© Sam Trull in Slothlove
© Sam Trull in Slothlove

RIP Monster, the Beloved Sloth Who Inspired a Scientist

© Sam Trull in Slothlove
© Sam Trull in Slothlove

A few months ago we introduced you to Sam Trull, a zoologist in Costa Rica who had taken on an incredibly difficult job: teaching orphaned baby sloths how to be wild. We delved into both sloth science and Trull's deeply committed, intimate care of these unique creatures that, from a scientific perspective, remain largely mysterious. We also created a Facebook-exclusive video featuring photos from Trull's excellent photography book, Slothlove, which documents her work with (and, clearly, love of) sloths. In short, we couldn't get enough of these sloths—and judging from the huge response to our coverage, neither could you.

Which is why we're now sharing some sad news: Monster, one of Trull's sloth stars, was recently attacked and killed by an ocelot.

Monster, a three-toed sloth, was just two weeks old when she came into Trull's care after having been rescued from the middle of a road. I met Monster—and Trull—in Costa Rica two years ago at Kids Saving the Rainforest, a rescue and rehab center for wildlife near Manuel Antonio, on the Pacific coast.

"Met" is the wrong term though; in her efforts to keep the sloths as wild as possible, Trull kept almost all the sloths out of sight and completely forbade any interaction between them and visitors (and most staff) of the wildlife rescue center. I lucked out during my visit, because Trull had taken Monster into a windowed lab with her while she tended to Tommy, a newborn baby howler monkey she wore strapped to her chest for hours on end. Our primate relatives need constant contact when they're young as much as our human newborns do, so Trull wore Tommy all day, every day.

In the video below, you can see baby Monster sitting in a basket serenely nibbling on hibiscus flowers while Trull feeds Tommy through a syringe. Trull is also a trained primatologist who spent years working with lemurs, so simultaneously tending to both Tommy and Monster—very different animals with very different needs—wasn't as strange as it may seem at first glance. It was impressive though.

Shortly after I shot this video, Trull and I sat down for a lengthy and fascinating interview. (She didn't wear Tommy to the interview; despite acting as his monkey mom, she was trying to keep him wild too, so my presence would have been problematic.) Her ambitious sloth rescue-rehab-release program—the main initiative of her newly launched nonprofit, The Sloth Institute Costa Rica—was in the late planning stages and hadn't really gotten off the ground yet. So there wasn't much to report on.

Yet for the next two years, her work stuck with me; it seemed like research that would push the envelope on both wild animal release and sloth science. People had attempted to release rescued sloths back into the wild before. It was largely a death sentence.

During that time, I checked in periodically with Trull to see how the project was progressing. She had created a sloth "boot camp": an enclosed, protected patch of forest where the animals could learn how to forage, among other essential skills, before being released back into the wild to fend for themselves. When I learned earlier this year that the first sloths to "complete" the boot camp were going to be released into the rainforest, I knew it was finally time to go full sloth for mental_floss readers.

The first sloths to be released were Kermit and Ellie. Monster, now 2.5 years old, followed suit soon after. Before Monster was released, Trull told me that she was both nervous and excited that her "slothy soulmate" would be living wild for the first time since she was just two weeks old. “Releasing her will be very emotional," she said. "But it’s also very amazing and reassuring to see their instincts kick in with certain things. At least they’re coming at this with some knowledge, and I don’t have to teach them everything. But to see them learn everything I’ve taught them is very rewarding as well.”

Monster survived for months on her own before the ocelot attacked her. Her death is a sad outcome, but it's also not especially surprising. Ocelots are a main predator of sloths, and sloths have few defenses. Their legendary slowness generally helps them avoid detection. But once spotted by a creature redder in tooth and claw than they are, there's little they can do to protect themselves.

So why are we telling you this story? Partially because I kind of fell in love with Monster when I saw her in that basket in Costa Rica two years ago. But primarily, because science is often portrayed inaccurately: as a flawless "last word" on a subject, a cold-hearted endeavor, or both. But science is neither absolute nor heartless. It's a method of investigating the natural phenomena of the world used by people who are, in my experience as a science journalist, largely driven by sincere curiosity and passion. It's a work in progress. It doesn't always go as planned. There's a lot of trial and error. Monster's death is a prime example of this basic truth: All the research, preparation, and good intent undertaken by a committed scientist couldn't save this one sloth from a predator who eats her kind. That's just the way it works in the rainforest.

But while Monster may be gone, what Trull learned about sloths by training, studying, releasing, and—yes—loving that three-toed, algae-covered, moth-hosting, hibiscus-eating, infrequently pooping animal will likely inform sloth science for years to come. And in a bit of good news, the other sloths Trull has released are doing well in the wild.

RIP, Monster.

If you'd like to support this science, The Sloth Institute of Costa Rica has created the Monster Memorial Fund; donations will support the construction of a Wild Sloth Health (WiSH) lab, where "research efforts will focus on monitoring different health parameters to get an overall picture of the quality of life of populations of sloths." They'll name the lab after Monster. You can also keep up with the Sloth Institute’s work through Trull’s Tumblr and Twitter feeds.

13 Facts About Opossums

Opossums, which include the roughly 100 species in the order Didelphimorphia, are some of the most misunderstood animals in the Americas. They’re often thought of as dimwitted, dirty creatures whose most impressive trick is acting like roadkill. The truth is just the opposite: Opossums are smarter, cleaner, and more beneficial to humans than many of their woodland neighbors. Read on for more opossum facts.


In North America, opossum and possum describe the same thing, but in Australia the word possum refers to a completely different animal. Among the most well known of their respective types are the Virginia opossum and the brushtail possum. Both are small to medium sized, omnivorous marsupials, but the similarities end there. The possum looks like a cute cross between a squirrel and a chinchilla and it belongs to a different order than the North American mammal that shares (most of) its name. Despite the potential for confusion, possum is accepted as the shortened version of opossum in this part of the world (and if you see the word possum in this list, you can assume it’s referring to the animal from the Americas).


Marsupials—mammals that carry and nurse their young in pouches—are absent from much of the world, and in Canada and the United States opossums are the sole representatives of the group. Like other marsupials, mother possums give birth to tiny, underdeveloped offspring (called joeys) that immediately crawl into a pouch where they live and nurse during their first months of life. Only once they’ve grown big and strong enough do they venture out, transitioning between their mother’s back and the warmth of the pouch until they mature into adults.


Possum playing dead.

Perhaps the most famous characteristic of the opossum is its tendency to play dead in front of predators. When the animal experiences intense fear in the face of danger, it seizes up and flops to the ground where it can remain for hours staring blankly ahead and sticking out its tongue. It’s an impressive defensive mechanism, but its effectiveness can’t be chalked up to the possum’s acting skills. Possums have no control over when they play dead or for how long they do it: The comatose-like state is an involuntary reaction triggered by stress.


A picture of a possum playing dead doesn’t really do it justice. To get the full experience, you need to be standing over to it to smell the putrid odor it emits when pretending to be a corpse. The smelly substance it secretes from its anus is just one more reason for foxes and bobcats to look for their dinner elsewhere.


Even if possums aren’t the cutest creatures in the forest, they should be a welcome addition to your backyard. Unlike other mammals that carry ticks, and therefore spread Lyme Disease, possums gobble up 90 percent of the ticks that attach to them. According to the National Wildlife Federation, a single possum consumes 5000 of the parasites per tick season. That means the more possums that are in your area, the fewer ticks you’ll encounter.


Possum looking up at table.

Opossums have impressive memories—at least when it comes to food. Researchers found that possums are better at remembering which runway led to a tasty treat than rats, cats, dogs, and pigs. They can also recall the smell of toxic substances up to a year after trying them.


While most animals look at a snake and see danger, a possum sees its next meal. The animals are immune to the venom of nearly every type of snake found in their native range, the one exception being the coral snake. Possums take advantage of this adaptation by chowing down on snakes on a regular basis.

Researchers have been trying to harvest possums’ antivenom powers for decades. A few years ago, a team of scientists made progress on this front when they recreated a peptide found in possums and and found that mice given the peptide and rattlesnake venom were successfully protected from the venom’s harmful effects.


While possums aren’t totally immune to rabies (a few cases have been documented), finding a specimen with the disease is extremely unlikely. Marsupials like possums have a lower body temperature than the placental mammals that dominate North America—in other words, their bodies don’t provide a suitable environment for the virus.


Baby opossum hanging from a tree branch by its tail.

Opossums are one of a handful of animals with prehensile tails. These appendages are sometimes used as an extra arm: They can carry grass and leaves for building nests or grip the sides of trees to provide extra stability while climbing. Baby possums can even use their tails to hang from branches upside down as they’re often depicted doing in cartoons. But it’s a myth that possums sleep this way: Their tails are only strong enough to hold them for a short amount of time.


Thanks to their whole acting-and-smelling-like-a-corpse routine, opossums aren’t known as the most sanitary animals in nature. But they take cleanliness seriously: The Washington Department of Fish and Wildlife writes that possums, like housecats, use their tongue and paws to groom themselves frequently and thoroughly. Possums largely lack sweat glands, and this behavior is believed to help them cool down. It also has the added effect of rendering them odorless (when they’re not secreting stinky predator-repellant, that is).


Close-up on opossum's face.

One of the opossum’s most recognizable features is its pair of opaque eyes. Opossum eyes do have whites and irises, but because their pupils are so large, their eyes appear completely black from a distance. The exaggerated pupil dilation is thought to help the nocturnal animals see after the sun goes down.


It was long assumed that opossums like to keep to themselves, but a study published in the journal Biology Letters suggests they have a social side. Researchers at the Federal University of Pernambuco in Recife, Brazil observed some possums in captivity sharing dens even if they weren’t mates. In one case, 13 white-eared opossums of various age groups were cohabiting the same space. The scientists suspect that male and female possums living in the wild may even build nests together as a way to trigger the female’s reproductive hormones.


The way it gives birth and raises its young isn’t the only thing that’s interesting about the opossum's reproductive life. Females have two vaginal tracts and two uteri, and males in turn have a forked or bifurcated penis. This is fairly typical for marsupials, but when European colonizers first landed in North America centuries ago, they didn’t know what to make of the confusing genitalia. One explanation they came up with was that male opossums impregnated females through the nose.

Hero Crayfish Cheats Death By Removing Its Own Claw to Escape Pot of Boiling Water

There remains a perpetual debate over the ethical consequences of taking a crustacean and boiling it alive. In early 2018, Switzerland actually made it illegal to give living lobsters a scalding hot bath. (Instead, chefs are expected to stun them electronically before submersion.) Scientists can’t reach a conclusion over whether decapods feel pain—or if we can even define what that means for them.

While humans argue, some clawed sacrifices are taking action. A crayfish filmed by a Facebook user in China is making the internet rounds and being hailed as a hero after taking dramatic measures to escape a boiling pot of water.

In the footage, the crayfish appears to be unable to extricate its left appendage from a bubbling vat of doom. Rather than succumb, the crayfish uses its right claw to sever its compromised claw and scurry off. At 11 seconds, it’s the best summary of a Saw film possible.

“Juike,” the user who originally posted the video to the Weibo social media site, says he has taken the crafty invertebrate home and put him in an aquarium as a pet. The tiny survivalist may even regrow his lost limb, as crawfish are able to do, although it might not reach its former size.

Crayfish are in inherent danger of being turned into soup in China, where specialty restaurants devoted to their preparation are popping up. Some observers believe their popularity is due to diners having to step away from phones and social media in order to use both hands to peel away at their shells.

[h/t BBC]


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