Iberian chiffchaff Iberian chiffchaff The Iberian chiffchaff ("Phylloscopus ibericus") is a species of leaf warbler endemic to Portugal, Spain and North Africa, west of a line stretching roughly from the western Pyrenees via the mountains of central Spain to the Mediterranean. The name "chiffchaff" is onomatopoeic, referring to the repetitive "chiff-chaff" song of the common chiffchaff ("Phylloscopus collybita"). There are similar names in some other European languages, such as the Dutch "Tjiftjaf", the German "Zilpzalp" and Welsh "siff-saff". The genus name "Phylloscopus" is from Ancient Greek "phullon", "leaf", and "skopos", "seeker" (from "skopeo", "to watch"). The specific "ibericus" is Latin for "Iberian".
Genomic evolution of birds bird bones. Something similar occurs with the respiratory system. In mammals, the total inner volume of lungs changes during ventilation. However, this does not happen in birds. They make the air circulate through their lungs by contracting and expanding their air sacs. Five genes are involved in this process in mammals and birds. Feathers are one of the most characteristic features of birds, alongside with the beak. Feathers are formed of α- and β-keratins. Compared to reptiles and mammals, α-keratin protein family has been reduced in birds, whereas β-keratins has expanded enormously. Since every major bird lineage possess at least