Amphibian
Tadpoles do not have lungs when they hatch and instead have gills. Because gills have a large surface area, tadpoles can get more oxygen by using them. Young tadpoles have their gills exposed. When they get older, their gills are covered over by skin.p6  When they hatch, tadpoles eat constantly. The tadpoles eat what is left of their eggs, this is usually their first food.p8