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David 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.
First Air Date : Jan 29, 2013
Last Air date : Jun 25, 2017
Episode : 27 Episode
Season : 4 Season
Runtime: 22:14 minutes
Country:
Cast: David Attenborough
Crew: