There was a time when Tortoise had a shiny shell and was very speedy...

He loved to race around and show off! When he discovers that the Birds are having a Feast in the Heavens, cunning Tortoise persuades the Birds to make him some wings and he races up through the clouds leaving the Birds far behind. When he arrives at the Feast, Tortoise eats the lot! Angry, the Birds pluck off his feathers and he falls from the skies and lands on his shell breaking it into hundreds of pieces. Although the animals piece Tortoise's shell back together, he will never move speedily again.