the bird droppings that peppered its otherwise gorgeous body. Every time a bird landed, took off, or hopped on its strings, the notes played through a nearby amplifier with preprogrammed digital effects: reverb, overdrive, digital delay.


The guitar is one of 14 chromatically tuned rock instruments—10 Gibson Les Pauls, four Gibson Firebirds—wired up inside the Barton Gallery at the Peabody Essex Museum in Salem, Mass.* They’ve stood there for four months, kept in tune for an orchestra of 70 zebra finches. The birds live in the space, which functions as a temperature-controlled aviary on the museum’s third floor for an exhibit closing on April 13.

Céleste Boursier-Mougenot.
Céleste Boursier-Mougenot.

Courtesy of Céleste Boursier-Mougenot

The birds’ ghost conductor is Céleste Boursier-Mougenot, a French composer and artist who has become a master at encouraging birds to make music. He does so by creating a kind of musical ecosystem. Called From Here to Ear, this is his 15th installation in a series of works spanning 15 years and cities around the world, from London to Berlin to Milan to Brisbane, Australia. (Click that last city for some amazing looks behind the scenes.)

In every city the exhibit has been wildly popular, and the prevailing question among its visitors has been the same: Do the birds know they’re making music?

“We think they do,” says Trevor Smith, the museum’s curator of contemporary art.

The birds are a mixed-age flock, about half males and half females. Three nest condos are hung from the ceiling, and the floor is covered with sand and patches of tall grass to mimic the finches’ natural environment—Australian grassland. Zildjian cymbals are filled with either water or food.

The floor plan of the aviary.
The floor plan of the aviary with specific guitar tunings.

Courtesy of the Peabody Essex Museum

As the birds adjusted to the space, the artist adjusted his instruments.

It took about three days to install the guitars, Smith says, and then Boursier-Mougenot “went through roughly a 10-day process of tweaking the sounds, thinking about which notes would come from where, which effects would come from where.”

Boursier-Mougenot calls the installation “a device—a plan. It’s a piece that’s impossible for humans to play.” Instead, the birds are his “flying fingers,” and after his departure the room takes on a life and a rhythm of its own.

Entering the space, your first instinct is to be silent, to stand still as you would while watching a wild animal in its natural habitat. But our interaction with the birds is part of the exhibit.

“The birds are also responding to our presence,” says Smith. “This is the nature of the work. The room is like a three-dimensional score, each of the guitars offers a certain sonic experience, and the birds choose where and how to interact with the room.”

Those choices shift when people walk around the guitars and beneath the aviaries. It’s obvious the birds respond to human presence, but how they react is surprising.  Rather than avoiding human visitors, these finches seek them out, showing great curiosity and desire to explore anything new that enters their space.

A finch on a shoe.
The finches are curious about the human visitors to their space.

Courtesy of Brian Barth

All that movement also creates more music. Smith says the birds think of the guitars as musical trees.

“Basically the room is their world now,” Smith said as he walked among the instruments. A female finch alighted on his shoe and he paused before gingerly taking another step. The finch stayed on board, tugging at the seams of his moccasins.

“This is the first time one has ever landed on me,” he whispered excitedly. “It’s pretty cool.”

Zebra finches are incredibly social and curious by nature, and they perform extremely well in Boursier-Mougenot’s orchestrated aviary.

“I am entirely fulfilled by my relationship with the Zebra Finches,” the artist said in an email when asked whether he was considering different birds for future exhibitions. “I don’t exclude the possibility of new partners, but as in all great love stories, it depends in part on the chance encounters life brings along.”

He found the birds currently in residence at the Peabody Essex through a casting company, Animal Actors Inc.

“They’re very social, they’re very musical, they have a very distinct appearance with that orange beak,” Smith says of the finches. “They’re almost like a companion species.”

Scientists have long used captive zebra finches to study birdsong, courtship, and brain circuitry. Heather Williams of Williams College in Williamstown, Mass., has worked with the birds for 25 years.

“Zebra finches are perfect for captivity,” she says. “They breed year round. The color green and high humidity trigger their breeding behavior, so in the presence of those elements they can breed continuously.”

There’s certainly a lot of breeding going on in the heat of the Barton Gallery.*

“We dispose of the eggs,” Smith explained. “The finches breed fairly rapidly, so we do what any breeder or pet owner would do that doesn’t want to be overrun by birds.”

What’s really striking is how bird courtship drives the ongoing performance of Boursier-Mougenot’s work. Rather than being deterred or inhibited by the sonic qualities of their environment, it seems as if the birds take ownership of the music as a means of interaction with one another.

“I think they’re perfectly capable of learning the consequences of hopping on one string versus another,” said Williams.

Birds of the same species often develop distinct regional dialects, demonstrating that their songs are not entirely innate but can be molded by what they hear around them. Williams agreed that the presence of actively resonating instruments could easily affect song development in younger males still in the early stages of song development.

“Birds that grow up in cities with a lot of traffic noise tend to develop songs that avoid the traffic noise,” she explained as a point of comparison. “During the learning process these birds develop a song that uses a clear channel.”

adult male and juvenile male.
Sonograms show the typical aspects of the zebra finch song.

Courtesy of Heather Williams/Williams College

In the wild, cutting through the mix can be essential not only for birds looking to attract mates but also for young birds trying to learn their parents’ songs. Williams went on to speculate that the finches could also demonstrate a preference for particular sounds in the exhibit and use them as a basis for imitation and new song composition, as well as adaptations in courtship behavior.

A male sings to a female in a separate cage to the left edge of the video frame. Video courtesy of Heather Williams.

The male birds do a courtship dance that’s coordinated with their song and involves pivoting from side to side and shifting as they move closer to the female. If they hop on certain strings, they could potentially coordinate the sound of the instruments with their overall courtship display.

“I have observed a lot of interesting behavior since January,” said Bradley Benedetti, a museum interpreter who spends hours a day at the exhibit. “I think the males are more interested in looking down at everything, to find a mate, and to keep watch on any competition. I call them scouts. The three guitars in the middle of the space, which only have a distortion effect on them, seem to be where the birds made a connection that they had something to do with the noise. After they made that connection, I noticed their relation to those guitars, and the bass guitars as well, changed.”

At its core, From Here to Ear is a piece of performance art. The environment is totally fabricated, the supply of food and water is constant, and the birds are bred in captivity. There’s even a veterinarian who tends regularly to the flock.

But that doesn’t mean the birds aren’t also behaving naturally. Even as professional animal actors, their resilience and adaptability around electrified instruments, blaring amps, and a stream of human visitors is remarkable. It reflects a successful adaptation that many bird species have made: tolerance to closer proximity with human settlements. It also gives us a chance to see their personalities as visitors to their world.

*Correction, April 10, 2014: This post originally misstated the name of the gallery in which the finches perform.

April 8 2014 11:30 AM

What's Wrong With Crappy Taxidermy?

The Internet loves awful taxidermy. The people behind the Tumblr Crappy Taxidermy, established as a blog in 2009 and featuring a deep archive of torturous photographs, have a book deal. An unrelated Facebook account, Crap Taxidermy, has 105,000 likes. The new kid on the block, @CrapTaxidermy on Twitter, already has 83,400 followers, despite having tweeted only 104 times.

April 3 2014 12:20 PM

How Can You Tell if a Reindeer Is Pregnant?

In a snowy valley on the island of Spitsbergen, 500 miles north of mainland Norway, a reindeer is getting a pregnancy test.

She's lying in the snow, grumpily. One leg has been popped out of the hobble that ties her other three legs together, and she has already used it to kick snow on me, the ultrasound machine, and veterinarian Erik Ropstad, who chuckles.


Spitsbergen is the largest island in the archipelago of Svalbard—no, it wasn't invented for the children's fantasy book The Golden Compass; it's a real place, with real polar bears. I spent a week there this time last year to report on a long-term study on reindeer for Smithsonian magazine.

Every spring since 1995, a few British and Norwegian scientists have been going to Svalbard to chase reindeer. They stay in a tiny cabin on the edge of vast, white Reindalen—Reindeer Valley. There's no running water but plenty of beer, box wine, and Scotch.

Each day they go out on snowmobiles to look for reindeer they've tagged in past years. They use binoculars to pick out an animal with collar and ear tags, usually high up on a hillside, send a snowmobile or two to herd it down to flat land, then chase it with a big net.

The idea is to understand how the numbers of reindeer change over the years—are there more? Fewer? What causes the ups and downs? They tag only females; if you want to understand how a group of animals is expanding and contracting, you really need to know about fertility.

Thus the pregnancy test.

Ropstad pulls the bottle of ultrasound gel out of his snowmobile suit where it has been staying warm against his body—reindeer don't like cold gel on their skin any more than humans do—and squeezes it on the probe, then holds the end of the probe to her nipple, the only piece of bare skin on a reindeer. Conveniently, it's right next to the uterus.

With bright white snow below, bright white mountains on either side, and bright white sky overhead, the screen looks like a solid piece of black glass. The solution to this problem is low-tech: an old blue sleeping bag to cover Ropstad's head and the screen so he can see the images. I join him under there.

There's a lot of stuff gurgling and swishing inside a reindeer's belly, so it takes an experienced eye to pick out a moving fetus among them. “The baby,” he says, pointing out its beating heart with one hand as he moves the probe with the other. I'll take his word for it—as far as I'm concerned, it could be a bit of rippling gut or an errant vole. "Pregnant, live!" he calls to the guy writing down the numbers on a data sheet.

The scientists' analysis suggests that what really harms Svalbard reindeer, in this changing world, is rain in winter. It dribbles through the snow and freezes on the ground like Magic Shell on a bowl of ice cream. Except it doesn't taste like chocolate and it can be inches thick, too much for the animals to paw through to get at the vegetation below. In bad years, animals go hungry and few are pregnant. It had been a good winter for the reindeer; not much rain fell. Nearly every female deer they caught that week was fat and pregnant.

This week the scientists are out chasing the reindeer again, for the 20th time, to find out how they made it through this year's warm, sometimes rainy winter. While North America was getting blasted by the polar vortex this winter, Northern Europe was freakishly warm. As the scientists chase down reindeer and look at their innards this week, they'll be finding out if fewer adorable baby reindeer will be joining the population this summer.

March 31 2014 12:25 PM

Japanese Whaling Finally Shut Down in the Antarctic

Japanese authorities have long defended the country’s controversial whaling program as necessary for scientific research. It’s the classic “we’re killing the animal to save the it” argument. But conservationists dispute that rationale, contending that the research program is merely commercial whaling in disguise. That’s hard to refute, since whale meat from the hunts is sold commercially in Japan and the program has produced no serious science.

The conservationists appear to have won today, as the International Court of Justice ruled in a 12-4 vote that Japan must halt its whaling program in the Antarctic. The decision, which specifically requires Japan to withdraw all permits for whaling in the Antarctic and not issue new ones, is considered to be legally binding. Japanese Foreign Affairs Ministry spokesman Noriyuki Shikata said that his country would abide by the ruling, but said it "regrets and is deeply disappointed by the decision."


The court found that there has been insufficient scientific output from the program, given that Japan has caught and killed around 3,600 minke whales since 2005 and produced just two peer-reviewed papers (which collectively refer to nine whales). The program also allowed a "lethal sample size" of 50 per species for fin whales and humpback whales, both of which are endangered.

Australia brought the case to the court in May 2010, accusing Japan of violating the International Convention for the Regulation of Whaling by producing whale meat for sale in Japan. Japanese authorities responded that the sale was intended to fund research, which is allowed under international law as long as the meat is a byproduct of research efforts. Japan agreed to a whaling moratorium in 1986 but has continued the practice under a clause that allows hunting some for scientific research.

The problem with that, according to Ken Collins, senior research fellow at the U.K.’s University of Southampton, is that killing the whales is totally unnecessary: "We do not need to kill whales to study them. Science has moved on a long way. We can learn much more by keeping them alive. There is a huge raft of techniques based on direct observation, photography and tracking available.”

The decision, while seen as a major victory among conservationists, will not mean the end of whaling. Japan also hunts whales—again, ostensibly for scientific purposes—in the northern Pacific, and Norway and Iceland do not abide by the 1986 moratorium. Moreover, the ICJ ruling did not specify whether whaling for research could be legal under better-designed studies. Nevertheless, the decision sets an important precedent by detangling the hunting of endangered animals and the conduct of scientific research.

March 27 2014 4:00 PM

Gorgeous Time-lapse Video of Fireflies

Photographer Vincent Brady’s most recent project uses an unusual light source: the mesmerizing glow of the firefly. His time-lapse photographs and videos are nothing short of stunning. The artist spent the summer of 2013 chasing the insects around Lake of the Ozarks in Missouri and his hometown of Grand Ledge, Mich. He exercised a diverse set of skills including long-exposure image stacking, meticulous editing, and steering a pontoon boat through narrow creeks on moonless nights.

The fireflies fill the frames with a frenzied movement that enables Brady to express a sense of transience against still ponds and starry skies. This romantic nod to non-permanence may recall a lost childhood pastime, but for the artist, the insects’ unpredictability sometimes created more practical challenges. The exact time and place of the firefly “disco,” he told me, often depended upon heat, humidity, and even the phase of the moon—they prefer to “throw down” in relative darkness, he says.


But it is in this erratic behavior that the artist most admires the insects. As he writes on his website, “Fireflies just bless you with their presence, light up, make love, and call it a life.” Brady captures the whole cycle in his frames.

March 26 2014 10:47 AM

Ocean Dandelions Are Some of the Weirdest Animals in the Sea

I was 12 when I first came across an ocean dandelion. I wish I had known then how strange these animals truly are. I was watching a documentary in which researchers had collected a deep-sea dandelion using a submersible, but upon returning to the surface, the dandelion had disintegrated into nothing but “petals.”

The announcer said: “We know almost nothing about the ocean dandelion. What it eats, how it reproduces, how it is put together.” Since watching this documentary, new species of ocean dandelions have been discovered, yet much of their biology remains poorly understood. But scientists do know something about how they are constructed, and when I found out 16 years later, I was in for quite a shock.

A few years ago I started work in a lab studying a strange group of animals called siphonophores that includes the Portuguese man-of-war. Turns out the ocean dandelion is a siphonophore, and these siphonophores challenge a simple assumption about what it means to be an animal.