What is a Pouchlike expanded part of oesophagus birds?

The crop is the pouchlike expanded part of the oesophagus of birds. It serves as a temporary storage site for food, allowing birds to accumulate food before digesting it. The crop is particularly well-developed in granivorous birds, which feed on seeds, and herbivorous birds, which consume large quantities of plant matter. The food stored in the crop is moistened and softened by secretions produced by the crop glands, facilitating its digestion. When the bird is ready to digest the food, it passes from the crop into the stomach for further processing. The presence of the crop enables birds to feed quickly and efficiently, especially when food is abundant, and it plays an essential role in their digestive physiology and survival.