Why Do Cats Eat Grass? Scientists Might Have Figured It Out

AllaSaa/iStock via Getty Images
AllaSaa/iStock via Getty Images

Dogs are nature’s garbage disposals. They eat anything from table food to foreign objects to poop. Cats are more discriminating, though both of these domesticated animals seem to enjoy munching on grass. We have a pretty good idea why dogs do this—it’s often to relieve stomach discomfort and induce vomiting—but why cats like to nibble on lawns has largely remained a mystery. Now, scientists believe they have an answer.

A presentation last week at the International Society for Applied Ethology annual meeting in Bergen, Norway offered evidence on this peculiar behavior, which many cat owners attribute to the animals' urge to fix an upset stomach. Researchers at the University of California, Davis conducted a survey of 1021 cat owners who spent at least three hours a day observing their pet’s activities and found that of the 71 percent of cats caught chomping on grass, about a quarter wound up vomiting afterward—but roughly 91 percent of respondents reported that their cats did not appear to be ill before dining out on roughage.

So if they weren’t self-medicating a sick stomach, what happened? The scientists argue it’s evolutionary behavior that is not intended to provoke vomiting. Instead, cats are motivated to eat grass because this is how their ancestors expelled intestinal parasites. Grass consumption increases muscle activity in the digestive tract, which could force out unwanted contents. Cats have traditionally had to deal with parasites like hookworms or roundworms as a byproduct of devouring rodents, though it’s likely that most cats who aren’t on a diet of rat meat don’t have any parasites to treat. Still, the instinct to chew grass remains.

The survey also indicated cats younger than 3 years old were more likely to eat grass than older cats, but tend to vomit less afterward. If you have an outdoor cat who likes to supplement its diet with backyard salads, it might be best to offer up some grass grown indoors that is free of pesticides and other contaminants.

[h/t Science]

Meet LiLou: The World's First Airport Therapy Pig

Kseniia Derzhavina/iStock via Getty Images
Kseniia Derzhavina/iStock via Getty Images

There's a new reason to get to the airport early—you might run into a therapy pig who's there to make your trip a little easier. As Reuters reports, LiLou the Juliana pig is a member of San Francisco International Airport's "Wag Brigade," a therapy animal program designed to ease stress and anxiety in travelers.

Aside from her snout and potbelly, LiLou can be recognized by her captain's hat and red "hoof" polish. She spends the day with guests who are happy to take a break from the pressures of traveling. She might comfort them by posing for a selfie, playing a song on her toy keyboard, or offering them a head to pet.

After bringing joy to people's day, LiLou goes home to her San Francisco apartment where she lives with her owner, Tatyana Danilova. In her free time, she goes on daily walks and snacks on organic vegetables. She even has her own Instagram account.

Airports around the world are embracing the benefits therapy animals can bring to customers. The Wag Brigade program at San Francisco includes a number of dogs, and earlier this year, the Aberdeen Airport in Scotland debuted its own "canine crew" of dogs trained to make travelers feel safe and happy. Therapy miniature horses have even been used at an airport in Kentucky. According to the San Francisco Airport, LiLiou is the world's first airport therapy pig.

To see LiLou turn on the charm, check out the video below.

[h/t Reuters]

Sssspectacular: Tree Snakes in Australia Can Actually Jump

sirichai_raksue/iStock via Getty Images
sirichai_raksue/iStock via Getty Images

Ophidiophobia, or fear of snakes, is common among humans. We avoid snakes in the wild, have nightmares about snakes at night, and recoil at snakes on television. We might even be born with the aversion. When researchers showed babies photos of snakes and spiders, their tiny pupils dilated, indicating an arousal response to these ancestral threats.

If you really want to scare a baby, show them footage of an Australian tree snake. Thanks to researchers at Virginia Tech, we now know these non-venomous snakes of the genus Dendrelaphis can become airborne, propelling themselves around treetops like sentient Silly String.

That’s Dendrelaphis pictus, which was caught zipping through the air in 2010. After looking at footage previously filmed by her advisor Jake Socha, Virginia Tech Ph.D. candidate Michelle Graham headed for Australia and built a kind of American Ninja Warrior course for snakes out of PVC piping and tree branches. Graham observed that the snakes tend to spot their landing target, then spring upward. The momentum gets them across gaps that would otherwise not be practical to cross.

Graham next plans to investigate why snakes feel compelled to jump. They might feel a need to escape, or continue moving, or do it because they can. Two scientific papers due in 2020 could provide answers.

Dendrelaphis isn’t the only kind of snake with propulsive capabilities. The Chrysopelea genus includes five species found in Southeast Asia and China, among other places, that can glide through the air.

[h/t National Geographic]

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