Pollination by birds
Hummingbirds have adaptations that allow them to reach the nectar of certain tubular flowers, thereby, aiding them in the process of pollination.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"OpenStax College, Pollination and Fertilization. October 23, 2013."
http://cnx.org/content/m44723/latest/Figure_32_02_03.jpg
OpenStax CNX
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