Prioksko-Terrasny Nature Reserve covering 4945 ha, 134 species of birds from 14 orders (Ciconiiformes, Anseriformes, Falconiformes, Galliformes, Gruiformes, Charadriiformes, Columbiformes, Cuculiformes, Strigiformes, Caprimulgiformes, Apodiformes, Coraciiformes, Piciformes, Passeriformes) had been registered by 1991. Later 5 more species were observed here. Thus, by the present time, the list of species of birds registered in the Reserve numbers 139 species. About 55% from them are Passerines. Most of birds of the Reserve belong to migratory breeding species or to nomadic breeding species. Some species are vagrants in the Reserve and in the Moscow Region (nutcracker Nicifraga caryocatactes (L.), etc.). Birds, nesting in central parts of Russia
Genomic evolution of birds several modifications and deletions which occurred in the exons of the genes implicated in the formation of enamel and dentine. It is thought that the common ancestor of birds already lacked mineralized teeth, and that later genome changes pushed the situation to the current status. Also, birds have the best vision system known in vertebrates. They have a higher number of photoreceptors, and most birds are tetrachromats. The only exception are penguins, which have only three functional opsin genes (and hence are trichromats). This exception could be related to the aquatic lifestyle, since marine mammals have also lost either one