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Why Do We Talk?

Talking is a phenomenon that is unique to humans, yet it remains a mystery. Horizon meets the people unlocking the secrets of speech and looks at the theories of linguistics.

Talking is something that is unique to humans, yet it still remains a mystery. Horizon meets the scientists beginning to unlock the secrets of speech - including a father who is filming every second of his son's first three years in order to discover how we learn to talk, the autistic savant who can speak more than 20 languages, and the first scientist to identify a gene that makes speech possible.

Horizon also hears from the godfather of linguistics, Noam Chomsky, the first to suggest that our ability to talk is innate. A unique experiment shows how a new alien language can emerge in just one afternoon, in a bid to understand where language comes from and why it is the way it is.

1 hour


Timings (where shown) are from the start of the programme in hours and minutes

  • Why do we talk?: Introduction

    How and why do we use language and speech?

    Duration: 03:16

  • How do children learn to speak?

    Dr Deb Roy has used cameras and microphones to record all his son's noises and speech from birth until he was three years old, so he can understand how we learn to talk.

    Duration: 06:10

  • Why can't animals talk?

    Humans are the only species that can talk extensively; not even our closest relative, the chimp, can speak. But why is this?

    Duration: 05:41

  • How does the brain work with regards to speech?

    Steve Steere was involved in an accident which left him unable to speak properly. Now, Steve undergoes testing to see what parts of the brain are involved in speech development and usage.

    Duration: 08:58

  • When does a brain switch on to language?

    A look at how and when babies start to respond to the speech and language around them.

    Duration: 04:00

  • Why is it difficult to learn a language as an adult?

    Christopher Taylor is autistic and can speak over 20 languages. This also means he can learn words in new languages at an exceptional rate.

    Duration: 04:10

  • Could we develop language on our own?

    It is unethical to isloate a child and raise it in silence to see if they would develop speech on their own. However, one scientist has got around this, by using birds.

    Duration: 09:14

  • How do we speak?

    It appears that language is built into our genes, but unpicking the component of language is a huge challenge.

    Duration: 06:12

  • Why do we actually talk?

    An insight into why humans came to speak and how they came about creating language.

    Duration: 07:51

  • Final Summary

    Language and speech will change from generation to generation, with many different aspects effecting its development.

    Duration: 04:00


Role Contributor
Director Damon Thomas
Producer Penny Palmer
Executive Producer Andrew Cohen


  • Tue 10 Nov 2009 21:00
  • Tue 10 Nov 2009 22:30
  • Tue 15 Dec 2009 03:00