The Igbo told folktales to explain naturally occurring things in nature like why tortoise's shells are patterned and why vultures are scavengers.
The birds were invited to a feat in the sky and when tortoise saw the preparations he knew exactly what it meant. As soon as he heard of the feast he started planning how he would get to the sky. He sweet talked the birds to let him go and they each gave him a feather to make two wings. He flew among the birds and was chosen to speak for the group. He tricked the birds into taking on new names and tortoise was called "all of you." When they arrived the hosts immediately placed him as the king of the birds. When the hosts informed their guests that the feast was prepared for "all of you," he informed the birds that they would be served after he had eaten. The birds were furious and took back each of their feathers as they flew home, leaving tortoise behind. Parrot agreed to take a message to his wife but told the opposite of what he was told. When tortoise jumped from the clouds he landed every hard surface he owned, cracking his shell. When it was put back together, it created the pattern found on the shells of tortoises.
There was also a story about a fight between the earth and sky. Sky withheld rain fir 7 years and the crops died and the earth was too dry to dig into. Vuture was sent to bargain with Sky and used a song to soften Sky's heart. At last Vulture was given rain in coco-yam leaves. When Vulture flew home he pierced the leaves and the rain fell over the land. He spied a fire in a distant land and ate the entrails he found there left over from a sacrifice.