Some Bees Shout 'That Nectar's Ours!'
Some bees use bold intimidation rather than secrecy to claim prime nectar spots. Continue reading →
Imagine you're a bee and you just located a prime nectar source. You want to alert your hivemates, but not attract competitors. What should you do?
Some bees devise a special "whisper" to discretely let bees in their colony know about a food source, but others, new research has shown, "shout" it out loud with a message along the lines of, "This is good nectar and it's all ours or -- watch out!"
In the case of bees, the insects aren't actually shouting, but signalling to each other and outside bees using information-rich pheromone trails.
"It tells nestmates where to find good food and hints at a larger occupying force," explained Elinor Lichtenberg in a press release. Lichtenberg, a postdoctoral researcher at Washington State University, focused on species of singless Brazilian bees for her paper in the journal Current Biology.
The finding, she says, demonstrates how eavesdropping competitors can alter the evolution of animal signals -- even in unexpected ways.
"Our study provides a new way of looking at how eavesdroppers affect the evolution of animal communication signals," she said. "Until now, it was thought that eavesdroppers select against conspicuous signals, for example by more easily finding and eating prey that sings loudly. But our results show that eavesdroppers can help select for the same conspicuous signals that are easiest for intended recipients to detect and understand."
The hunt for good nectar can become fiercely competitive between some bee colonies, requiring bee species to develop critical communication strategies.
Among the Brazilian bees analyzed for the research, the bee species Trigona hyalinata is known to spy on species of Trigona spinipes bees to detect good foraging spots. But invading the other bees' nectar source can come at a price.
If individuals can recruit enough of their colony mates, then honing in on Trigona spinipes' source can be a good bet. But if they only manage to rally a small group of their colony mates to a competitor's source, they're likely to lose out to the other bees, or, worse, die fighting for it.
By sending out bold signals claiming a nectar source, species of Trigona spinipes hope to deter their eavesdropping competitors from even trying to invade their source.
"In this stingless bee system, with aggressive colonies jockeying for limited resources, more conspicuous food-recruitment signals indicate a higher likelihood that a resource will be harder to wrest away," said James Nieh, a professor of biology at UC San Diego who oversaw the research.
Photo: A Trigona spinipes bee. Credit: Wikimedia Commons
The U.S. Geological Survey is posting photos of insects on its
, offering a macro look at this hidden world. First up, this Festive Tiger Beetle (
) was found on top of a butte in Badlands National Park that had ancient windblown sand at its crest. Here, this sand specialist can build its long burrows.
This Agapostemon bee species is one of the most common native bees in the eastern United States. In almost any field there can be hundreds, if not thousands, of these bees visiting a wide variety of blooming plants. One of the largest of the sweat bees, it still goes undetected if you don't get down on your knees, face close, among the flowers. This one was collected at Colorado National Monument, Mesa County, Colo.
This wild bee (
), a female from Grand Tetons National Park, was collected as part of a study of climate change. Most species in this genus are black , but a few, like this one, are as the Latin in name implies, glittering jewels.
This unknown wasp was collected in Cecil County, Md.
This is an unknown species of Robber Fly from Charles County, Md. Robber flies, a very large and widespread type of fly, feed on many different kinds of insects, making them a key player in maintaining the insect balance in different environments.
One species of the rarely seen leafcutting bee, this is
from the sandhills of North Carolina. Leafcutter bees are so called because they cut plant leaves to create the cells in their nests. The bees tend to build their homes in rotted wood or in the strong stems of plants.
is a type of jumping spider. This one was found in Beltsville, Md., but
lives in fields and prairies across North America. It feeds on seasonal plants.
Eggplant Tortoise Beetles like eggplants (go figure), eating holes in the plants' leaves. From the underside, the insects look quite queenly, with their ruffled collars. This one was gathered at the Patuxent Wildlife Research Center, in Anne Arundel County, Md.
The Karner blue butterfly,
Lycaeides melissa samuelis
, is endangered. Karner blue butterflies feed on nectar from many different types of flowers, but their larvae can survive on the leaves of only one specific plant, which has been decimated by habitat loss or change.
Deer flies like this one, despite their groovy eyes, deliver a ferocious bite. And no wonder: when the female bites (males don't bite), she lacerates the skin and when the blood flows, sponges it up with her mouth. There are over 110 species of deer fly.
Centris bees, like this one, make their homes in holes, either in trees or in the ground.
The biggest visual difference between damselflies and dragonflies are their wing positions when resting. Dragonflies hold their wings open, while damselflies close them above their backs. This Ebony Jewelwing Damselfly (
) was found on a Beltsville, Md. stream.