The wild olive tree present in the countries along the Mediterranean is a thorny bush producing small fruit, with a big pit and little pulp, unlike the cultivated varieties which have no thorns and producing a fleshy fruit rich in oil.
Probably the wild olive tree is not a true forefather of the cultivated tree, even though the two of them have very similar genetic and chromosome characteristics. It is possible to assume that the cultivated olive tree originates from a hybrid of two different varieties: from one of them, maybe the "Olea Africana", it might have inherited the oblong leaf, and from the other, unknown, the fleshy fruit with a large quantity of oil.

 The deep differences between wild and cultivated varieties are due to the work of men, who for thousands of years have conserved, cultivated and selected olive trees, deeply changing their characteristics. Almost 6,000 years ago, during the Bronze Age, the communities of farmers living on the coast of the eastern Mediterranean, nowadays the coasts of Syria and Palestine, tended a population of olive trees with large fruit, and started to select the varieties in a systematic way. They found out that it was possible to extract, with some effort, a dense, oily liquid, easy to burn and good for the skin, with a pleasant aromatic taste. 
The study of the long process of domestication is very complex, because it is not always possible to differentiate, by examination of the vegetal residue (wood, pollens and, to a certain extent, pits) the cultivated varieties from the wild ones.
Pits of wild and cultivated olive trees 
The photograph points out the differences between pits of cultivated and wild trees, above all with reference to size (up to 1O mm (0.4in) in wild trees, more than that in the cultivated ones).

In the past the creation of the olive tree was ascribed to heroes and gods, and was considered a precious gift to mankind; for thousands of years many legends have made reference to the role played by Osiris, Athena, Aristaeus, Heracles and many others. It can be affirmed that every great Mediterranean civilization worked out its own myth to explain the origin of the first cultivated olive tree.