What Do Animals Think They See When They Look in the Mirror?
The six horses in a 2002 study were “known weavers.” When stabled alone, they swayed their heads, necks, forequarters, and sometimes their whole bodies from side to side. The behavior is thought to stem from the social frustration brought on by isolation. It can be seen in a small percentage of all stabled horses, and owners hate it—they think it causes fatigue, weight loss, and uneven muscle development, and it looks disturbing.
People had tried stopping the weaving by installing metal bars that limit a horse’s movement, but the study found that a different modification to the stable worked surprisingly well: a mirror. “Those horses with the mirror were rarely [observed] weaving,” the researchers reported. A later study even found that the mirror worked just as well as the presence of another horse.
Studies have shown that mirrors can improve the lives of a variety of laboratory, zoo, farm, and companion animals. Isolated cows and sheep have lower stress reactions when mirrors are around. With mirrors, monkeys alone or in groups show a healthy increase in social behaviors such as threats, grimaces, lip-smacking, and teeth chattering, and laboratory rabbits housed alone are also more active. Mirrors in birdcages reduce some birds’ fear.
But why? Other animals have a very different experience with mirrors than people do. According to the prevailing science, individuals of most species can’t recognize their reflections as themselves. The only known exceptions are humans, some great apes, and possibly dolphins, elephants, and magpies—all animals with high intelligence.
Gordon Gallup invented the test that shows whether an animal recognizes itself in the mirror: He marked primates’ faces and ears with dye and watched whether they used a mirror to investigate the spots. If they did, it revealed that the animals understood that the faces in the mirror were their own. But he thinks that most animals probably think of their reflections as another animal. The calming effect in some cases could come partly from the reflection’s apparent mimicking. “The animal confronting its own reflection in a mirror has complete control over the behavior of the image, and therefore the image is always attentive and ready to reciprocate when the animal is,” he and Stuart Capper wrote in 1970. In other words, the mirror image is sort of like a friend who always does exactly what you want.
Yet it does seem likely that some animals are intelligent enough to notice that there are differences between a reflection and a real animal—an animal in a mirror has no smell or sound, and for that matter, no body. Even fish may get that: Researchers have routinely used mirrors to test aggression levels in fish because fish are among the creatures that react fearfully to their mirror images. But a study published in May found that two out of three related cichlid species exhibited differing responses to a mirror image and to an actual live opponent. Another study found differences in brain gene expression levels depending on whether fish were meeting other fish or a mirror. “Clearly, the fish recognize something unusual about the mirror image and the differential brain response may reflect a cognitive distinction,” the authors write.
Whatever animals do conclude about the creature in the mirror, mirrors sometimes lead to bizarre (and unhelpful) behaviors. Many bird owners have horror stories of their male birds “mating” with their reflections and continuously masturbating. This mirror-image mate can also stimulate females to lay eggs, which can be dangerous for them because it depletes calcium, causing brittle bones and other health problems. Pair-bonding birds, like budgies, may bond with their mirror image and snub their owner. Mice feed less around mirrors, suggesting that mirrors may not be ideal companions for rodents, either.
When it comes to dogs and cats, reactions vary. The first mirror exposure can be hilarious, with the young animal trying to play or fight with its reflection—and ending up completely confused. Eventually most of them ignore or even avoid their reflections, although some dogs continue to growl when confronted with a mirror. But it’s clear that some pets, especially cats, continue to be entertained by their reflections, preening and performing acrobatics in front of the mirror, making it seem for all the world like they recognize themselves.
Though mirrors may provide comfort and entertainment, they are clearly not enough for most social animals. The most poignant example is a study of young monkeys raised with only mirrors for companionship. Not surprisingly, the monkeys displayed a sad mix of “autoeroticism, self-clasping, stereotypy, and bizarre posturing,” behaviors known as isolation syndrome. The same would be true for isolated cats, dogs, birds, and other pets. If you’ve got one, you know: They accept no substitute for the person you see in the mirror.
Orcas, Via Drone, for the First Time Ever
Drones are so hot right now. From peeking inside the mouth of an active volcano to recreating Tatooine pod races, unmanned aerial vehicles are in, and their utility (thankfully) extends far beyond the battlefield. For proof of this, look no further than the Vancouver Aquarium’s use of a custom-built hexacopter to track and monitor its local orca population, shown in the video above.
The first-of-its-kind study—which was a team effort of the aquarium’s Lance Barrett-Lennard and National Oceanic and Atmospheric Administration researchers Holly Fearnbach, John Durban, and Wayne Perryman—was put together to determine the impact of salmon fisheries on the resident orca population. Research showing a correlation between poor salmon years and spikes in orca deaths indicated that the connection was strong, but there was no way to know for sure until the team had a clearer idea of the whales’ exact feeding habits and preferred salmon-hunting locales.
Additionally, orca deaths were too black-and-white a measuring stick to create long-term strategies for reviving the dwindling whale population. As Barrett-Lennard says in his post about the study, “John [Durban] and I felt that a more sensitive measure of food stress—thinness rather than starvation—was needed, so that the role of prey availability could be better understood and salmon fisheries could be managed with the needs of killer whales in mind.”
Taking all of this into account, the team put their heads together with Don Leroi of Aerial Imaging Solutions—who had already been developing a UAV for NOAA at the time—and out came Mobly, their “steady, stable, and quiet” hexacopter. With the drone in tow, Barrett-Lenard and Co. took to the water, where they were able to capture two weeks of unbelievable footage of orcas in their natural—and undisturbed, thanks to Mobly—habitat.
The result? Using a formula developed by Durban for determining whale length and dorsal fin height, they were able to confirm that the orcas in the area were generally “robust” (unsurprisingly—it'd been a good season for Chinook salmon). Perhaps more importantly, Mobly proved its worth as a research tool. As Barrett-Lenard said: “We are convinced now that Mobly—or one of his cousins—will be an invaluable part of our research program for years to come, as we focus on recovering resident killer whale populations by, among other things, ensuring they have enough to eat.”
Well done, Mobly. Head on over to the Aquarium’s blog for a more in-depth look at the study.
Gertjie and Lammie, a Magical (and Bizarre) Friendship
Gertjie is a rhino. He looks like a rhino, he (probably) smells like a rhino, and if rhinos could talk, he would presumably talk like a rhino, too. He does not, however, always act like a rhino. As you’ll see in the video above, Little G—as his handlers at the Hoedspruit Endangered Species Centre in Pretoria, South Africa, affectionately call him—is attached at the hip to a young lamb, who, apparently, causes the rhino to momentarily forget what species he is.
Orphaned last May when his mother was killed by poachers, Gertjie arrived at HESC with a rhino-sized hole in his heart. Enter Lammie, the affable lamb who would fill that hole, and in the process build a bond strong enough to cause Little G to prance around the reserve as if he too were a small, agile lamb—And not, you know, one of the more intimidating herbivores on the planet.
Filmed by Assistant Curator Karien Smit in order to catch the “very special pair” in action, the visual of Little G hopping around on all fours should be both a ridiculous and hilarious sight. But, to be honest, it’s suddenly so gosh darn dusty in here that it’s hard for me to focus on anything other than the fact that an orphaned rhino and lamb are BFFs.
Marriage Equality’s New Mascot: A Hermaphroditic Snail
In what may be the oddest honor of the year, scientists in Taiwan have named a newly discovered hermaphroditic land snail in honor of same-sex marriage.
The snails, named Aegista diversifamilia, native to eastern Taiwan, were long thought to be members of another species, named A. subchinesis. But in 2003, researchers noticed physical differences between the snails east and west of Taiwan’s Central Mountain Range: Those east of the mountain range have bigger, flatter shells than their more conformist A. subchinesis counterparts to the west.
Following up on this observation, Ph.D. candidate Chih-Wei Huang at National Taiwan Normal University studied the snails’ molecular markers and morphology, and the verdict was in: It’s a new species.
The researchers published the study Monday in the open-access journal ZooKeys. Taiwan and many other parts of the world have been struggling for equality in marriage rights. This inspired the researchers, while they were preparing their manuscript, to pick the snail’s name. Aegista diversifamilia translates to “the diverse forms of human families.” It is particularly fitting because the snails are hermaphroditic animals, meaning they all have both male and female reproductive organs.
“They represent the diversity of sex orientation in the animal kingdom,” said Yen-Chen Lee of Academia Sinica in Taipei in the research press release. “We decided that maybe this is a good occasion to name the snail to remember the struggle for the recognition of same-sex marriage rights,” said Lee, who was one of the first to notice the snails’ physical distinction.
The newly dubbed, albeit sluggish, mascot could be seen as an oddly apt, optimistic representation for the same-sex marriage struggle: Slow and steady wins the race.
The Hardest Thing About Being a Cheetah
Why are wild cheetah populations declining so precipitously? In 1900, Africa was home to around 100,000 of the dappled predators; in 2014, that number has shrunk to 10,000. Conventional wisdom holds that cheetahs, like wild dogs, are prime victims of kleptoparasitism, or prey theft by larger predators. The slender cats, which usually weigh between 110 and 140 pounds, are great at catching antelopes, but not so good at fending off bigger beasts, like lions and hyenas.
This narrative has gained traction in conservationist circles: Pity the graceful under-cat of the grasslands, working hard to catch prey that is then stolen from its claws. (By the way, cheetah claws are a specialized marvel. Because the felines run so swiftly—accelerating, at times, from zero to 60 mph in just three seconds—their hare or gazelle dinner might try to thwart them in the chase by zigzagging. But cheetahs use distinctive, protruding nails to give them traction during lightning-fast turns.) The idea of the bullying lion or opportunistic hyena fits into our somewhat anthropomorphized vision of the animal kingdom—and, sure, other mammals do poach off these cats’ labor occasionally. But a new paper in Science suggests that the real culprit in the decline of the cheetah isn’t some jungle despot exacting his meaty tribute. It’s us.
The researchers wanted to directly test the claim that kleptoparasitism was pushing cheetahs “over an energy precipice”—that, after exhausting all their resources running down lunch, the cats were deprived of the means to replenish the store after their food was stolen. To do this, the scientists had to figure out how much energy cheetahs actually spent chasing their food. Feline test subjects were captured from two South African wildlife reserves, injected with water labeled with distinctive isotopes, released, and tracked. The ratio of isotopes in the cheetahs’ waste revealed how much oxygen they were using for a given activity—how hard they were breathing, and thus, how strenuously they were working.
After collecting and analyzing the waste, the researchers reached a surprising conclusion. Unlike wild dogs, which often pursue a target with dogged determination over long distances, cheetahs don’t actually blow a lot of their daily energy tailing prey. (A typical chase only lasts a few seconds.) What saps their strength is walking. The cats under observation walked miles and miles searching for quarry they could hunt—miles that were necessary only because human development has so depleted their meal options. The fences we’ve built separate them from impalas, hares, and antelopes. The habitat we’ve razed was once a predator supermarket.
In short: Cheetahs would be fine with lions and hyenas occasionally mooching their food if humans weren’t forcing them to walk themselves to death.
As John Wilson, one of the study authors and a biologist at North Carolina State University, put it bluntly, “Cheetahs aren’t weak. It’s us making them weak.”
We can’t deflect responsibility for our ecological impact onto a bunch of (surprisingly well-mannered!) lions and hyenas.
Some Sharks Are Socialites, Some Want You to Go Away
“I am a nice shark, not a mindless eating machine,” intones Bruce the Shark in 2003’s hit kids’ movie Finding Nemo. He is trying so hard. Unfortunately for him, according to his creators, to be a shark does pretty much consist of mindlessly, mechanistically eating things. Struggling to transcend biological destiny, poor one-dimensional Bruce is played for laughs.
It was cruel, and wrong. A study last week in Behavioral Ecology and Sociobiology suggests that not all sharks (#notallsharks) are alike. The paper, “Shark Personalities? Repeatability of social network traits in a widely distributed predatory fish,” finds that these terrors of the deep may vary by social temperament.
Specifically, researchers discovered that some individual sharks are convivial and some are emo. Some prefer to band together into gangs, while others camouflage quietly into the background. The scientists observed 10 different groups of juvenile small spotted catsharks in large tanks that contained three different habitats. The habitats differed in their structural complexity, from a few rocks and plants to dense underwater foliage. The researchers’ aim was to observe how the teenage sharks—who, like most human high school students, are prone to feel vulnerable—interacted in environments with various amounts of cover.
And? In the words of behavioral ecologist David Jacoby, “socially well-connected [shark] individuals remain well-connected under each new habitat.” (Being well-connected when you are a catshark is a literal as well as figurative condition: It means you tend to lie on top of other catsharks, i.e. spoon.) Likewise, weirdo loner sharks isolated themselves no matter where they were, even shading their skin color to blend in better with the gravel substrate at the base of the tank. (If only I could have done that at my school dances.)
“We define personality as a repeatable behavior across time and contexts,” said Darren Croft, a professor at the Center for Research into Animal Behavior at the University of Exeter. Many animal species exhibit what scientists think of as personality traits, but Croft and his team are the first to seek out such qualities in sharks—creatures popularly viewed as uniform in their terrifying appetites, the most coolly insatiable of our underwater villains.
Of course, both the gregarious catsharks and the shy ones probably like eating fish. The second kind are just more likely to go home afterward and curl up with an old movie.
Why I Gave Mouth-to-Mouth Resuscitation to a Turtle
As my lips slowly moved toward the mouth of the turtle in my lap, I admit to momentarily wondering how my life’s choices had brought me to this point.
As a research fellow with the Alabama Natural Heritage Program at Auburn University, one of my responsibilities is to help out on surveys and monitoring efforts so we can figure out how populations of rare species are doing in the state. One of Alabama’s most iconic species is the Alabama red-bellied turtle (Pseudemys alabamensis); this species is the official state reptile, but it is also listed as endangered by the U.S. Fish and Wildlife Service. The turtle has a very restricted geographic range—only a few rivers leading into Mobile Bay in Alabama and two nearby rivers in Mississippi—and that is the main reason why biologists think it is so vulnerable to extinction. But there have been remarkably few studies that actually attempted to estimate how many turtles are left.
A few weeks ago I was in Mobile Bay, assisting Jim Godwin, the Heritage Program’s aquatic zoologist, on a turtle survey. Our sampling protocol was to set a number of mesh traps—usually referred to as hoop traps because they are held open by a series of hula hoop-type structures—in the water and then come back and check them every day for a few days. Turtles swimming around in the water will encounter the nets and be funneled into an area that is difficult for them to escape from.
Now, what you may not know is that this coastal area of southern Alabama is a very important place for reptiles and herpetologists alike: There are more kinds of native turtles here than just about anywhere else in the world, with the possible exception of a couple of spots in Southeast Asia. So we may be targeting Alabama red-bellied turtles, but our traps are not selective, and it is not unusual to get some really cool bycatch, such as alligator snapping turtles and softshell turtles, not to mention things like the occasional ornery alligator.
Trapping turtles in this area can be unpredictable for a few other reasons, too. Because these rivers are so close to the ocean, they are subject to tides, and sometimes water levels fluctuate more than we expect. This sometimes causes the water to rise above the trap’s air pockets we leave inside for the turtles to breathe, pockets that are usually held open by a floating plastic container. In these rare cases, a drowned turtle is a very real possibility.
As we motored to a trap one morning, we were dismayed to see that the entire trap was underwater. And, as we feared, there was a large and completely limp turtle on the bottom of the trap. The animal wasn’t an Alabama red-bellied turtle; it was a closely related adult female Florida cooter. Although the two species look similar, the Florida cooter is common and widespread throughout the Southeast. That didn’t make the sight of this drowned turtle any less frustrating, though.
It’s hard being a young turtle—the silver-dollar-size animals are scarfed down by just about everything with a mouth. However, once a turtle reaches maturity, there aren’t many predators that can mess with it. This allows the population to compensate for the high juvenile mortality because adults can survive and produce a lot of young over many years. That is, as long as a couple of biologists don’t accidentally drown them.
I placed the lifeless turtle on the bottom of the boat and figured that we could at least donate it as a specimen to the Auburn Museum of Natural History; the collections there are useful for research and teaching. Then I turned my attention to helping measure and mark the other cooters we captured. (Fortunately, the rest of the turtles in that trap were all alive and doing well.)
After some time, my eye caught a slight movement from one of the turtle’s limbs. I knew that turtles were incredibly resilient animals and I had even heard of researchers resuscitating turtles that had spent too long in submerged traps. Thinking back to a first aid class I had taken a few years earlier (and egged on by my partner, Olivia, who was tagging along on the trip), I decided to try CPR. The first thing I did was hold the turtle upside down to let any liquid escape, then I placed the turtle on my lap, held its jaws open, and blew into its open mouth.
I’ve been bitten by a lot of turtles in my life, and it hurts. A lot. Because I was afraid of a suddenly alert turtle chomping down on my tongue, I tried to maintain a slight distance between our mouths. I was hoping that this would also reduce my chances of smelling any of the turtle’s last meal … or contracting salmonella.
Although I could hear that air was entering the turtle, there was no reaction. I tried blowing more air. Nothing. Then I remembered that chest compressions might help with blood circulation and might even expel air and any remaining water from the lungs.
Pushing down on the turtle’s chest was not an option—the animal’s shell prohibited it. So I reached back under the shell and attempted to push the skin forward. I heard air coming out of the turtle’s mouth and was even more encouraged when, after a momentary and tense pause, the turtle took a deep breath of its own.
Almost immediately, the turtle became more active and starting flailing around with its limbs. Perhaps more entertaining is that at this point air started coming out of other orifices too (something you can hear on the video).
Although things were looking up for this Florida cooter, we decided she was still too weak to be immediately released, so we held onto her for another hour or two while we checked the rest of the traps, always making sure she was staying cool by keeping a wet cloth on her. At the end of the day, we motored back to the site where we had first captured her, placed her in the water, and took a sigh of relief as she propelled herself into the murky darkness of the river.
A Parrot Passes the Marshmallow Test
Can your kid pass the “marshmallow test”? And what does it mean if he can’t, but a parrot can?
The marshmallow test is pretty simple: Give a child a treat, such as a marshmallow, and promise that if he doesn’t eat it right away, he’ll soon be rewarded with a second one. The experiment was devised by Stanford psychologist Walter Mischel in the late 1960s as a measure of self-control. When he later checked back in with kids he had tested as preschoolers, those who had been able to wait for the second treat appeared to be doing better in life. They tended to have fewer behavioral or drug-abuse problems, for example, than those who had given in to temptation.
Most attempts to perform this experiment on animals haven’t worked out so well. Many animals haven’t been willing to wait at all. Dogs, primates, and some birds have done a bit better, managing to wait at least a couple of minutes before eating the first treat. The best any animal has managed has been 10 minutes—a record set earlier this year by a couple of crows.
The African grey parrot is a species known for its intelligence. Animal psychologist Irene Pepperberg, now at Harvard, spent 30 years studying one of these parrots, Alex, and showed that the bird had an extraordinary vocabulary and capacity for learning. Alex even learned to add numerals before his death in 2007. Could an African grey pass the marshmallow test?
Adrienne E. Koepke of Hunter College and Suzanne L. Gray of Harvard University tried the experiment on Pepperberg’s current star African grey, a 19-year-old named Griffin. In their test, a researcher took two treats, one of which Griffin liked slightly better, and put them into cups. Then she placed the cup with the less preferred food in front of Griffin and told him, “wait.” She took the other cup and either stood a few feet away or left the room. After a random amount of time, from 10 seconds to 15 minutes, she would return. If the food was still in the cup, Griffin got the nut he was waiting for. Koepke and colleagues presented their findings last month at the Animal Behavior Society meeting at Princeton.
At every time period tested, Griffin successfully waited at least 80 percent of the time, even at the maximum 15 minutes. That’s the best performance ever seen in an animal, comparable to Mischel’s original results with preschoolers.
Human children faced with the test use a variety of strategies to distract themselves from the tempting first marshmallow. Similarly, the bird didn’t always just sit in peaceful anticipation of receiving his treat. Sometimes he tossed the lesser food away or gave it a taste, or he distracted himself with preening. (Koepke and colleagues produced this video directly comparing Griffin to children put through the test.)
What does it mean? Well, we already know that Griffin is a pretty smart bird. He has a large vocabulary, knows the names of dozens of objects, and can recognize colors, shapes, and numbers. Pepperberg has compared his intelligence that of a five- or six-year-old child. Perhaps it shouldn’t be all that surprising that he could master the marshmallow test.
However, Gray noted, “I don’t believe Griffin was unique.” Members of other bird species would probably be able to accomplish the same thing, given the right circumstances, she said.
Goffin’s cockatoos were put to the test by researchers at the University of Vienna last year and could manage only a bit over a minute at best. But these birds had to hold the reward in their beaks, rather than look at it on the table. “It’s a little unfair,” Koepke said. How many of us would be able to resist eating something tasty if it were put in our mouths? If these birds were tested in the setup used for Griffin, they, too, may have succeeded.
But the marshmallow test isn’t necessarily one about smarts. A couple of years ago, researchers discovered that trust was a key factor. When the experiment was altered so that kids had no reason to trust the experimenter telling them to wait, they often didn’t bother. Griffin, Gray noted, lives in a trustworthy environment—he has no reason to doubt that the promise of a treat will be fulfilled.
But wouldn’t it be interesting to watch what would happen, Gray speculated, if he were confronted with an experimenter he didn’t trust? Perhaps he’d be just as unwilling to wait as anyone else.
Marmosets Can Learn New Tricks—by Watching a Video
Finally, irrefutable evidence that not all TV is bad for your brain. In an attempt to determine whether monkeys can acquire new skills and behaviors from outside of their immediate social group, biologists used a video tutorial to train wild marmosets to open a box. The team, led by Tina Gunhold from the University of Vienna, first recorded already-trained marmosets opening the box (which contained a treat), then outfitted a tree with the box and video, and finally showed the recording to marmosets in the wild.
The video above shows the savvy marmosets in action. All phases of the experiment are on display—from the monkeys watching the video, to the implementation of what they've learned, to their gleeful retreat after they've secured their prize. In addition to being downright cute, it serves as an exceedingly fascinating display of animal ingenuity.
The results of the study were published in Biology Letters, with the authors stating that not only was the experiment mostly a success (only 12 of the 108 marmosets opened the box, but of those, 11 had watched the video), it was also, to their knowledge, "the first study that used video demonstrations in the wild and demonstrated the potent force of social learning, even from unfamiliar conspecifics, under field conditions."
What Happens When You Raise Walking Fish Entirely on Land?
Native to freshwater African riverbanks, bichirs are famous for their strong fins and lungs, allowing them to “walk” and breathe out of water. But the serpentine fish prefer aquatic habitats, and tend only to travel on land when they must.
For a new study published in Nature, researchers from the University of Ottawa and McGill University decided to find out what would happen if they raised bichirs entirely in terrestrial environments for eight months. They hoped to learn more about the transition of sea animals to land some 400 million years ago, an evolutionary turning point that bichirs may be uniquely poised to help us understand.
The team was surprised to find that the fish not only survived, but seemed to adapt and thrive in their new homes. As explored in the Nature-produced video above, the land-dwelling bichirs provided an exciting snapshot of a crucial moment in the evolutionary record.