Genetics and the origin of bird species - PMC In the last 25 years several field studies have documented by observation the occurrence of hybridization of bird species and shown that hybrids are viable and fertile to a large degree (19, 54) For example, at least half of 29 sympatric species pairs of North American birds hybridize, and at least a quarter backcross frequently
Ch. 8 Flashcards - Quizlet Study with Quizlet and memorize flashcards containing terms like The introduction of ________ onto the island of Guam has resulted in the extinction of most of the endemic forest bird species on the island , Paleontologists estimate that ________ , How is community-based conservation different from more traditional approaches to conservation? and more
Impact of Urbanization on Birds - SpringerLink Among the over 10,000 recognized bird species in the world, around 2000 (nearly 20%) occur in cities (Aronson et al 2014) Although some bird species are cosmopolitan and thus occur in cities across the globe (e g , Feral Pigeon Columba livia, House Sparrow Passer domesticus, Common Starling Sturnus vulgaris, Barn Swallow Hirundo rustica; Aronson et al 2014), most urban species are
‘One of a kind’ fossil from the age of dinosaurs reveals . . . The 80-million-year-old complete skull of a bird is revealing more about the evolution of brain structure from the earliest known bird-like dinosaurs to modern birds A ‘one of a kind’ discovery could help solve one of the most enduring mysteries of vertebrate evolution – how birds developed their unique intelligence
Swarm behaviour - Wikipedia Approximately 1800 of the world's 10,000 bird species are long-distance migrants [102] The primary motivation for migration appears to be food; for example, some hummingbirds choose not to migrate if fed through the winter Also, the longer days of the northern summer provide extended time for breeding birds to feed their young