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Nature has devised two different strategies for seed production. Some plants release countless numbers of very small seeds and others a smaller number of larger seeds. The former rely on strength in numbers and the odds that at least some will survive to adulthood. The latter invest a lot of energy-producing seeds with a generous food reserve, in the hope it will boost the prospects of each seedling. At more than 1ft (30cm) long and weighing upwards of 3st (18kg), the world’s largest seed is the coco de mer, or sea coconut, produced by the lodoicea palm. Avocados and peaches also have very big seeds. At the other end of the scale are seeds so tiny they look like dust. Orchid seeds are the smallest of any plant, those of the delicate lady’s tresses orchid weighing just 2 micrograms. Every few years, some woodland trees, notably the oak and beech, release huge numbers of seeds. Known as mast years, they occur in an irregular cycle, but are usually between two and five years apart. All the trees in a population synchronise to mass-produce seeds at the same time, upwards of 50,000 acorns falling from a single oak. Although there is no consensus on how or why this happens, many believe the trees are adopting an ‘all or nothing’ approach. All their energy is put into producing so many seeds that predators cannot possibly eat them all. This ensures the survival of such a high number that resources can be channelled into other activities, such as trunk growth, in the intervening years. This strategy works well for the trees, but how they cooperate to achieve it remains a mystery.