5 Temporada
100 Episodio
Bill el Científico - Season 3 Episode 18 Episodio 18
Scientists believe that birds evolved from reptiles. Birds have backbones, and they lay eggs, but they’ve developed a unique feature that sets them apart from all other animals – feathers. Feathers are made of the same stuff human fingernails and hair are made from – a protein called keratin. Feathers, combined with lightweight bones, powerful wings and strong hearts let birds fly.
- Año: 1998
- País: United States of America
- Género: Comedy, Documentary, Kids
- Estudio: PBS
- Palabra clave: technology, space, educational, science
- Director: Bill Nye
- Emitir: Bill Nye, Rachel Glenn, Jennifer Lin, Amy Broder, Ethan Ferkiss