Food for Thought

The coconut conundrum. 
Tropical coconut palms (Cocos nucifera) flourish on shorelines in a worldwide band 25 degrees north and 25 degrees south of the equator. It’s considered the tree of life in many cultures, and is certainly top contender for gold when it comes to “world’s most useful plants”. With each tree yielding thousands of coconuts over a 60–80-year lifespan, it provides, in one neat package, a high-calorie food, potable water, fiber that can be spun into rope, and a hard shell that can be turned into charcoal. What’s more it makes a handy flotation device if you need it. And it’s not a nut, it is a drupe or stone fruit.

But where did it come from originally? Check out your plant guide and you’ll find there’s some disagreement about origins. “The traditional argument” says plant evolutionary biologist Kenneth Olsen “was that the niu kafa (triangular and oblong with a large fibrous husk) form was the wild, ancestral form that didn’t reflect human selection, in part because it was better adapted to ocean dispersal”. Dwarf trees with the rounded niu vai fruits that contain abundant sweet coconut water when unripe were thought to be the domesticated form that arose only in the Pacific. (Niu kafa and niu vai are Samoan names for traditional Polynesian varieties.) “The lack of universal domestication traits together with the long history of human interaction with coconuts, made it difficult to trace the coconut’s cultivation origins strictly by morphology (form and structure),” Olsen says. DNA was a different story.

When he and colleagues examined the DNA of more than 1300 coconuts from all over the world they report in PlosOne that Pacific and Indian Ocean coconuts are quite distinct genetically. In the Pacific, coconuts were likely first cultivated in island Southeast Asia (Philippines, Malaysia, Indonesia), and perhaps the continent as well. In the Indian Ocean the likely center of cultivation was the southern periphery of India, including Sri Lanka, the Maldives, and the Laccadives (Lakshadweep).

One exception to the general Pacific/Indian Ocean split is the western Indian Ocean, specifically Madagascar and the Comoros Islands. The coconuts here are a genetic mixture of both Indian and Pacific oceans types. They believe the Pacific coconuts were introduced to the Indian Ocean a couple of thousand years ago by Austronesians establishing trade routes connecting Southeast Asia to Madagascar and coastal east Africa.

Much later the Indian Ocean coconut was transported to the New World by Europeans. The Portuguese carried coconuts from the Indian Ocean to the West Coast of Africa, Olsen says, and the plantations established there were a source of material that made it into the Caribbean and also to coastal Brazil.

So the coconuts that you find today in Florida are largely the Indian ocean type, Olsen says, which is why they tend to have the niu kafa (triangular) form. On the Pacific side of the New World tropics, however, the coconuts are Pacific Ocean coconuts. Some appear to have been transported there in pre-Columbian times by ancient Austronesians moving east rather than west. In addition, the Spanish brought coconuts to the Pacific coast of Mexico from the Philippines, which was for a time governed on behalf of the King of Spain from Mexico.This is why, Olsen says, you find Pacific type coconuts on the Pacific coast of Central America and Indian type coconuts on the Atlantic coast. (Source: Eurekalert.)