Digestion a thin-walled expanded portion of the alimentary tract used for the storage of food prior to digestion. In some birds it is an expanded, muscular pouch near the gullet or throat. In adult doves and pigeons, the crop can produce crop milk to feed newly hatched birds. Certain insects may have a crop or enlarged esophagus. Herbivores have evolved cecums (or an abomasum in the case of ruminants). Ruminants have a fore-stomach with four chambers. These are the rumen, reticulum, omasum, and abomasum. In the first two chambers, the rumen and the reticulum, the food is mixed with saliva and
Handbook of the Birds of the World year 1500. Handbook of the Birds of the World The Handbook of the Birds of the World (HBW) is a multi-volume series produced by the Spanish publishing house Lynx Edicions in partnership with BirdLife International. It is the first handbook to cover every known living species of bird. The series is edited by Josep del Hoyo, Andrew Elliott, Jordi Sargatal and David A. Christie. All 16 volumes have been published. For the first time an animal class will have all the species illustrated and treated in detail in a single work. This has not been done before for any other