Bees Can Detect If Flowers Have Been Recently Visited By Checking?
Answer: Electrostatic Charges
In the animal kingdom, above all else, efficiency is king. Energy is far too precious to waste chasing after prey that will get away, roaming hunting grounds that are empty, or visiting food sources that have run dry. To that end, bees have developed a sophisticated way of avoiding flowers that have been recently visited by other bees (and aren’t worth the effort to visit again because the flower is depleted).
As bees fly about, they generate a slight positive static charge on their bodies. When they land on a flower, the positive static charge is transferred to the flower and takes a period of time to slowly dissipate (by a grounding action through the stem of the flower down into the earth). This charge, like perfume lingering in the air, is detected by other bees using specialized receptors in their antennae. They can read the electrostatic signature left behind by another bee’s visit to the flower and will avoid that flower until it has dissipated.
If you ever watch bees working over a large flowering tree, for example, you’ll notice that despite all the furious activity, individual flowers are rarely, if ever, revisited. Energy is too precious to waste making false stops and not taking home the maximum amount of nectar to the hive.
Image by David Lienhard/Wikimedia.