As inhabitants of both land and water, amphibians have a universal respiratory system. That number is, sadly, dropping quickly because amphibians are so vulnerable to pollution. Smooth sided Toad Toad, Animals Some axolotl salamanders keep their gills throughout life.Young amphibians breathe with. Reptile and bird embryos have membranes on the inside of the shell which are rich in blood vessels (these are the blood vessels one can see when ‘candling’ an egg). Amphibians are ectothermic, tetrapod vertebrates of the class amphibia.all living amphibians