Why is the Amniotic Egg Considered an Important Evolutionary Breakthrough

Question

Why is the amniotic egg considered an important evolutionary breakthrough?
A) It has a shell that increases gas exchange.
B) It allows deposition of eggs in a terrestrial environment.
C) It prolongs embryonic development.
D) It provides insulation to conserve heat.
E) It permits internal fertilization to be replaced by external fertilization.

Accepted Answer

The amniotic egg allowed for the deposition of eggs in a terrestrial environment, which was a critical evolutionary development for many species to transition from aquatic to terrestrial lifestyles.

Answer: A, D
 The amniotic egg also had a shell that increased gas exchange and provided insulation to conserve heat, which were both important adaptations for survival in a terrestrial environment.

Answer: C and E are incorrect because prolonging embryonic development and replacing internal fertilization with external fertilization are not unique features of the amniotic egg.