Unashamedly stolen from factor-fiction's link because it is so interesting.
Many people like to grow mangoes from seed as a fun project. The seeds readily sprout and grow vigorously, much to the delight of the people who planted them. The problem is that mango trees, produced through sexual reproduction, usually grow the most horrid tasting fruit. These seedling trees are really only good for one thing, as a rootstock for grafting a desirable mango varietal onto. *note:Many mango trees produce polyembryonic seeds. These seeds contain many baby trees in one seed. Some of them are clones of the mother tree, and some are the result of sexual reproduction. There is a chance, when growing these types of seeds, that the resulting tree will be a clone of the mother.