Notre part animale - Season 1 Episode 3

Horizon tells amazing science stories, unravels mysteries and reveals worlds you've never seen before.

Dr Helen Czerski examines the world of sound waves.

Carl Sagan covers a wide range of scientific subjects, including the origin of life and a perspective of our place in the universe.

Andrew Marr explores how Darwin's theory of evolution by natural selection has taken on a life of its own far beyond the world of science.

Hannah Fry takes a spectacular look at the science of size by imagining a parallel world in which everything is made bigger or smaller.

Survival instructor Marc Mouret have 100 days to sharpen his body and mind to take on extraordinary challenges.