What Spitting Cobras are Aiming For

iStock / Vadimborkin
iStock / Vadimborkin

Make most cobras angry, and they’ll bite you and inject the bite with a dose of venom. Frighten or tick off a spitting cobra, though, and it will contract the muscles around its venom glands and “spit” it out through holes in the tips of its fangs. Right into your face. 

Spitting cobras are no slouches when it comes to marksmanship. Neurobiologist Bruce Young found this out when he put on a plastic face mask a few years ago and taunted cobras into taking more than a hundred shots at him. When he analyzed the snakes’ movements, he found that they always spit right after he made a jerky movement with his head. The snakes would turn their heads in the same direction that he’d started to move his and then start spitting. Tracking the target like this, Young wrote in his study, “gives cobras a distinct geometric advantage; even relatively large linear movements on the part of the target can be accommodated by rather modest angular movements of the cobra's head.” A burst of speed when turning their heads also lets the snakes “lead” the target a little and compensate for the time it takes for their muscles to send the venom flying. 

It’s a cool tactic, but not as easy as just biting whatever it is that needs biting. You see, spitting cobra’s venom doesn’t do anything if it just hits you on the skin or even gets in your mouth. To be of any use, the venom has to get in your eye, where it causes searing pain and can scar the corneas and leave you blind.

This has had many biologists wondering if the cobras know to shoot for the eyes and are aiming at them. Given the snakes’ accuracy when spitting and the limited targets that their venom is effective on, scientists, zookeepers and others who study and work with spitting cobras assumed they were. In 2005, researchers from the University of Bonn in Germany backed these assumptions up with an experiment. They put undergrad student Katja Tzschätzsch face-to-face with 10 different cobras and got them to spit at her hands, her face and life-sized photos of faces. Hands and still faces and photos didn’t get a rise out of the snakes, but a moving face (real and fake) did—less so when the eyes were digitally removed from the photos than when they were left intact. When the researchers looked at the traces of venom on the photos and Tzschätzsch’s facemask, they found that the different cobras hit the eyes anywhere from 80 percent to 100 percent of the time.

Now a newer study suggests that maybe the cobras aren’t so picky when choosing their targets. Guido Westhoff, a neurobiologist who worked with Young and Tzschätzsch on the previous research, revisited the question last year with another round of experiments. He and his team presented cobras with life-size, human face-shaped boards with and without different kinds of glass eyes, as well as larger and smaller fake faces and triangular boards that didn’t resemble faces. 

In 324 spitting tests, the snakes didn’t spit at the boards with eyes any more than the ones without. Also, when the eyes on the targets were moved closer together or farther apart, the snakes didn’t adjust their aim to account for the distance between them. Given a choice between a face with eyes and an eyeless one, the snakes spit at the larger target most of the time, whether it had eyes or not. 

Westhoff now thinks that cobras don’t specifically aim for the eyes, but for the center of whatever body part their tormenter puts closest to them. Often, this just happens to be the face—and it seems the snakes prefer more face-like round targets than pointy ones; they spit at those almost four times as much—and at least one eye gets hit by chance. 

What’s more, he thinks that aiming for the eyes is both unnecessary and even a bad strategy for the snakes. Cobras can spray their venom over a wider area by moving their head as they spit and spitting several times in a row, increasing their chances of hitting the eye and without requiring them to aim right at them. Shooting for eyes instead of just a face also puts a cobra at a disadvantage if it can’t clearly see or recognize eyes, like when their own eyes become cloudy while they shed their skins, or in the dark. 

Could Gigantic Coconut Crabs Have Played a Part in Amelia Earhart’s Mysterious Disappearance? At Least One Scientist Thinks So

Getty Images
Getty Images

Amelia Earhart's disappearance during her attempt to fly around the world has captivated historians and conspiracy theorists for more than 80 years. One organization is now suggesting that her fate may have been sealed by giant crabs.

The International Group for Historic Aircraft Recovery (TIGHAR) believes that Amelia Earhart and navigator Fred Noonan may have landed their plane on Nikumaroro Island when they couldn't find their target, Howland Island, and that Nikumaroro's endemic crustaceans may have played a part in the ensuing mystery.

According to National Geographic, there are several clues supporting TIGHAR's theory. The large reef that hugs Nikumaroro’s coast makes it conducive to emergency aircraft landings. In 1940—just three years after Earhart’s disappearance—British colonists found 13 human bones beneath a ren tree on the island and shipped them to Fiji, where they were lost. The colony's administrator, Gerald Gallagher, sent a telegram back to England positing that it was Earhart’s skeleton. Then, in 2001, researchers uncovered U.S.-made artifacts around the ren tree including a jackknife, a woman’s compact, a zipper, and glass jars. The plot thickened even further in 2017, when four forensic bone-sniffing dogs all indicated that a human had indeed died at the site, though excavators failed to dig up any more evidence.

If those 13 bones beneath the ren tree did belong to the unfortunate castaway, where are the rest of her remains? Tom King, TIGHAR’s former chief archaeologist, thinks that coconut crabs can answer that question.

Nikumaroro is home to thousands of the colossal creatures, which can grow to a terrifying 3 feet across and weigh 9 pounds. They’re sometimes called robber crabs because of their penchant for absconding with objects that smell like food, and they’ll eat practically anything—coconuts, fruit, birds, rodents, other crabs, their own discarded body parts, and carrion.

It’s not unreasonable, then, to think that coconut crabs may have feasted on Earhart’s corpse and then taken her bones home with them. In one experiment to test the theory, TIGHAR researchers deposited a pig carcass on the island and filmed the aftermath. With the help of small strawberry hermit crabs, coconut crabs stripped the pig down to the bone in two weeks. After a year, some of the bones had been dragged 60 feet from the carcass’s original location, and some were never recovered at all.

King believes Earhart’s missing 193 bones could be hidden in the burrows of various coconut crabs. As in the pig experiment, crabs may have scattered some of Earhart’s bones dozens of feet away, but maybe not all of them—after all, the forensic dogs smelled bones near the ren tree that haven’t yet been located. Right now, TIGHAR is working with the Canine Forensics Foundation to further explore the area.

While we wait for more answers, dive into these other theories about Earhart’s disappearance.

[h/t National Geographic]

The Cat Sanctuary That Sits Near the Ancient Roman Site Where Julius Caesar Was Murdered

ClaireLucia/iStock via Getty Images Plus
ClaireLucia/iStock via Getty Images Plus

Cats will sleep anywhere—even in ancient ruins. Located in Rome, Colonia Felina di Torre Argentina is a cat sanctuary on the site where conspirators stabbed Julius Caesar 22 times outside the Theatre of Pompey, on March 15 44 BCE. Centuries later, in 1929, Mussolini excavated the area to reveal four temples that are 20 feet below the street level. Today, it’s the oldest open-air spot in Rome.

Bystanders can view the temple complex known as Largo di Torre Argentina from the fenced-off street, but according to Conde Nast Traveler, after a $1.1 million restoration process, the sanctuary will open to tourists in the second half of 2021. For now, the only living things allowed in the sacred area (area sacra) are feral cats.

According to Colonia’s website, they are "the most famous cat sanctuary in Italy” and also the oldest in Rome. Many of the cats fall into the special needs category: Some are disabled, missing part of a paw, or are blind; the special needs and elderly cats live in a walled-off area. Volunteers—a.k.a. gattare, or cat ladies—take good care of them, and some cats are available for adoption.

Atlas Obscura reports that “since the mid-1990s, the population has grown from about 90 to a peak of 250” cats and notes that the sanctuary has a spay/neuter program. From the street, visitors can watch gatti like the three-legged Pioppo and Lladrò—known as “poisonous kitten” because of how angry he was when he got there—sunbathe and sleep under pillars.

It’s unclear if the cats are respecting Caesar or disrespecting the fallen leader. However, a gift shop is open to visitors, and people can donate money toward the cats and/or volunteer.

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