Quirks and Quarks

5 feline facts to help see your cat in a new light

Research offers new insights into our feline friends' biology and behavior.

Research offers new insights into our feline friends' biology and behaviour

A tabby cat with green eyes lays down with its ears lowered, looking at the camera.
African wild cats are the closest genetic relatives of our domestic Felis catus. (William Laur/Lincoln Journal Star/AP)

Originally published on Dec. 1, 2023.

Cats have lived alongside humans for millennia, but there's still much we don't know about our companions. How do cats purr? Why do they look so annoyed all the time? And when and where did cats begin sharing homes with humans? 

Part of the issue with finding the answers to these questions is the notoriously secretive nature of domestic cats and their unwillingness to do what they're told — something that makes studying cats in a laboratory setting quite challenging. But advances in technology and research methods in recent years have helped to shed light on some cat behaviour, pinpoint the origins of the species we know as the domestic cat, and even find a cure for a fatal feline disease.  

Here's some of the latest science about our feline companions.

Cats' faces are more expressive than you think

Humans have been trying to decode the meaning of their feline friends' facial expressions for a while, making some progress in studies of cat faces in interactions with humans. But what are their faces doing around other cats? To find out, researchers recorded videos at a Los Angeles, Calif., cat café to study the facial expressions the animals make while interacting among themselves. 

Using a facial muscle coding system, the scientists discovered that cats make 276 distinct facial expressions using 26 unique facial movements, such as parting their lips, licking their nose or squinting their eyes. Brittany Florkiewicz, a co-author of the new study, said the majority of those expressions could be categorized as either friendly or unfriendly. "We were able to find evidence for something called a 'play face,'" she told Quirks & Quarks host Bob McDonald. "And we actually have current studies that show that big cats are capable of producing these play faces as well."

Florkiewicz, who has also studied ape facial expressions, said she was impressed by the range of expressions found in cats, comparable to over 300 expressions she has previously identified in chimpanzees. "It was really interesting to think about how domestication has shaped that facial expression repertoire, and then thinking about comparisons that we could potentially make with other species," she said.

A cat is being brushed by a person wearing blue medical gloves, while another person holds the cat's face.
Cats can make low rumbles indicating pleasure while being groomed by their owners. Scientists say unique anatomical features on cat vocal folds are responsible for the low-frequency purring sounds. (Denys Kurbatov/Shutterstock)

Cats are built to purr

Regardless of what their face looks like, a telltale sign of a happy cat is the signature purr. But something that has puzzled scientists is how an animal as small as a domestic cat can produce sounds at such low frequencies. 

Tecumseh W. Fitch studied the physiology of cat larynges — the organ in the back of the throat involved in breathing and sound production, also known as the voice box — to figure this out. In his research, he identified a pair of fatty pads that help slow down the vibration of the vocal folds to make the low-frequency rumbling. 

"So what we think is that the cat is using one part of its vocal folds to produce… sounds like meows. And only using the full vocal fold with these fat inclusions to make for a lower-frequency purrs," he told Quirks & Quarks.   

These results, published in Current Biology, also challenge the common theory of the mechanics of purring. "What was thought until our study for cats is that … each pulse of the purr was actually accompanied by a muscle twitch that had to be driven by the cat, by a neural signal from the cat's brain," Fitch said. "And what we were able to show is that, that's not necessary for purring to occur."

Cat hair can help solve crimes

Here's a fact that doesn't need a research paper to back it up: cat hair gets everywhere. And while this may be bad news for your stylish all-black outfits, it's good news for forensic scientists. 

The potential of using cat hair to solve crimes has been known for some time now. In a 2023 U.K. manslaughter case, cat hairs left on the victim were matched to those found in a suspect's home, resulting in a conviction. But there are some challenges to using cat hair to identify wrongdoers.

Cat hair doesn't contain as much genetic material as a swab of saliva or a drop of blood, "so we have to look at another kind," researcher Mark Jobling told Quirks & Quarks. "And that kind is called mitochondrial DNA."

In a paper published in the journal Forensic Science International: Genetics, Jobling and his team describe how they were able to extract mitochondrial DNA from cat hair. Jobling said this test "can work with as little as a single cat hair" and hairs that are over 20 years old. This could be useful in cold cases where cat hair is included in the evidence, since unlike blood or saliva, DNA in hair degrades more slowly over time.

Cats can get sick with coronaviruses — and better with COVID-19 antivirals

The COVID-19 pandemic brought extra concerns for cat owners too, as reports emerged of tigers and domestic cats testing positive for the virus. But long before SARS-CoV-2, there was a different coronavirus plaguing the feline population. "The standard cat coronavirus, it's all over the world. And most cats, if they go outside, they catch it," said feline infectious disease specialist Danielle Gunn-Moore. 

For most cats that catch this virus, it shows up as some mild diarrhea. But in a small percentage of animals, the virus mutates into a deadly disease called feline infectious peritonitis (FIP). 

A street scene with an elderly man sitting at an outdoor cafe table, with two ginger cats passing him on the street.
The island of Cyprus is home to thousands of unowned cats, which have been devastated by a deadly new strain of the coronavirus responsible for feline infectious peritonitis, or FIP. (AP Photo/Petros Karadjias)

Until recently, the FIP diagnosis was a death sentence. But when antiviral medicine for SARS-CoV-2 became available, it turned out that these drugs are incredibly effective as FIP treatment. When Gunn-Moore and her colleagues tested the antiviral drugs in a population of over 300 cats, treatment was effective in 85 per cent of the animals. "It's like fate has given us the most wonderful gift of ... something we can treat this devastating disease with," Gunn-Moore said. 

And it came at just the right time, as a particularly deadly strain of the cat coronavirus was devastating the numerous population of feral cats in Cyprus. Gunn-Moore and her colleagues are now building on the success of the antiviral treatment to develop a more effective vaccine against FIP.

Even when they're curled up in your lap, cats have 'one paw in the wild'

Analysis of ancient cat DNA — including numerous cat mummies found in Egypt — has helped scientists conclude that the the domestic cats species, Felis catus, originated in the North African wild cat. But as author Jonathan B. Losos explores in his new book, The Cat's Meow: How the Cats Evolved from the Savanna to Your Sofa, much of our cats' behaviour remains on the wild side. 

Two cats eating from plates with piles of food
Two feral cats eat some food left by local residents in New Brunswick. Feral cat colony members are known to be very friendly to each other, grooming, playing together, and nursing each other's young, author Jonathan Losos says. (Submitted by Jo-Ann Cook)

"One thing about unowned outdoor cats is they very quickly revert to their wild existence," Losos told Quirks & Quarks. "They have, if you will, one paw still in the wild, because it's very easy for them to revert and basically go back to living like their ancestors did, hunting and getting by quite well." 

Studies of feral cat colonies also show an internal hierarchy different from most other species of cats, wild or domestic. "Cats have a reputation of being aloof loners that live by themselves ... not being very friendly to each other. It turns out that at least in some circumstances, that could not be further from the truth," Losos said. "Domestic cats, when they're living at high densities, form into prides just like lions." These groups groom each other and play together, and even nurse each other's young.

ABOUT THE AUTHOR

Olsy Sorokina

Journalist

Olsy Sorokina is an online journalist and radio producer, currently sharing fascinating science on CBC Radio's Quirks & Quarks.