For Some Animals, Baby's First Meal is Its Mother

Franco Andreone, Wikimedia Commons // CC BY-SA 2.5

There are many animal moms that go above and beyond to give their children a leg (or wing or fin or tentacle) up in the world. A few mothers take that devotion to their family to a grisly extreme and allow themselves to become baby food.  

Among these are the caecilians, a group of wormlike, legless amphibians that live underground in the tropics. Some species give birth to live young, while others are hatched from eggs. In both groups, there are babies that come into the world with a set of blunt teeth built for scraping, which they put to use on their mothers. Scientists have found three different species where young caecilians get their first meal by stripping the skin off of their mothers’ backs with these specialized baby teeth. 

Shortly after they’re born, the little caecillians wriggle over mom and use their jaws to peel off a layer of fatty, nutrient-rich flesh. She doesn’t appear to mind, though. The scientists who discovered the flesh-eating behavior says the mothers stay pretty calm while they’re being flayed and don’t suffer any permanent harm—once the outer layer of skin is devoured, another takes its place. 

Other animal moms don’t have it so easy, and give a little bit more of themselves to their kids. Several spiders practice matriphagy and consume their mothers, which entomologist Mor Salomon—in wonderfully scientific deadpan—calls “an extreme form of maternal investment and an irreversible dead-end for the mother that precludes the possibility of future reproduction.”

One of these spiders is Stegodyphus lineatus, found in the Mediterranean and Middle East. Once a female’s 80 or so eggs hatch, she stops tending her web and eating, and devotes all her time to feeding her newborns. She pukes up a fluid made from what’s left of her last few meals and some of her own guts, which started breaking down while she guarded the eggs and built up as liquefied tissue in her abdomen. 

As the days go on and the spiderlings eat, mom’s innards continue to liquefy, and more of her guts and other organs like the ovaries dissolve as they become expendable. A little less than half of her body mass gets turned into food like this. 

After two weeks, mom has fed the children what she can and the well runs dry. The spiderlings then pierce her abdomen with their mouthparts and drain her of the rest of her body fluids. They’ll spend another two weeks at the nest with mom’s empty exoskeleton before going their own way. 

This kind of suicidal child care seems like a lot to ask, even of a devoted mother. Amazingly, though, there are some spiders that will serve themselves up as a meal even to kids that aren’t their own. A related species, Stegodyphus dumicola, is social and practices cooperative breeding. Females who don’t reproduce will help breeding spiders guard their eggs, feed their children through regurgitation and eventually allow themselves to be consumed. 

Big Questions
Why Do Cats 'Blep'?

As pet owners are well aware, cats are inscrutable creatures. They hiss at bare walls. They invite petting and then answer with scratching ingratitude. Their eyes are wandering globes of murky motivations.

Sometimes, you may catch your cat staring off into the abyss with his or her tongue lolling out of their mouth. This cartoonish expression, which is atypical of a cat’s normally regal air, has been identified as a “blep” by internet cat photo connoisseurs. An example:

Cunning as they are, cats probably don’t have the self-awareness to realize how charming this is. So why do cats really blep?

In a piece for Inverse, cat consultant Amy Shojai expressed the belief that a blep could be associated with the Flehmen response, which describes the act of a cat “smelling” their environment with their tongue. As a cat pants with his or her mouth open, pheromones are collected and passed along to the vomeronasal organ on the roof of their mouth. This typically happens when cats want to learn more about other cats or intriguing scents, like your dirty socks.

While the Flehmen response might precede a blep, it is not precisely a blep. That involves the cat’s mouth being closed while the tongue hangs out listlessly.

Ingrid Johnson, a certified cat behavior consultant through the International Association of Animal Behavior Consultants and the owner of Fundamentally Feline, tells Mental Floss that cat bleps may have several other plausible explanations. “It’s likely they don’t feel it or even realize they’re doing it,” she says. “One reason for that might be that they’re on medication that causes relaxation. Something for anxiety or stress or a muscle relaxer would do it.”

A photo of a cat sticking its tongue out

If the cat isn’t sedated and unfurling their tongue because they’re high, then it’s possible that an anatomic cause is behind a blep: Johnson says she’s seen several cats display their tongues after having teeth extracted for health reasons. “Canine teeth help keep the tongue in place, so this would be a more common behavior for cats missing teeth, particularly on the bottom.”

A blep might even be breed-specific. Persians, which have been bred to have flat faces, might dangle their tongues because they lack the real estate to store it. “I see it a lot with Persians because there’s just no room to tuck it back in,” Johnson says. A cat may also simply have a Gene Simmons-sized tongue that gets caught on their incisors during a grooming session, leading to repeated bleps.

Whatever the origin, bleps are generally no cause for concern unless they’re doing it on a regular basis. That could be sign of an oral problem with their gums or teeth, prompting an evaluation by a veterinarian. Otherwise, a blep can either be admired—or retracted with a gentle prod of the tongue (provided your cat puts up with that kind of nonsense). “They might put up with touching their tongue, or they may bite or swipe at you,” Johnson says. “It depends on the temperament of the cat.” Considering the possible wrath involved, it may be best to let them blep in peace.

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Why Crows Hold Noisy Funerals for Their Fallen Friends

The next time you hear a murder of crows cackling for no apparent reason, show a little respect: You may have stumbled onto a crow funeral. Crows are among the few animals that exhibit a social response to a dead member of their species. Though their caws may sound like heartbroken cries, such funerals aren't so much about mourning their fallen friends as they are about learning from their mistakes.

In the video below from the PBS series Deep Look, Kaeli Swift, a researcher at the University of Washington's Avian Conservation Lab, investigates this unusual phenomenon firsthand. She familiarized herself with a group of crows in a Seattle park by feeding them peanuts in the same spot for a few days. After the crows got used to her visits, she returned to the site holding a dead, taxidermied crow and wearing a mask and wig to hide her identity. The crows immediately started their ritual by gathering in the trees and crying in her direction. According to Swift, this behavior is a way for crows to observe whatever might have killed the dead bird and learn to avoid the same fate. Flocking into a large, noisy group provides them protection from the threat if it's still around.

She tested her theory by returning to the same spot the next week without her mask or the stuffed crow. She offered the crows peanuts just as she had done before, only this time the birds were skittish and hesitant to take them from her. The idea that crows remember and learn from their funerals was further supported when she returned wearing the mask and wig. Though she didn't have the dead bird with her this time, the crows were still able to recognize her and squawked at her presence. Even birds that weren't at the funeral learned from the other birds' reactions and joined in the ruckus.

Swift was lucky this group of crows wasn't particularly vengeful. Crows have been known to nurse and spread grudges, sometimes dive-bombing people that have harmed one of their own.

[h/t Deep Look]


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