Why is hard to beat the flies?

During the past two decades, Michael Dickinson has been asked hundreds of times by reporters about his research on the biology of insect flights. A question from the press always made him suffer: why are we hard to beat flies?

Dickinson said: 'I finally got the answer' . He is currently a professor of biological engineering at the California Institute of Technology (Caltech).

Thanks to the high-speed digital imaging technology with high resolution capturing the image of the fruit fly (Drosophila melanogaster) while facing a fly swatter slowly descending, Dickinson and Gwyneth Card graduate recently discovered the secret of the fly's hiding tricks. Long before the fly flew away, its tiny brain calculated the location of the near danger, in which it set up a plan to escape and put its foot in a favorable position to jump in the opposite direction. again with danger. All of these actions happen within 100 milliseconds after the fly detects the swatter.

Dickinson said: 'This can illustrate how the brain of the fly can process sensory information to become a rapidly-fitting motor response'.

For example, video recording is shown if the swatter is descending - in fact a black disc with a diameter of 14 cm - descending at a 50-degree angle towards the bald standing in the middle of a small platform right away in front of the fly, it will step between the center forward and lean backwards, then it will stand upright and stretch its legs to push the whole body backwards . However, when the danger appeared from behind, it would step in the middle slightly afterwards. Because flies have a 360-degree market, it can look behind it. If the threat comes from the right or left, the fly keeps the middle leg in its position but tiltes the whole body in the opposite direction before it jumps.

Researchers eventually found the secret of the fly's hiding tricks to avoid being hit.(Photo: iStockphoto / Michael Gatewood)

Dickinson said: 'We also found that the fly planned movements before flying, it calculated the body position at the time it saw the danger. When it detects an oncoming danger for the first time, its body may be in a certain position depending on the action it is taking such as combing, eating, crawling, or flirting. Our experiment showed that the fly somehow knew when it was necessary to create large and small posture changes to obtain a self-sufficiency before flying properly. This means that the fly must combine visual information from its eye; that information tells him where the danger comes from; Feeling mechanical information from the legs and letting him know how to move to get a proper posture before flying. '

The results opened up interesting things about the nervous system of flies, and showed that in its brain there is a map where the position of the threat falling 'is transformed into a mode of movement. Suitable legs and body before flying '. 'This is a rather complex type of sensory-motor metabolism, the study continues to explore the region of the brain responsible for this function,' Dickinson said.

Dickinson's research also points to an optimal method of helping us to fly flies. 'At the very least, don't beat when the fly is in the starting position, but aim a little further, predict how far the fly will jump when it detects your fly swatter.' . The article on the study of the title "Visually Mediated Motor Planning in the Escape Response of Drosophila" is published in the August 28 issue of Current Biology, which is researched by the National Institutes of Health and the National Science Foundation. support