(Image credit: Ken Thorne)

Posted by Ellen

Among the finalists for this year's National Geographic photo competition is this shot of a baobab grove near the town of Morondava in western Madagascar. 

Baobabs are unusual trees, with swollen trunks that store water, allowing them to survive long periods of drought. Some species of baobab can grow without soil, drilling their roots directly into bare limestone, and some are so tolerant of salt water they can grow within a few feet of the ocean. 

The trees in this picture are believed to be many thousands of years old, but baobab wood does not produce annual growth rings, making age calculations rather speculative. 

Baobabs produce fruit with a flavor that is described as very tart and grapefruit-like. The fruit pulp is a common ingredient in many regional dishes and is being studied by international food companies as a possible additive to Western-style foods and beverages, such as fruit smoothies. "It brings an interesting and exotic flavor," said PhytoTrade spokesperson Lucy Welford. "Now that we've had a lot of interest in Europe, I think there might be a knock-on effect in the U.S."