TV
David Attenborough's Natural Curiosities
Season 4 Episode 5: Incredible Shells
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.
- Genre:
- Documentary
- Seasons:
- 4
- Episodes:
- 27
- Cast:
- David Attenborough
- Quality:
- HD
- Duration:
- 30 min
- First Air:
- 2013
- Rating:
- 7.3









