Bumblebees Coax Pollen From Flowers With a Secret 'Knock'

Flowers unlock their pollen when bees use a special type of vibration. KQED Science

When it comes to unlocking the pollen from certain types of flowers, only a secret buzz will work — a buzz that bumblebees know how to perform. Not even honeybees, the most famous of pollinators, know how to crack the code.

Called buzz pollination, the strategy is utilized by some 20,000 flowering plant species including many agricultural crops we know and love like tomatoes, blueberries, potatoes and cranberries to name just a few. The plants make the bees work extra hard for a payoff of pollen.

"The bee bites down at the base of the anther, leaving little marks called bee kisses," reports KQED Science. "She 'unhooks' her flying muscles from her wings so she can contract them without taking flight. Then she begins to vibrate violently, a behavior scientists call sonication. The vibrations travel through her soft body to the flower and shake up the pollen grains trapped inside anthers. When she buzzes hard enough, the pollen shoots out of the top and covers the bee."

The result is a meal that can only be accessed through buzz pollination and thus has fewer competitors for the bumblebees.

The great short video by KQED Science above explains the technique.

Another strategy for buzz pollination was discovered within Australia's blue-banded bee. Rather than using wing muscles, this species uses a head-banging movement to access pollen, moving their heads up to 350 times per second to free the food source.

The importance of bumblebees as pollinators is now even more clear, since they're the only ones who can pollinate so many species of specialist flowering plants.