The elongated tip (or, in botanical terms, an exaggerated acumen) of a leaf found on plants in tropical rain forests, typically on those plants in the understory. The drip tip is an adaptation which allows water on the leaf to collect, form a drop, and fall off. This reduces the amount of time a leaf's surface area is covered by water.
Early botanists surmised that the shedding of water prevented the growth of bryophytes and epiphyllous algae on the leaf's surface, but experimental evidence has found no such advantage, in fact, by clearing debris off of the leaf it makes it more likely that algae can colonize the leaf's apex. Modern research has found that the removal of water instead allows for better transpiration, prevents leaching of minerals such as potassium from the plant, and decreases the amount of sunlight being reflected. There is also evidence that the fast, frequent shedding of water plays a role in preventing parasitic fungi from establishing a hold on the leaf.
Drip tips can be found on ferns, herbaceous, and woody plants.
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