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. 

Slow Motion Is the Only Way to Appreciate a Chameleon’s Lightning-Fast Tongue

From the unusual way they walk, to their ability to change color, the evolutionary adaptations of chameleons are pretty bizarre, and some of them remain mysterious even to scientists. Their super-powered tongues, for instance, can dart out so quickly that the movement can barely be seen with the naked eye. But modern high-speed cameras have enabled researchers at the University of South Dakota to observe this appendage at work like never before. The video below, shared over at The Kid Should See This, includes some of that groundbreaking footage, and it's pretty amazing to watch.

Shooting at 3000 frames per second, the camera was able to capture every split-second aspect of the chameleon's tongue strike. Slowed down, the video allows you to see how every component of the process works in harmony: First, muscles in the lizard’s tongue contract like the string of a bow. Then, when that tension is released, the bony base of the tongue shoots forward, pushing the sticky, elastic part toward the chameleon’s prey.

According to Christopher Anderson, one of the scientists who conducted the high-speed camera research, larger chameleons can catapult their tongues forward at distances of one to two times their body length. For smaller chameleons, this distance can reach up to two and a half times their body length. “Small chameleons need to be able to eat more food for their body size than large chameleons,” he tells bioGraphic in the video, “and so by being able to project their tongues proportionately further than these large species, they basically are opening up additional feeding opportunities to themselves that they wouldn’t have if they had a shorter tongue.”

To see one of nature’s greatest hunting tools in action, check out the full video below.

[h/t The Kid Should See This]

There May Be an Ancient Reason Why Your Dog Eats Poop

Dogs aren't known for their picky taste in food, but some pups go beyond the normal trash hunting and start rooting around in poop, whether it be their own or a friend's. Just why dogs exhibit this behavior is a scientific mystery. Only some dogs do it, and researchers aren't quite sure where the impulse comes from. But if your dog is a poop eater, it's nearly impossible to steer them away from their favorite feces.

A new study in the journal Veterinary Medicine and Science, spotted by The Washington Post, presents a new theory for what scientists call "canine conspecific coprophagy," or dogs eating dog poop.

In online surveys about domestic dogs' poop-eating habits completed by thousands of pet owners, the researchers found no link between eating poop and a dog's sex, house training, compulsive behavior, or the style of mothering they received as puppies. However, they did find one common link between the poop eaters. Most tended to eat only poop that was less than two days old. According to their data, 85 percent of poop-eaters only go for the fresh stuff.

That timeline is important because it tracks with the lifespan of parasites. And this led the researchers to the following hypothesis: that eating poop is a holdover behavior from domestic dogs' ancestors, who may have had a decent reason to tuck into their friends' poop.

Since their poop has a high chance of containing intestinal parasites, wolves poop far from their dens. But if a sick wolf doesn't quite make it out of the den in time, they might do their business too close to home. A healthier wolf might eat this poop, but the parasite eggs wouldn't have hatched within the first day or two of the feces being dropped. Thus, the healthy wolf would carry the risk of infection away from the den, depositing the eggs they had consumed away in their own, subsequent bowel movements at an appropriate distance before the eggs had the chance to hatch into larvae and transmit the parasite to the pack.

Domestic dogs may just be enacting this behavior instinctively—only for them, there isn't as much danger of them picking up a parasite at home. However, the theory isn't foolproof. The surveys also found that so-called "greedy eaters" were more likely to eat feces than dogs who aren't quite so intense about food. So yes, it could still be about a poop-loving palate.

But really, it's much more pleasant to think about the behavior as a parasite-protection measure than our best pals foraging for a delicious fecal snack. 

[h/t The Washington Post]


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