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Snowball Earth

Tracing the history and evolutionary implications of a controversial theory, which posits that for millions of years the Earth was entirely covered in ice up to a kilometre thick.

There is a controversial theory that for millions of years the Earth was plunged into a catastrophe and entirely smothered in ice, up to one kilometre thick. The temperature hovered around minus 40 C - everywhere, even in the tropics and the equator. If this really happened, then virtually nothing could have survived this ferocious climate. There are some tantalising geological clues that show this theory may be true but the problem is, the clues and the Snowball Earth theory defy the laws of nature.For over fifty years a group of scientists have been trying to prove this incredible period of Earth history. Struggling against scepticism and disbelief, now finally the many mysteries have been solved and the scientific community is slowly coming around to the extraordinary idea not just of the dramatic freeze, but of an equally dramatic thaw.From the baking landscape of Africa to ice-covered Antarctica, Horizon follows the tale of a theory which, if true, would have huge implications. Because scientists now believe this cycle of freezing and frying may have created the unique conditions needed for the evolution of complex life, including our own - and that humans only exist because of the catastrophic events of Snowball Earth.

50 minutes

Last on

Wed 17 May 2006 10:40

Broadcasts

  • Thu 22 Feb 2001 21:00
  • Wed 7 Mar 2001 10:00
  • Wed 7 Mar 2001 13:00
  • Wed 7 Mar 2001 16:00
  • Wed 7 Mar 2001 19:00
  • Wed 7 Mar 2001 22:00
  • Thu 8 Mar 2001 01:00
  • Sun 11 Mar 2001 07:00
  • Sun 11 Mar 2001 11:00
  • Sun 11 Mar 2001 15:00
  • Sun 11 Mar 2001 19:00
  • Sun 11 Mar 2001 23:00
  • Sun 17 Jun 2001 09:30
  • Sun 17 Jun 2001 12:30
  • Sun 17 Jun 2001 15:30
  • Mon 18 Jun 2001 00:00
  • Sun 28 Oct 2001 10:00
  • Sun 28 Oct 2001 13:10
  • Sun 28 Oct 2001 16:00
  • Sun 28 Oct 2001 19:00
  • Mon 29 Oct 2001 00:10
  • Wed 17 May 2006 10:40