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Although caecilians and frogs look structurally different, what are there similarities? How did this come about?
Because the have a common ancestor they both have moist skin, lay eggs, and have a buccal cavity to breathe.
This happened becomes form follows function, since the caecillian is a burrowing creature underground it has become long and slender with a hard, flat skull. Since the frog lives above ground it has to quickly escape predators and catch prey, eventually leading to strong limbs.