Why do most amphibians lay their eggs in water?
Most of the amphibians lay eggs in water because the eggs produced do not have amnion which makes the eggs receptive to heat and dryness. So on laying in water, they can prevent this dryness. Also, amphibian eggs do not have a hard protective shell like bird or reptile eggs. Most amphibian eggs become much bigger after they are laid because the eggs absorb water and swell to several times their original volume by diffusion.
