Scientists: the brain in cats has decreased due to domestication

The brain volume of domestic cats is less than that of European and African wild relatives. Such changes in morphology are caused by the proximity to people, think scientists from Austria and Scotland.

A study published by the University of Vienna and the Department of Natural Sciences at the National Museum of Scotland states that cats (Felis catus) were domesticated about 10,000 years ago. years ago. It is genetically confirmed that their ancestors were wild cats from Europe and Africa, and the evolutionary process proceeded rather slowly.

Scientists analyzed the morphological features of wild and domestic cats, as well as their hybrids bred in USA: Bengals obtained from crossing with Bengal cats proper, and Savannahs - descendants of African servals. As a result, they found that the volume of the skull and the size of the brain in wild species are much larger than in domestic ones, and hybrid breeds are approximately in the middle in this regard. A similar trend is also observed in sheep, dogs and rabbits.

Researchers believe that during domestication, people selected the most calm and easily tamed cats. In such animals, the number of neural crest cells was less, and this feature was fixed in the process of evolution.

Migrating neural crest cells are associated with excitability and fear processes. During embryonic development, these cells develop into various body structures, including the adrenal glands, which release adrenaline in fight-or-flight responses. Neural crest cells are also responsible for the size of the brain.

The brighter the cat reacts to stress, the more adrenaline is released into her blood. Accordingly, if the cat is calm, then the adrenal glands produce this hormone in small quantities. This means that the animal had fewer neural crest cells, and as a result, its brain is more compact.

To similar conclusions earlier came and scientists from the Humboldt University in Berlin. They suggested that humans were subconsciously selecting cats with neural crest defects. Such animals were more docile and non-aggressive.

Research into the size of the brains of cats has been carried out since the 1960s. But often they were based on old or inaccessible data, or on comparisons with wild species that are no longer considered the progenitors of modern pets.

The new work covers more information. But scientists admitted that they only had data on living species. Perhaps if we can study the DNA of the ancient ancestors of domestic cats, it will be possible to get a more complete picture.

Also, researchers do not agree with the theory that cats are only partially domesticated today - at least in comparison with dogs. They emphasized that cats came to people and stayed at home, on farms and on ships, not only because they were looking for an easily accessible source of food - they actually form a connection with the owner. And people, in turn, began to domesticate cats because of their temperament.