page_title: Leucospermum
section_title: Seed dispersal
hierarchical_section_title: Leucospermum / Ecology / Seed dispersal
caption_attribution_description: Leucospermum glabrum, seed head
context_page_description: Leucospermum is a genus of evergreen upright, sometimes creeping shrubs that is assigned to the Proteaceae, with currently forty-eight known species. Almost all species are easily recognised as Leucospermum because of the long protruding styles with a thickened pollen-presenter, which jointly give the flower head the appearance of a pincushion, its common name. Pincushions can be found in South Africa, Swaziland, Zimbabwe and Mozambique.
  The shrubs mostly have a single stem at their base, but some species sprout from an underground rootstock, from which the plant can regrow after fire has killed the above ground biomass. In a larger group of species, specimens are killed by fire, and their survival depends on the seeds. In all species, seeds are collected by ants, which take them to their underground nests to feed on their ant breads, a seed dispersal strategy known as myrmecochory. This ensures that the seeds do not burn, so new plants can grow from them.
context_section_description: The fruits of Leucadendron have but one seed cavity, that does not open, and contains only one seed, a fruit type called nut. The fruits consist partly of a whitish, fleshy or gelatinous pericarp, a so-called elaiosome, that attracts ants because they contain chemicals that mimic pheromones. After the fruits fall from the plant, mostly Anoplolepis ants gather them, and carry them to their nest by sinking their jaws in the fleshy elaiosome. Ones in the underground nests, the elaiosome is consumed. The smooth and hard seeds that remain do not fit the ants' small jaws, and are abandoned, protected from fire and seed eaters. The survival of the seeds is further enhanced by fungicidal and anti-bacterial substances that the ants excrete to keep their nests in a healthy condition. In the fynbos, this so-called myrmecochory is a strategy used by many plant species to survive the fire. Invasive ants species, like in South Africa Linepithema humile (Argentine ant), destroy the nests of the indigenous ants, and eat the elaiosomes where ever the seed has fallen, so that it is not protected against fire and can easily be found and eaten by mice and birds.
caption: Seedhead of Leucospermum glabrum
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