This is correlated with the pronounced lateral flexion of the spine that is needed for axial locomotion. In these vertebrates, locomotion is primarily appendicular, which does not require lateral flexion of the spine. These tissues function to support and connect the submucosa layer to surrounding layers, to innervate the muscle fibers of the mucosa and muscularis externa, to supply oxygen and nutrients, and to take up and transport nutrients away from the gut. There are two different mechanisms by which scapular rotation increases running speed. Briefly explain each of them.
Scapular rotation allows greater extension of the forelimbs during each stride cycle.
This increases stride length. This increases stride frequency. Briefly describe a specialized function performed by the crop serve in a particular bird or group of birds. The crop is primarily a storage area for food in most birds, holding food awaiting entry to the stomach near the center of gravity of the body. The size of the crop is dependent on the amount of food ingested at one time, and how slowly it is digested.