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
War of the Birds even in the film at which Fagin scratched his slave and when Betty ripped out Fagin's eye and at Armstrong's party was sexual content. About 30 seconds of the film was cut for the U.S. release. War of the Birds War of the Birds () is a Danish animated movie directed by Jannik Hastrup in 1990, about two orphan birds, Oliver and Olivia, who fight against an evil vulture with the help of two mice. It is based on a children's book of the same name from Bent Haller. In a forest lives a community of birds who live peacefully,