Feathers are modified as scales. According to the history, birds which have feathers are the descendants of the dinosaurs which have scales.
That's why feathers are categorized as scales in the present record according to studies. <span />
Purebreed is where both parents are the same breed to produce an offspring of the same breed.
Evidence for evolution, in other words evidence of common descent, include fossils, which have shown a (fairly) steady change in morphology over time for some species. An example would be horse hooves: we have fossils that show when they were still three toed, then two toed, then one toe in our present day horses. Another piece of evidence is vestigial organs. An example of vestigial organs is wings in some flightless birds, such as the kiwi. Their ancestors used it in order to fly across the marine barrier into New Zealand, but natural selection and random genetic drift made them quickly lose the ability to fly. Nonetheless, they still have their wings, however small. It can be assumed that eventually, their wings would be reduced to small stubs fused to other nearby bones, as has been observed in their cousins.
