• 
  Sean Astin

   Narrator / ... (14 episodes, 2007)
• 
  Stockard Channing

   Herself - Narrator (13 episodes, 2008)
• 
  Bill Nighy

   Narrator (26 episodes, 2005-2006)
• 
  Flower the Meerkat

   Herself (30 episodes, 2005-2007)
• 
  Mozart the Meerkat

   Herself (27 episodes, 2005-2007)
• 
  Zaphod the Meerkat

   Himself (22 episodes, 2005-2007)
• 
  Youssarian the Meerkat

   Himself (17 episodes, 2005-2007)
• 
  Mitch the Meerkat

   Himself (17 episodes, 2005-2007)

• 
  Tosca the Meerkat

  Self
• 
  Shakespeare the Meerkat

  Self
• 
  Rocket Dog the Meerkat

  Self
• 
  Houdini the Meerkat

  Self
• 
  Maybelline The Meerkat

  Self
• 
  Reg E. Cathey

  Narrator
• 
  Dave Bell

  Self - Researcher

• 
  Zanna Clay

  Self - Researcher
• 
  Tim Clutton-Brock

  Self - Scientific Consultant: Cambridge University
• 
  Julian Drewe

  Self - Veterinarian
• 
  Caroline Hawkins

  Self - Creator and Series Editor
• 
  Robin Smith

  Self - Cinematographer
• 
  Rebecca Rose

  Self - Senior Researcher
• 
  Thomas Flower

  Self - Field Project Manager