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
Birds of the Amazon roads and logging deters birds and other animals from living in those sections of the forest. It can be observed that there is a lot less bird movement near areas with roads and lodging than those without. Understory species are especially vulnerable to effects of road clearing. Even roads that are narrow with less traffic can have a significant impact on the movements of insectivorous birds in the Amazon. Birds of the Amazon An immense number of bird species live in the Amazon rainforest and river basin (an area which is nominally home to one out of every ten known