The type of natural selection the trait of having thick white feathers in snowy owls is directional selection. Over time the snowy owls will get more and more used to having extremely low temperatures so their adaptation for maintaining themselves warm (thick feathers) will get more and more common because of the need to survive. More information about the snowy owl's adaptation will be mentioned further into this page.
Evolution
In general, with owls the certain areas of the topic of evolution are not very "confirmed". Currently there is not much evidence that could completely determine how the snowy owl evolved to the animal it is now. There was very minimal information about owls and snowy owls when they first came to existence. However information that was found included that some scientists have concluded owls came from the ostrich, others suggest they evolved from a variety of bird species. It all ends up being traced back to dinosaurs as seen in the image above many birds have the common ancestor of the Tyrannosaurus Rex. Moving forward, one thing that’s certain is that owls evolved into different types of species there are owls in deserts, the arctic and forests meaning they had to have evolved and adapt to their new surroundings. Most of the owls evolved from the True Owl (Strigidae). As of 2014, the population of snowy owls continue to stay strong with the population increasing. These owls are protected and according to a Tech Times article it is rare for snowy owls to be seen in large quantities. In the United States for the past two years there have been large numbers of snowy owls seen, from 170 to over 200. This increase was most likely due to the increase of food sources. The snowy owl’s adaptation of having sharp eye vision and strong claws have come to the snowy owl’s advantage and has helped increase their population.
Speciation Event: As stated before, the evolution of owls is very hard to find solid evidence on. Without that you cannot get much evidence on the evolution of the snowy owl. With speciation, the formation of a new species In the course of evolution, it is definitely harder to find information because so many of these changes happened very early in time. There are still examples of speciation with owls that do have a lot of evidence to be backed up with. In owls, specifically the Northern Spotted Owl and the Mexican Spotted Owl multiple regional changes that were different genetically and physically. These two subspecies were living in different location and showed changes and differences due to the different environments. This was an example of how the speciation occurred through geographical isolation.
Subspecies A: The snowy owl has no subspecies but owl’s in general of course, do. One of the most popular known kind of owl to become extinct is the Laughing Owl. The laughing owl was in the same family as the snowy owl. The laughing owl had to adapt to a new environment of limestone cliffs and had to adjust to their change of diet. The Laughing Owl had have stronger legs in order to hunt for rodents by foot. The Laughing Owl was stated to be extinct in the early 20th century. The laughing owl became extinct because it was a common prey for many mammals and didn't have much defense other than their strange shrieks and “laugh”. Humans were attracted to this animal and they began hunting them for showcase purposes. Subspecies B: The arctic owl (Nyctea scandiaca) evolved from the Great Horned Owl (Bubo virginianus). When the brown owl was isolated in the cold ice caps, it had to survive so they responded to their new environment like growing thicker feathers, being colored white to camouflage with the snow, and having eyes that adjusted better to the climate/settings of their new environment. This having of happened, the snowy owl evolved into the species it is today. This species along with 3 other are subspecies of the Bubonini species and belong to the Strignae family.