Mice Change Their Appearance as a Result of Frequent Exposure to Humans
media.uzh.ch
media.uzh.ch
Or that when the mice population increases the animals just fight more. Domestic mouse males fight and bite other males. Mother with litters will attack males also. More animals in the same place = more scars by bites, and this could easily lead to an increase on white (regrown) hair patches. A simple explanation that does not depend on human contact. Is normal in birds to create white feathers after a predation event to quickly replace missing ones and cover bald patches.
And another explanation could be that when the mice population increases, their individual size decreases because there are less food for each one (and different hormone interactions non necessarily human related). If we extract some of those mice and put it in a new cage subject to the same human manipulation but with a more diverse sources of food, would the average skull size quickly increase again? Would the animals with white patches decrease? I bet that yes.
One of the problems with the article is that does not try to discard those explanations. A simple check to investigate if white spots are linked to sex or age would help. A check for scars in those patches would positively help us to understand what is happenning. It does not mean necessarily harming the mice, they could just rasurate some white patches and take a look.
We are concluding that animals sort of "deliberately increase" their "cuteness" to please humans but this conclusion is not justified. What if aggression is just being increased as response to animals being marked with strange human odour?. This kind of articles should discuss at least some of those alternative explanations.
It strikes me that that situation represents a selection pressure, because mice that are more afraid of humans, are likely to avoid a place where they are regularly present, and thus lose the advantage of the risk-free meal ticket these particular humans are providing.
https://en.wikipedia.org/wiki/Domesticated_red_fox
"Russian scientists achieved a population of domesticated foxes that are fundamentally different in temperament and behavior from their wild forebears. Some important changes in physiology and morphology became visible, such as mottled or spotted colored fur. Some scientists[citation needed] believe that these changes obtaining from selection for tameness are caused by lower adrenaline production in the new population..."
These younger looking animals will look less threatening, and might even have traits similar to human young (relatively larger eyes, etc.)
So it might be more that cuteness is related to neoteny which is related to domestication and other situations where animals might be seen as less threatening. Definitely doesn’t answer the whole question though.
> Often, juvenile behaviors are selected for in order to domesticate more easily a species; aggressiveness in certain species comes with adulthood when there is a need to compete for resources. If there is no need for competition, then there is no need for aggression. Selecting for juvenile behavioral characteristics can lead to neoteny in physical characteristics because, for example, with the reduced need for behaviors like aggression there is no need for developed traits that would help in that area.
If the results of a newly-introduced selection pressure can be explained by darwinism / natural selection, then surely so can the results of a removal of selection pressure.
For example, if there are genes that result in lowered fear or agression, and that leads to fewer offspring for wild mice, they will have a lower frequency in a wild mouse population than in a population where they don't lead to fewer offspring. I'm no expert, but it doesn't seem like this particular article requires any additional mechanisms beyond natural selection.