Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Fruit flies – fermented-fruit connoisseurs – are relentless party crashers

That fruit fly joining you just moments after you poured that first glass of cabernet, has just used its poppy-seed-sized brain to conduct a finely-choreographed search, one that’s been described for the first time by researchers at the University of Washington.

The search mission is another example of fruit flies executing complex behaviors with very little “computational” power, their brains having 100,000 neurons compared to house flies with 300,000 neurons and humans with 100 billion.

Floris van Breugel

Fruit flies use their antennae, the two pill shaped bumps sticking out from the front of the head, to detect odors.

Such computational efficiency is the envy of robot makers everywhere and of interest to neuroscientists wanting to know more about the brains of insects, animals and humans, according to Floris van Breugel, a UW post-doctoral researcher and lead author of a paper in the Feb. 3 issue of Current Biology. Michael Dickinson, UW professor of biology, is the paper’s co-author.

It’s the smell of fermentation that draws fruit flies, genus Drosophila, to your wine or the fruit ripening on the kitchen counter, the same smell that leads them to food in orchards and compost heaps outdoors.

If not already in your house when you pour your wine, fruit flies come calling from outside, following attractive odors through open doors and windows, being small enough to slip around the edges of screens if not simply passing through the openings in the mesh.

Fruit flies use their antennae to detect odors and it’s long been known they have a keen sense of smell. But odors travel in whiffs of scent, not steady streams, particularly outdoors in the wind. Nothing this detailed has ever been published about how free-flying fruit flies conduct successful searches, van Breugel said.

Using wind tunnel results, van Breugel and Dickinson described the reflexive surging upwind when an odor is detected and then the casting about when the whiff of scent is lost.

One surprise – and another example of how efficiently fruit flies use their neurons – was that in the presence of attractive odors, flies began using their eyes to look for roundish objects that might be fruit, van Breugel said. Without an attractive odor, flies ignore such objects.

“Because an odor plume can be so chaotic, just tracking the plume may or may not get them to the source of the smell,” he said. “So that’s when visual exploration starts to take over. They start to explore objects with visual contrast that could be the source of the odor. They land and if it’s not something to eat, they continue the search.” A glass of wine would be a contrasting shape, like fruit, that would merit their attention.

Flies, a dozen at a time, were observed trying to locate an attractive odor at one end of a 3-foot-long wind tunnel specially designed by Dickinson and his lab group. The tunnel generates a steady flow of air about the velocity of a light wind. Ten cameras collected more than 70 hours of flight data including 50,000 individual trajectories.

During the work, van Breugel wasn’t expecting to find evidence that flies would search for food visually. Then he noticed them exploring the floor of the wind tunnel, which had a checkerboard pattern, when odors were present but not in their absence. He devised an experiment without the checkerboard, but with a round shape on the floor and each of two walls. When an attractive odor was present, fruit flies explored around and landed on those shapes.

“Their senses interact in very sophisticated ways so what they smell literally influences what they see,” Dickinson said. “These interactions between vision and olfaction is part of the secret of how flies do so much with such tiny brains, they have clever ways to combine information from different senses.”

Modeling how insect brains function could be useful in developing efficient robots, indeed one of the funders of the research is the U.S. Air Force Office of Scientific Research.

“The study of behavior has often been very subjective, but we’re at the point where we can collect data with enough richness and information that we can come up with quantitative interpretations of what’s happening,” van Breugel said. For example, van Breugel and Dickinson modeled the behavior of flies as a simple algorithm of three reflexes: surging, casting and attraction to small visual features. An algorithm is a set of rules that precisely defines a sequence of operations whether in a brain or in a computer.

Using a computer simulation, the authors showed that this simple three-step algorithm could reliably guide a fruit fly to food without the need for a long range plan or mental map.

“As we quantify more of their behaviors in such detail, we could discover more efficient and robust algorithms for controlling robotic systems of all kinds,” van Breugel said.

“Although finding fruit flies in your wine or beer can be a bit annoying, I hope people will pause to admire the tenacity of these clever little creatures,” Dickinson said. “They are really just hungry animals looking for something to eat, and have no intention of ruining your happy hour.”

While working on this project in the Dickinson lab, van Breugel earned his doctorate from California Institute of Technology.

Other funding for the work came from the National Science Foundation, the Paul G. Allen Family Foundation and the Hertz Foundation.

For more information:
Van Breugel:
Dickinson: 206-221-1928,

Sandra Hines | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes
07.10.2015 | Karl-Franzens-Universität Graz

nachricht Flipping molecular attachments amps up activity of CO2 catalyst
06.10.2015 | DOE/Brookhaven National Laboratory

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

Im Focus: Physicists shrink particle accelerator

Prototype demonstrates feasibility of building terahertz accelerators

An interdisciplinary team of researchers has built the first prototype of a miniature particle accelerator that uses terahertz radiation instead of radio...

Im Focus: Simple detection of magnetic skyrmions

New physical effect: researchers discover a change of electrical resistance in magnetic whirls

At present, tiny magnetic whirls – so called skyrmions – are discussed as promising candidates for bits in future robust and compact data storage devices. At...

Im Focus: High-speed march through a layer of graphene

In cooperation with the Center for Nano-Optics of Georgia State University in Atlanta (USA), scientists of the Laboratory for Attosecond Physics of the Max Planck Institute of Quantum Optics and the Ludwig-Maximilians-Universität have made simulations of the processes that happen when a layer of carbon atoms is irradiated with strong laser light.

Electrons hit by strong laser pulses change their location on ultrashort timescales, i.e. within a couple of attoseconds (1 as = 10 to the minus 18 sec). In...

Im Focus: Battery Production: Laser Light instead of Oven-Drying and Vacuum Technology

At the exhibition BATTERY + STORAGE as part of WORLD OF ENERGY SOLUTIONS 2015 in Stuttgart, the Fraunhofer Institutes for Laser Technology ILT and for Ceramic Technologies and Systems IKTS will be showing how laser technology can be used to manufacture batteries both cost- and energy-efficiently.

In the truest sense, it’s all about watts at the Dresden-based Fraunhofer Institute for Ceramic Technologies and Systems IKTS and the Aachen-based Fraunhofer...

All Focus news of the innovation-report >>>



Event News

EHFG 2015: Securing healthcare and sustainably strengthening healthcare systems

01.10.2015 | Event News

Conference in Brussels: Tracking and Tracing the Smallest Marine Life Forms

30.09.2015 | Event News

World Alzheimer`s Day – Professor Willnow: Clearer Insights into the Development of the Disease

17.09.2015 | Event News

Latest News

Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

07.10.2015 | Life Sciences

Research on clean diesel engine technology: Reduce nitrogen oxide emissions and consumption

07.10.2015 | Machine Engineering

Graphene teams up with two-dimensional crystals for faster data communications

06.10.2015 | Information Technology

More VideoLinks >>>