Series 3 Episode 5
First Broadcast: 7PM Fri 25 December 2009

Professor Hartley asks what has gone wrong when herbivores get the upper hand and strip plants bare.

Sometimes 'outbreaks' of herbivores devastate our forests and crops: why do plant defences fail? Will climate change compromise the abilities of plants, including our crops, to defend themselves? Will pest outbreaks become more common in the future as plant defences weaken? Will alien species invade?

Professor Hartley explores whether climate change will upset the balance in the arms race between plants and herbivores. Will global food production be threatened by new pests and diseases and what we can do about these threats? What are the weapons of the future as we try and protect the world's food supply and its natural resources against climate change?

Whatever the future holds, the 300-million-year war between plants and animals is certain to continue.

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    1. Series 3 Episode 5 The Royal Institution Christmas Lectures

      Professor Hartley asks what has gone wrong when herbivores get the upper hand and strip plants bare.

    2. Series 3 Episode 4 The Royal Institution Christmas Lectures

      Professor Hartley asks if humans are natural herbivores. How good are we at eating plants and overcoming their defences?

      clips
      1. Cup of Poison This video is a clip Cup of Poison Video duration: 1:57 minutes

        It tastes lovely but did you know that coffee is a poison?
      2. Dangerous but Delicious This video is a clip Dangerous but Delicious Video duration: 2:05 minutes

        All children love a bit of chocolate poison...
    3. Series 3 Episode 3 The Royal Institution Christmas Lectures

      Professor Hartley asks if talking trees are science fiction or reality.

      clips
      1. Talking Plants This video is a clip Talking Plants Video duration: 2:55 minutes

        Sue Hartley simulates plant communications with the audience.
    4. Series 3 Episode 2 The Royal Institution Christmas Lectures

      The life of a herbivore is not a happy one. For a start, plants are the wrong sort of food for animals: they are low in…

      clips
      1. Fast Phloem This video is a clip Fast Phloem Video duration: 2:00 minutes

        A high pressure aphid eating demonstration
      2. Herbivore Hazards This video is a clip Herbivore Hazards Video duration: 2:12 minutes

        Comparing the nutritional differences between herbivores and carnivores
    5. Series 3 Episode 1 The Royal Institution Christmas Lectures

      Professor Hartley reveals how, despite animals' attempts to destroy plants by eating them, plants are winning the war.

      clips
      1. Inspiring Science This video is a clip Inspiring Science Video duration: 1:49 minutes

        Baroness Greenfield introduces the 2009 Christmas Lectures
      2. Holly and Clemie at war This video is a clip Holly and Clemie at war Video duration: 1:58 minutes

        Professor Sue Hartley demonstrates the ptotective surface of leaves
    1. Holly and Clemie at war This video is a clip Holly and Clemie at war Video duration: 1:58 minutes

      Professor Sue Hartley demonstrates the ptotective surface of leaves Watch The Royal Institution Christmas Lectures Series 3 Episode 1
    2. Inspiring Science This video is a clip Inspiring Science Video duration: 1:49 minutes

      Baroness Greenfield introduces the 2009 Christmas Lectures Watch The Royal Institution Christmas Lectures Series 3 Episode 1
    3. Fast Phloem This video is a clip Fast Phloem Video duration: 2:00 minutes

      A high pressure aphid eating demonstration Watch The Royal Institution Christmas Lectures Series 3 Episode 2
    4. Herbivore Hazards This video is a clip Herbivore Hazards Video duration: 2:12 minutes

      Comparing the nutritional differences between herbivores and carnivores Watch The Royal Institution Christmas Lectures Series 3 Episode 2
    5. Talking Plants This video is a clip Talking Plants Video duration: 2:55 minutes

      Sue Hartley simulates plant communications with the audience. Watch The Royal Institution Christmas Lectures Series 3 Episode 3
    6. Cup of Poison This video is a clip Cup of Poison Video duration: 1:57 minutes

      It tastes lovely but did you know that coffee is a poison? Watch The Royal Institution Christmas Lectures Series 3 Episode 4
    7. Dangerous but Delicious This video is a clip Dangerous but Delicious Video duration: 2:05 minutes

      All children love a bit of chocolate poison... Watch The Royal Institution Christmas Lectures Series 3 Episode 4

The Royal Institution Christmas Lectures on Channel4.com

See more about The Royal Institution Christmas Lectures

The Royal Institution Christmas Lectures have been inspiring children and adults alike since 1825, with the express purpose of teaching science to young people