Cats are one of the most popular domesticated species in the world. It also appears that our generous care towards them has had a significant impact on their physical makeup. A recent study took a look at Viking archaeological sites across Denmark and specifically the cat skeletons found in them. They found that the bones showed cats today are 16% larger than the cats from the Viking age.
At that time, cats were not domesticated but instead raised to control pests or as a source of furs. Marks on the bones were found indicating that the coat was removed and fur coats made from cats were also found at other sites. Since then, people have certainly taken far greater care of their pet cats, and the archaeological findings bear that out. Discussions still occur about the origin of feline domestication, but the consensus is there were two distinct waves, one from Southwest Asia and another from Egypt.
Initially difficult to tame, due to their antisocial behavior, cats have an advantage over other similar creatures as their facial features mimic human babies. Thus, they were perceived as endearing rather than as a pest. However, it is still unclear if cats size change indicates the effect of better care or a genetic shift. To confirm that, further DNA testing will need to be done on more uncovered specimens.