When you hug, hold, squeeze, and pet your cat, you’re probably vaguely aware, maybe just in the back of your mind, that you’re actively trying to improve your quality of life by engaging in a pleasant activity. But something might be happening on a deeper, hormonal level that boosts not only your mood but your cat’s, too.

According to research published in iScience by a Kyoto University team, previous studies on whether cats actually make our lives better have been a bit of a mixed bag. There’s enough science to strongly suggest that dogs offer health benefits that stick around for quite a while. But research on cats’ health benefits, like the animals themselves, is complicated and inconsistent.

To figure out why cat ownership’s perks are harder to pin down, the researchers tracked 19 human and cat pairs for a month using Bluetooth tracking beacons and urine samples to check in on any biological effects.

Your Cat’s Brain Chemistry Could Be Affecting Your Mood, New Research Suggests

They found that simply owning a cat doesn’t magically turn your brain into a blissful utopia. But something fascinating is happening, and you need to be in close physical proximity to your cat to reap the benefits.

The study found a direct hormonal link between humans and cats: higher oxytocin in cats correlated with lower cortisol and fewer negative vibes in humans. Oxytocin is the hormone associated with bonding, and cortisol is the hormone that triggers stress.

In other words, the more your cat feels your bond, the less stress you’ll feel in turn. The researchers found such a close connection between the two that a cat’s oxytocin levels tracked an owner’s bad mood more closely than the owner’s own biochemistry did.

This is, of course, a good example of small-sample-size theater, and it all amounts to correlation rather than causation, but excuse me for snuggling your kitty just a little bit more tightly tonight.

The post Why Spending Time With Your Cat Feels So Good, According to Science appeared first on VICE.

You’ve probably seen it with your own eyes before, but a research team that published its findings in the journal Science says it noticed it at an epigenetic level: big dogs age faster. Chihuahuas, for as obnoxiously yappy as they are, seemed to last forever, while Great Danes, those big lovable galoots, give you about a decade before they cross the rainbow bridge.

Researchers at Arizona State University analyzing DNA from nearly 900 dogs in the Dog Aging Project finally know why big dogs don’t last as long. It all has to do with rogue “jumping genes.”

Scientists Say ‘Jumping Genes’ Could Explain Why Big Dogs Have Shorter Lives

Inside dog DNA, a specific class of “jumping” genes called LINE1s exists. Normally, a biological process called DNA methylation stamps chemical tags onto these genes to keep them locked down, but as big dogs age, that regulatory process falls apart and LINE1s start shaking loose, jumping between chromosomes, shredding DNA apart in the process, thus causing instability in the cells, triggering inflammation and cancer.

This happens to all dogs, but in big dogs it happens catastrophically and early. Giant breeds shed roughly 35 percent more LINE1 methylation per year than smaller dogs that fit in a purse.

Or, to put it less scientifically: there’s just too much dog for their bodies to keep up with. Humans specifically bred big dogs for their rapid growth, but that early growth leads to a genetic mess later in life, as their biological clocks essentially run twice as fast as a smaller dog’s.

The researchers think these out-of-control jumping genes could be a universal mammalian aging mechanism, and that learning more about them could eventually help us learn a little about ourselves, too, since dogs get a lot of the same age-related diseases that we do, largely because we share environments.

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