Bird anatomy Birds have a four-chambered heart, in common with mammals, and some reptiles (mainly the crocodilia). This adaptation allows for an efficient nutrient and oxygen transport throughout the body, providing birds with energy to fly and maintain high levels of activity. A ruby-throated hummingbird's heart beats up to 1200 times per minute (about 20 beats per second). Many birds possess a muscular pouch along the esophagus called a crop. The crop functions to both soften food and regulate its flow through the system by storing it temporarily. The size and shape of the crop is quite variable among the birds. Members
The Birds of Australia (Gould) of Australia" in the two-volume "Handbook to the Birds of Australia". The Birds of Australia (Gould) The Birds of Australia was a book written by John Gould and published in seven volumes between 1840 and 1848. It was the first comprehensive survey of the birds of Australia and included descriptions of 681 species, 328 of which were new to science and were first described by Gould. Gould and his wife Elizabeth travelled to Australia from England in 1838 to prepare the book. They spent a little under two years collecting specimens for the book. John travelled widely and made extensive