A new study found that domestic cats have smaller brains than the wild cats from which they evolved. According to the researchers, brain areas associated with arousal and fear are smaller in the subspecies that enjoy the security of human homes
By Katia Aginov, Angle - a news agency for science and the environment
There is no doubt that cats are an integral part of a person's environment. The lucky ones are pampered in our warm homes, and receive food, affection, veterinary care and protection from danger - and give their loved ones calm and joy in exchange. Others fill the streets, where they suffer from the weather conditions and the threats of the city, but sometimes also benefit from the kindness of volunteer feeders and caregivers.
New findings reveal that proximity to humans affects cats (and not just by learning to open door handles that don't exist in the wild and using their animalistic climbing skills to reach the top shelf in the closet), and according to A new Austro-British study, cats' brains have become smaller since they were domesticated by man.
In the new study, published in the scientific journal Royal Society Open Science, the researchers compared the skull volumes of the domestic cat, the European wild cat (Happy New Year(African wild cat)Felis lybica) and hybrids of domestic cats and European wild cats from Scotland. The two wild species tested are very similar to domestic cats (although they are slightly larger - mainly the European wildcat - and are not domestic animals), with recent genetic evidence confirming that the African wildcat is the ancestor of the domestic cat. The researchers examined a total number of 103 skulls, and measured the volume and length of each skull and the length of the palate.
The argument that the brains of domestic cats are smaller has already been heard in the past, and in the new study the scientists reproduced studies conducted on the subject in the 60s and 70s, so their findings update the outdated information that existed in the field and provide new data.
Decrease in areas of arousal and stress in domesticated animals
According to the findings of the new study, domestic cats do have smaller skulls than the wild cats tested - which, according to the researchers, indicates smaller brains. The skull volume of the cats that are hybrids between domestic cats and wild cats also strengthens the findings, and was found to be smaller than that of the wild subspecies, and larger than that of the domestic subspecies.
The researchers also found that the length of the palate in the skulls of domestic cats is shorter than that of European wild cats - but longer than that of African wild cats. This finding surprised the researchers, who expected that the palate would also shrink with the contraction of the skull.
"The skull has two main functions: the first is related to the brain and the senses - and the second to the jaws, which are responsible for collecting food," explains Prof. David Eilam from the School of Zoology at Tel Aviv University. "In carnivores that live in the wild, the brain and senses are indeed more developed." According to Elam, this is expressed in the hunting and survival abilities of the predators in the wild, which according to him are much less developed in domestic cats.
The researchers explain that according to new theories, the domestication of cats led to a reduced production of neural crest cells in their brains, which contributed to the reduction of the brain and skull. These cells are associated with arousal and fear, so domestication led to a decrease in both of these responses - and to more "tame" animals. The reduction also led to changes in responses to stress, as well as in the general shape and structure of the body.
"When you put a cat in the company of a person, it has food available, so it doesn't need hunting and survival skills," claims Elam. According to him, the situation is very different with dogs. "Dogs actually acquired more developed cognitive abilities because of their proximity to humans," he says. According to him, as part of the dogs' daily interaction with humans, they were exposed to actions and a more complex way of thinking through him, and developed abilities accordingly. "In experiments that compared the problem-solving ability of wolves to that of dogs, for example with the help of tests in which the animal is required to understand that it is necessary to press a pedal to get food, it was found that dogs actually have much higher abilities." According to Elam, this did not happen with cats, whose interaction with humans is different.
According to Elam, during the evolution of each species, it undergoes adaptation to certain needs - and as a result, gives up other abilities. "In gorillas, for example, brain development depends on the social environment - because they have no enemies, so they don't need the abilities to survive against them."
The cat is good for health
It should be noted that humans are also affected in different ways by being close to domestic cats. Living in a cat cage has been found to be associated with a lower chance of heart attack and cardiovascular disease (including stroke), and it lowers blood pressure and heart rate. They were also found to be associated with a lower chance of morbidity in certain types of cancer, andIn asthma in children. In addition, cats eliminate pests - including those that transmit serious diseases to humans. Beyond that, cats provide company and support to many, whether these are people who suffer from loneliness - or simply those who enjoy being comforted by furry company.
What is the brain size of the lab rat?
Have domestic cats become less developed creatures than their wild relatives? Not necessarily. "Brain volume is a measure of a developed brain - but there are also other measures of brain development, so it is impossible to say that a larger brain is necessarily more developed," says Elam. Beyond that, according to him, the parameter of body weight must also be taken into account. "In humans, for example, men's brains are larger than women's - but if you look at the brain in relation to body weight, then the female brain is larger."
A smaller brain in size compared to animals in the wild is a well-known characteristic of domesticated mammals, and the trend has also been observed in sheep, dogs, rabbits and more. However, the researchers who conducted the new study claim that comparisons of brain sizes are often based on old literature, and that in many studies comparisons were made between domestic animals and species that are no longer considered to be their ancestors. According to them, they plan to continue to investigate the matter, and to reproduce More old studies, who also dealt with other domesticated species. Elam suggests expanding the research also to more recently captive species. "It would be interesting to study the difference between rats in the wild and laboratory rats, for example," he concludes.
Editor's Note: Feral (and fed) domestic cats are also the most dangerous predator for birds and small mammals. The conclusion today is that those who want to raise a cat - should only do so indoors. Expansion coming soon.
