Memphis Zoo FAQs Zoo visitors ask some very interesting questions . . . Butterflies The monarch butterfly. Birds Veins and arteries in the feet of penguins lie very close to each other and in some cases are actually intertwined. The warm arterial blood from the heart loses some heat to the cool venous blood from the feet, maintaining a regular temperature.
Birds preen to clean their feathers and to repair and realign loosened feather barbules.
Oil from the preen gland turns to vitamin D when exposed to sunlight. This may be ingested by the bird or absorbed through the skin. No, but any rat, squirrel or pigeon that ventures into their flight cage does so at its own risk. They have been clocked in gliding and flapping flight between 36-44 mph. This evidently helps to suppress the other females' sexual development.