A groundbreaking discovery regarding the creation of the world’s largest seed, the Coco de Mer coconut, dubbed the “treasure of Seychelles,” has been made by a team of German researchers, inspired by a folk legend from the dreamy island nation of Seychelles.
The Coco de Mer coconut only grows in the Vallée de Mai on Praslin Island (located in the southwestern Indian Ocean). On average, one coconut weighs about 23 to 30 kg, stands between 25 to 34 cm tall, and measures approximately 7 to 10 cm in length.
The island nation of Seychelles, home to the Coco de Mer, is often referred to as the jewel of the Indian Ocean. Located off the eastern coast of Africa, it has intrigued people worldwide, particularly as it was the honeymoon destination for Prince William and Kate Middleton.
Seychelles – The Jewel of the Indian Ocean
The seed of the Coco de Mer coconut is the largest and heaviest seed in the world, believed to have developed from trees submerged in the Indian Ocean. Even after this type of coconut grew on land, locals still believe that for this seed to be produced, the male and female trees must embrace each other during a stormy night.
How can a tree growing in such barren land as this island produce a seed with a diameter of up to half a meter and an average weight of around 25 kg?
New discoveries by scientists focus on how to create the world’s largest seed
The new invention by scientists centers on how to create the world’s largest seed of the Coco de Mer coconut, a treasure of the Republic of Seychelles—often colloquially referred to as “the fruit of the phallus” due to its unusual and distinctive shape.
A team of researchers from Darmstadt University of Technology in Germany analyzed leaves, trunks, flowers, and seed samples taken from the Coco de Mer trees on Praslin Island. The researchers discovered that Coco de Mer leaves contain only about one-third of the nitrogen and phosphorus concentration typically found in the leaves of other trees and shrubs in Seychelles. Additionally, before the older leaves drop, the palm trees withdraw most nutrients from them and recycle these nutrients to support the growth of this largest fruit in the world. Therefore, the nutrients are less concentrated in the leaves and more focused in the palms to nourish the developing coconut.
However, that is not the only way nutrients are supplied to the fruit. The large and arranged leaves effectively channel water down the trunk during rain. Researchers also found that this water carries many nutrients from dead leaves, flowers, pollen, and bird droppings, washing them down to the ground surrounding the base of the tree. As a result, the nitrogen and phosphorus concentrations in the soil 20 cm from the trunk are at least 50% higher than in areas 2 meters away.
This discovery is linked to a remarkable event regarding this palm species: the Coco de Mer appears to be the only palm in the plant kingdom that cares for its seedlings after they germinate. Researchers also found that seedlings benefit from growing in the shadow of their parents, as they can access richer, nutrient-dense soil there.
This new discovery also hypothesizes why the seeds of this coconut are so large.
However, this still does not explain why the seeds of the tree are so large. According to one hypothesis, researchers must look back to the time of the dinosaurs’ extinction. About 66 million years ago, the ancestral forms of this palm may have relied on animals to disperse their relatively large seeds—but this mechanism was later lost when pieces of continental crust broke off, including Seychelles, and formed the Indian subcontinent, isolating this palm species.
This means that seedlings had to adapt to grow in the shadow of their parent trees. Since the large seeds contain a good supply of nutrients, the seedlings were provided with this rich nutrient source, ultimately outcompeting most other plant species in the ecosystem. Even to this day, the Coco de Mer remains the dominant species in the forests where they thrive.
When a forest is dominated by a single species, competition shifts from interspecies rivalry to competition among siblings of the same species. This means that Coco de Mer palms gradually develop larger seeds by providing their offspring with a rich reserve of nutrients, enhancing their chances of survival compared to their siblings.
Nevertheless, the Coco de Mer palm still holds many mysteries yet to be solved, such as how its flowers, the largest in the world, are pollinated. The folk legend of the male tree uprooting itself to embrace the female tree during a stormy night to produce the seeds only adds to the allure of this mystery.
