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A Flower That Fits the Bill


The bill of the buff-tailed sicklebill hummingbird is perfectly shaped to collect nectar from deep within the Centropogon flower.

Buff-tailed sicklebill hummingbirds (Eutoxeres condamini) and Centropogon flowers can be found throughout the Amazon rainforests, from the lowland rainforests of Peru to the cloud forests of the Andes mountains, at about 2,500 feet, which run through Colombia, Ecuador, Peru, and Bolivia. The hummingbird seeks out the Centropogon flower for its nectar. When the bird sticks its bill deep within the flower to collect the high-energy food, it inadvertently rubs against the brush-like anthers of the flower, collecting pollen on its head. As the bird continues to feed on other flowers, it pollinates as it goes, and the Centropogon anthers can eventually rub the feathers off the top of the bird’s head, leaving most sicklebills with a pronounced bald spot! The shape of this hummingbird’s bill has coevolved with the shape of the flower, as both species benefit from an exclusive plant-pollinator relationship.

Image courtesy of Christopher C. Witt, PhD, University of New Mexico


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