Tag Archives: Expression

Most people struggle to read cats’ expressions, but “cat whisperers” don’t

Researchers at the University of Guelph (UoG) found that you’re probably bad at reading the emotions in a cat’s face — unless you’re a “cat whisperer”.

Image via Pixabay.

Most people have a hard time picking up on the emotions hidden in a cat’s facial expression. Cats use non-vocal cues such as body pose and facial expressions to communicate a wealth of information, but these behaviors and grimaces tend to be very subtle, flying under the radar of most humans. Some people, new research has found, are very good at understanding these cues — a group the team calls “cat whisperers”.

Overall, women and people with veterinary experience were better than average at recognizing a cat’s expression, even those that said they don’t feel a strong attachment to cats.

Dropping hints

“The ability to read animals’ facial expressions is critical to welfare assessment. Our finding that some people are outstanding at reading these subtle clues suggests it’s a skill more people can be trained to do,” said Prof. Lee Niel, who led the study with Prof. Georgia Mason, both from UoG’s Campbell Centre for the Study of Animal Welfare.

The team explains that previous research into this topic only focused on expressions of pain, not fear, frustration, or positive emotions.

For their study, the team recruited more than 6,300 people from 85 countries. The participants were asked to watch 20 short online videos of cats from a collection of 40 videos (most of them from YouTube) and then complete a series of online questionnaires.

These videos showed cats expressing positive emotional states (usually involving situations that the animal sought out, just as receiving a treat or a pat) or negative states (cats retreating, fleeing, or experiencing health problems), but none showed expressions of fear, such as flattened ears or bared teeth — the team explains that these expressions are already widely understood by people. The videos focused on the cat’s face (eyes, muzzle, and mouth).

Each participant was asked to indicate whether the cat was experiencing a positive state, a negative one, or if they were unsure as to what the animal was feeling.

Most participants said they found the test challenging, and the results reflected this. The average score was 12 out of 20 correct answers, which is just about as accurate as a coinflip. However, 13% of the participants scored around 15 out of 20 correct answers: these are the “cat whisperers”. Women were more likely than men to be cat whisperers, as were veterinarians or vet technicians compared to other professions. Overall, younger adults tended to score better than older adults.

“The fact that women generally scored better than men is consistent with previous research that has shown that women appear to be better at decoding non-verbal displays of emotion, both in humans and dogs,” said Mason, who worked on the study along with post-doctoral researchers Jenna Cheal and Lauren Dawson.

In a rather surprising find, whether or not a participant reported a strong attachment to cats had no bearing on how well they scored. The team says their findings suggest that it is possible to train people to better read cats’ facial expressions. You can test your ability to read a cat’s expression using this test the team put together.

“This is important to be able to do because it could help strengthen the bond between owners and cats, and so improve cat care and welfare,” said Niel.

The paper “Humans can identify cats’ affective states from subtle facial expressions” has been published in the journal Animal Welfare.

Python.

A new study explains how snakes lost their legs

Efforts to understand how changes in the genome lead to changes in phenotypes is showing us why snakes don’t have legs.

Python.

Image via Pixabay.

While snakes and lizards belong to the same order (Squamata), they differ in one obvious aspect: snakes do not have limbs. New research is looking into the genetic changes that led to this outward difference. The study, led by Juliana Gusson Roscito at the Max Planck Institute for Molecular Cell Biology and Genetics in Dresden, Germany, also analyzed eye degradation in certain subterranean mammals.

Different within, different without

“The research consisted of an investigation of the genomes of several species of vertebrates, including the identification of genomic regions that changed only in snakes or subterranean mammals, while remaining unchanged in other species that have not lost their limbs or have normal eyes,” Roscito said.

Mammals with degraded visual systems seem to have shed certain genes from their genomes — mainly those associated with the formation of the crystalline lens and photoreceptor cells in the eyes. This process was very likely gradual, taking successive mutations during the evolutionary process but, eventually, these genes completely lost their ability to encode proteins. However, Roscito says, this isn’t what happened to snakes — they haven’t lost the genes associated with limb-formation.

“To be more precise, the study that sequenced the genome of a snake did detect the loss of one gene, but only one,” she adds. “Therefore, the approach we chose in our research consisted of investigating not the genes but the elements that regulate gene expression.”

Gene expression — whether a gene is ‘active’ or not — depends on regulatory elements that are outside of the gene itself. These basically allow or block the information inside the gene to be transcribed into RNA and then be carried off to generate a protein. This process is regulated by cis-regulatory elements (CREs), sequences of nucleotides in DNA placed near the genes they regulate. These CREs can significantly alter a genome’s functionality via the genes they block or enable.

“A regulatory element can activate or inhibit the expression of a gene in a certain part of the organism, such as the limbs, for example, while a different regulatory element can activate or inhibit the expression of the same gene in a different part, such as the head,” Roscito explains.

“If the gene is lost, it ceases to be expressed in both places and can often have a negative effect on the organism’s formation. However, if only one of the regulatory elements is lost, expression may disappear in one part while being conserved in the other.”

However, it’s pretty difficult to accurately identify CREs. Genes all follow a certain structural pattern, having base pairs at each end of the gene — so they’re easy to delineate. CREs have to be identified indirectly, usually by comparing DNA sequences from different species. That’s exactly what the team did for this study: they compared the genomes of snakes with those of various other reptile and vertebrates (that have limbs). As “genome sequences for reptiles with well-developed limbs are scarce”, the team writes, they sequenced and assembled the genome of Salvator merianae, the tegu lizard, themselves. This is “the first species of the teiid lineage ever sequenced,” the authors add.

Gold Tegu.

The gold tegu, Tupinambis teguixin.
Image credits Joel Santana.

Using this genome as a reference, the team looked at the genomes of several other species. These included two snakes (boa and python) three other limbed reptiles (green anole lizard, dragon lizard, and gecko) three birds, an alligator, three turtles, 14 mammals, a frog, and a coelacanth (a very rare type of fish). They ‘aligned’ these 29 genomes together and used that as a basis for their analysis.

Armed with 5,000 possible candidates for regulatory elements in the DNAs of these species, the team looked at the genomes of several species of snakes. They managed to narrow down the search to a set of CREs whose mutation may have led to the disappearance of limbs in snakes.

“There are several studies concerning a well-known regulatory element that regulates a gene that, when modified, causes various defects in limbs. Snakes have mutations in this CRE. In a study published in 2016, the mouse CRE was replaced with the snake version, resulting in practically limbless descendants,” Roscito says. “This was a functional demonstration of a mechanism that may have led to limb loss in snakes.”

“However, this CRE is only one of the regulatory elements for one of several genes that control limb formation. Our study extended the set of CREs. We showed that several other regulatory elements responsible for regulating many genes have mutated in snakes. The signature is far more comprehensive. An entire signaling cascade is affected.”

The paper “Phenotype loss is associated with widespread divergence of the gene regulatory landscape in evolution” has been published in the journal Nature Communications.