Birds In Flight By Roy Hancliff

He was always been interested in photography, now he has the time to dedicate to this hobby. His faithful photographers assistant namely his wife does all the research, descriptions, tags and responds to any comments on flickr page.
Birds
Birds (class Aves) are winged, bipedal, endothermic (warm-blooded), egg-laying, vertebrate animals. There are around 10,000 living species, making them the most varied of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from the 5 cm (2 in) Bee Hummingbird to the 2.75 m (9 ft) Ostrich. The fossil record indicates that birds evolved from theropod dinosaurs during the Jurassic period, around 150-200 Ma (million years ago), and the earliest known bird is the Late Jurassic Archaeopteryx, c 150-145 Ma. Most paleontologists regard birds as the only clade of dinosaurs to have survived the Cretaceous-Tertiary extinction event approximately 65.5 Ma.