Fruits, the mature ovaries of flowering plants, encase and protect seeds, which are the reproductive units capable of developing into new plants. They exhibit a wide range of sizes, from tiny specks to massive objects. This diversity highlights plants’ varied evolutionary strategies for survival and propagation.
The Coco de Mer: World’s Largest Seed
The world’s largest seed belongs to the coco de mer, scientifically known as Lodoicea maldivica. This palm is endemic to just two islands in the Seychelles: Praslin and Curieuse. Its seeds are colossal, weighing up to 25 kilograms (55 pounds) and measuring up to 50 centimeters (nearly 20 inches) in length. Its distinctive, double-lobed shape often resembles a woman’s pelvis, earning it nicknames like “love nut” or “coco fesse.”
Before its origin was discovered, these massive seeds washed ashore in distant lands like the Maldives, leading to myths of them growing on mythical underwater trees. The palm is slow-growing, taking 25 to 50 years to mature and flower, with fruits taking six to seven years to fully develop. Its rarity and unique appearance have made it a prized collector’s item and a symbol of Seychelles’ heritage. Despite its large size, the mature coco de mer seed does not float when it first falls, only becoming buoyant after its internal contents decay over time.
The Biology Behind Seed Size
Seed size in plants results from biological trade-offs and adaptations to environmental conditions. Larger seeds contain more stored nutrients, providing a greater energy reserve for the germinating seedling. This nutritional endowment can increase the seedling’s survival, particularly in stressful environments like shade or drought. Conversely, plants producing many small seeds have an advantage in favorable conditions, dispersing more propagules and increasing the likelihood of finding suitable growth sites.
Dispersal strategy also influences seed size. Plants have evolved mechanisms to spread seeds away from the parent plant, reducing competition and promoting colonization. Large seeds, like the coco de mer, often use hydrochory (water dispersal), though the coco de mer’s initial sinking limits its natural range. Other large seeds might be dispersed by gravity, simply falling from the parent plant. Smaller seeds can be carried by wind (anemochory) or animals (zoochoory), either by consumption and excretion, or by attaching to fur or feathers.
Other Fruits with Prominent Seeds
Beyond the coco de mer, many other fruits have substantial or distinctive seeds.
The avocado, a popular fruit, contains a single large seed, often called a pit or stone, which can make up 13% to 17% of the fruit’s weight. Though commonly discarded, avocado seeds contain compounds like antioxidants, fiber, and healthy fats; their safety for consumption is still under investigation.
Mangoes also feature a flattened, often fibrous seed at their core, containing nutrients like protein, healthy fats, and antioxidants. These seeds can be used in traditional medicine or as a source of oil.
Peaches, a type of stone fruit, have a hard, furrowed pit enclosing their seed. This pit protects the seed, which can grow new peach trees.
Dates, small sweet fruits, contain an oblong, hard-coated seed that typically makes up 6% to 20% of the fruit’s weight. Date seeds have been used as animal feed and can be processed into a powder or oil.
The jackfruit, a large tropical fruit, also houses numerous seeds. These seeds are edible when cooked and are rich in starch, protein, vitamins, and minerals.