The only description of the dodo’s diet dates back to 1631. It is placed in a Dutch letter, which was long thought to be lost, but was found in 2017. The letter reveals that the birds fed on fallen fruit, possibly also nuts, seeds, bulbs, and roots. It has also been suggested that they may have eaten crabs and crustaceans.
Their favorite food was likely the seeds of the Sideroxylon grandiflorum tree, also known as the tambalacoque tree or dodo tree. This is a long-lived tree species in the family Saporaceae, endemic to Mauritius. It was claimed that the dodo ate the fruit of the tambalacoque, and that seeds passing through its digestive tract gained the ability to germinate. With the extinction of the dodo, the trees also began to die out. Scientific research has not confirmed the theory of a relationship between the extinction of trees and the dodo bird.
