7.30/10 2017-06-25 48 의사록.HDDavid Attenborough investigates two shells that have proved to be winners in evolution: the bird’s shell and the hard shell of the tortoise. The ostrich egg is so strong it’s possible for a person to stand on it without it breaking – how does the chick break out of this fortress? The evolution of the tortoise shell was for a long time a mystery and this bony box offers a lot more than just protection.년: 2017사진관: Eden, U&W국가: