Making a beeline for the nectar

June 20, 2013

Bumblebees searching for nectar go for signposts on flowers rather than the bull's eye. A new study, by Levente Orbán and Catherine Plowright from the University of Ottawa in Canada, shows that the markings at the center of a flower are not as important as the markings that will direct the bees to the center. The work is published online in Springer's journal, Naturwissenschaften - The Science of Nature.

The first time bees go out looking for nectar, which visual stimuli do they use to identify that first flower that will provide them with the reward they are looking for? Orbán and Plowright test the relative influence of the type of floral pattern versus pattern position in a group of bumblebees that have never searched for nectar before i.e. flower-naive bees.

In a series of two experiments using both radio-frequency identification technology and video recordings, the researchers exposed a total of over 500 flower-naive bees to two types of patterns on artificial clay flowers: concentric versus radial. Concentric patterns are comprised of circles or rings with the same center. Radial patterns are composed of distinctly colored lines extending from the outside of the flower, converging at the center where nectar and pollen are usually found. The patterns tested were in one of two positions on the artificial flowers: either central or peripheral, on the corolla (or petals) of the flower.

They found that both visual properties had significant effects on flower choice. However, when pitted against each other, pattern type trumped position. Bees preferred radial patterns over concentric patterns. When the influence of radial patterns in the center was compared with the influence of radial patterns on the periphery, there was little difference in the bees' response. It appears that the visual cues from the radial pattern guide the bees to the periphery of the flower. Once there, they will find the rewarding nectar in the center of the flower.

The researchers conclude: "Which came first: the chicken or the egg? The behavior of bees has been shaped over the course of evolution as adaptations to flower appearance. Equally, floral appearance has evolved in ways that cater towards bees' visual and olfactory abilities. Flowers may be taking advantage of a principle that will be familiar to students and teachers alike: the bees need not be shown the food itself, but rather, how to find it."
-end-
Reference

Orbàn, L.L. & Plowright, C.M.S. (2013). The effect of flower-like and flower-unlike visual properties on choice of unrewarding patterns by bumblebees. Naturwissenschaften - The Science of Nature; DOI 10.1007/s00114-013-1059-9

The full-text article, photos and a video clip are available to journalists on request.

Springer

Related Bees Articles from Brightsurf:

Two pesticides approved for use in US harmful to bees
A previously banned insecticide, which was approved for agricultural use last year in the United States, is harmful for bees and other beneficial insects that are crucial for agriculture, and a second pesticide in widespread use also harms these insects.

Native bees also facing novel pandemic
There is growing evidence that another ''pandemic'' has been infecting bees around the world for the past two decades, and is spreading: a fungal pathogen known as Nosema.

Bees grooming each other can boost colony immunity
Honeybees that specialise in grooming their nestmates (allogroomers) to ward off pests play a central role in the colony, finds a new UCL and University of Florence study published in Scientific Reports.

Microalgae food for honey bees
A microscopic algae ('microalgae') could provide a complete and sustainably sourced supplemental diet to boost the robustness of managed honey bees, according to research just published by Agricultural Research Service scientists in the journal Apidologie.

Bees point to new evolutionary answers
Evolutionary biology aims to explain how new species arise and evolve to occupy myriad niches -- but it is not a singular or simplistic story.

Quantifying objects: bees recognize that six is more than four
A new study at the University of Cologne proves that insects can perform basic numerical cognition tasks.

Prescribed burns benefit bees
Freshly burned longleaf pine forests have more than double the total number of bees and bee species than similar forests that have not burned in over 50 years, according to new research from North Carolina State University.

Insecticides are becoming more toxic to honey bees
Researchers discover that neonicotinoid seed treatments are driving a dramatic increase in insecticide toxicity in U.S. agricultural landscapes, despite evidence that these treatments have little to no benefit in many crops.

Neonicotinoids: Despite EU moratorium, bees still at risk
Since 2013, a European Union moratorium has restricted the application of three neonicotinoids to crops that attract bees because of the harmful effects they are deemed to have on these insects.

Bees 'surf' atop water
Ever see a bee stuck in a pool? He's surfing to escape.

Read More: Bees News and Bees Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.