Biology, ecology, and evolution of coconut

Abstract

The coconut fruit comprises the nut enclosed in a thick husk. When germination takes place, there is a delay of 20 days or more until the young shoot and roots emerge through the husk. At first the shoot produces a tiny frond followed by those of increasing size every 6 weeks, reducing to 4 weeks over time. There is a sequential increase in frond length up to a maximum around 5 years when flowering begins. The frond survives for 2 years so that the palm carries up to 30 fronds in a hemispherical array. There are two forms of palm, Tall and Dwarf. The Dwarf forms flowers earlier and remains shorter than the Tall at any age. The inflorescence comprises both male and female flowers. The Tall is normally cross-pollinating resulting in a heterozygous population, while the Dwarf is mostly self-pollinating resulting in homozygous progeny. There is no natural formation of suckers or other vegetative reproduction. The coconut fruit evolved being capable of floating for 120 days on the ocean and then establishing on the strand of tropical atolls and the coastlines of high islands with adequate rainfall. The coconut appears to have spread widely to many suitable shores between the east coast of Africa and the west coast of the Americas long before human settlement. There is evidence of evolutionary adaptation of the coconut to diverse biohazards in different tropical regions. For example, insect, virus, and mycoplasma tolerances have been described.