Where did the coconut originate?

The origin of the coconut (Cocos nucifera) is subject to controversy. Now, the coconut palm has a worldwide distribution, though its presence is limited to the tropics. But that very distribution makes it difficult to pinpoint its original home. So, where did the coconut originate?

In his 1901 book ‘The Origins and Distribution of the Cocoa Palm’ the American biologist O. F. Cook tried to prove that the coconut palm originated from South America. His theories were based more on conjecture than on sound science. He claimed that ‘… evidence of the existence of the banana in prehistoric America is equal, if not superior to that here presented for the cocoanut.’ Sure, that might be true, but it surely proves nothing. Others have tried to prove that the species originated in the Indian Ocean.
Even now, proponents of a South American origin fail to explain why it is not indigenous there and why it shows greatest diversity in southern Asia. On the other hand, proponents of an Asian origin must explain why there are no Asian Cocoseae and why the closest botanical relative to Cocos is in South America.

Both hypotheses share the common problems of how, when, where and in what directions long-distance dispersal occurred. These difficulties are resolved[1]  by accepting that the coconut originated and dispersed by populating emerging islands of the coral atoll ecosystem in the Pacific Ocean.

Driven by currents, the coconuts can drift long distances, and when lifted by wave action onto virtually sterile, soilless coralline rocks just above sea level and exposed to the sun, the nuts will quickly germinate, root and establish themselves in large populations. But currents alone cannot explain the entire pattern of dispersal of the coconut palm but that is consistent with human introductions of Pacific coconuts along the ancient Austronesian trade routes connecting Madagascar to Southeast Asia[2].

Therefore, the evidence supports a theory of a Pacific origin of the coconut palm.

[1] Harries et al: Long-distance dispersal of the coconut palm by migration within the coral atoll ecosystem in Annals of Botany - 2014
[2] Gunn et al: Independent origins of cultivated coconut (Cocos nucifera L.) in the old world tropics in PLoS One - 2011

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