A study has concluded that the brains of domestic cats have shrunk during the time that they have been domesticated. And having shrunk I have concluded that domestic cats are probably more stupid today than they were at the time of the Ancient Egyptians. And I suspect that they will go on becoming a bit more stupid over the next few thousand years. We’re going to end up with little balls of fluff that are charming but quite thick 😊.
The researchers stated:
“Two characteristics often used to describe changes to domestic animals are a reduction in brain size and snout length. Wilkins et al. suggested that a neural crest cell deficiency, caused by selection for tameness, is the underlying factor responsible for these characteristics. Our results on cranial volume reduction in domestic cats are in line with the neural crest cell hypothesis and previous reports.”
To restate the above, these scientists, under their current research, confirmed what had been found earlier which is, as mentioned, that selection for tameness reduces brain and skull size.
The reasoning behind this is that over the approximately 10,000 domestication there has been informal and sometimes formal selective breeding for “tameness”. In other words, people have preferred cats which are very pliable and agreeable. Cats have lost their wild inheritance. And it is found that the natural selection of the tameness has led to the production of fewer neural crest cells. These cells are linked to excitability and fear. This has led to a smaller skull and a smaller brain size. Neural crest cells are involved in processing and responding to threats.
When you think about it the process of dumbing down (my words) is actually predictable even to a non-scientist. I will also state that (and this is my personal opinion) the wildcats are far more challenged on a day-to-day basis in order to survive. Their brain is used far more actively. This, I would argue, creates neural pathways which makes the cat more intelligent. They are more switched on. Cat domestication in many ways turns a cat off. Hence long snoozes and rest periods in which they kill time.
The news media consistently reports how domestic cats sleep all day and do nothing. This is the point I am making. They are doing nothing because they are not challenged. They are not stimulated. This goes back to what is consistently stated by cat behaviourists that cat caregivers need to provide their cat with an environment which can stimulate them and which as near as possible replicates their natural life. Jackson calls it ‘cat mojo’ or ‘the raw cat’ within the domestic cat that needs to be activated.
The study has limitations, they say. The new research published in the Journal Royal Society Open Science concerned replicating studies on cranial volumes and domestic cats published in the 1960s and 1970s which compared wildcat, domestic cats and wildcat hybrids. I’m not sure what they mean by “replicating”.
It seems that they re-evaluated the data collected and analysed by earlier scientists. So, for example, to quote the scientists: “Since the most complete comparison across species was presented over basal skull length by Hemmer, we decided to use basal skull measurements combined with cranial volume measurements for our own data collection in this replication study.”
They assessed the size of the skulls of domestic cats, European wildcats and African wildcats (North African wildcat). The domestic cats have smaller skulls and brains than both European and African wildcats. And the wildcat hybrids had skull size and brain size which was in between that of the domestic and wild cats.
The wildcat hybrids, particular the first filial cats, are known to be more intelligent than regular domestic cats. These findings are no surprise to me.
The team of researchers come from the University of Vienna and National Museums Scotland. The same process of shrinkage in skull size and brain size has been seen in dogs, sheep and rabbits. They state that earlier research had become outdated and in some instances was based on inaccurate representations of an animal’s ancestry. That’s why they decided to do this review.
I have found the study which is called: Cranial volume and palate length of cats, Felis spp., under domestication, hybridization and in wild populations. The researchers are: Raffaela Lesch, Andrew C. Kitchener, Georg Hantke, Kurt Kotrschal and W. Tecumseh Fitch.
The entire study, not just the abstract, is available for reading without payment. They also measured the “snout length” of domestic cats compared to wildcats. They found that domestic cats have longer palates compared to their ancestral species. Although the differences were masked by the differences in individual body size.
A factor which muddies the water is that the researchers don’t know how the wildcat has changed over thousands of years. These studies compare current or nearly current wild cat species to the domestic cat but not current domestic cats to the “true ancestral population”. This they say is a “confounding factor”.
