Besides feeding on their regular food like grains and other types of various seeds, birds also feed on grit. Nature's reason behind birds feeding on grit is to provide a substance to the birds that will help them digest whatever food they intake. Having no teeth, the process of chewing is accomplished in the birds by the gizzard. As the process of chewing requires strong muscles and jaw bones, which the birds don't have. This is because the delicacy of the birds' structure allows the skull to be light and dainty in structure to harmonize with the rest of the skeleton, being light in weight too.
Gizzard, which is also known as ventriculus, intakes the grit. The thick and mostly muscular walls of the gizzard along with the joint action by the two walls grinds down the hard grit. The gizzard is the back part of a bird's stomach. The front part of the stomach is glandular and secretes out digestive juices and is called proventriculus.
Gizzard, which is also known as ventriculus, intakes the grit. The thick and mostly muscular walls of the gizzard along with the joint action by the two walls grinds down the hard grit. The gizzard is the back part of a bird's stomach. The front part of the stomach is glandular and secretes out digestive juices and is called proventriculus.