Borrowing ideas from nature to improve methods of flight
Flight has fascinated mankind from early attempts at flight and the Wright Flyer to today’s supersonic jets and the ever-increasing use of drones. Many universities as well as the government are working on flight methods that more closely resemble the flight of birds and insects. In order to mimic nature, researchers seek to better understand the mechanisms behind natural flight, such as what muscles are used and how they contribute to flight. Our micro-CT scan of a bumble bee shows the muscle structure, which is the key to making a bee, which looks as though it shouldn’t be able to fly, move through the air with ease.
The Flight Anatomy
Insect flight is separated into two distinct methods, synchronous and asynchronous flight. Synchronous flight involves muscles that are attached directly to the wings and run vertically. There is one set of muscles for pulling the wings up and another for pulling them down. This type of contraction is similar to skeletal muscles in vertebrates.
Alternatively, asynchronous flight is unique to insects (such as bees, flies, and beetles) and is made up of vertical and longitudinal muscles that are found inside the thorax. As these muscles contract, the walls of the thorax deform, causing the wings to deflect up or down accordingly. The wings are in the up position when the vertical muscles contract and down when the longitudinal muscles contract (see Figure 2)1.
Figure 1. How asynchronous flight works with images from a bumble bee.
The importance of asynchronous flight is that it allows the organism to beat its wings at a much higher frequency, which is critical in getting the relatively large bee off ground. This type of flight is possible by each of the vertical and longitudinal muscles acting against each other. As the vertical muscles contract, the longitudinal muscles end up getting stretched, and vice versa. These muscle pairs are considered out of phase and the stretching of the opposite pair of muscles assists in the relaxation of the other pair. This stretching is similar to a rubber band that is pulled; when let go, the rubber band rapidly wants to retract back to its original state. The alternating muscle stretching and contracting saves the amount of energy required to maintain a high wing frequency, keeping the bee flying for hours1.
We hope you are intrigued with what this micro-CT scan shows us about insect flight. If you have a unique sample that you would like us to scan for you, please let us know. We would be glad to highlight you in the image of the month. Feel free to e-mail: brandon@microphotonics.com or call 610-366-7103 if you would like to submit a sample or learn more about our laboratory testing.
SCAN SPECIFICATIONS
System
Voltage
40kV
Current
200µA
Pixel Size
10µm
Rotation Step:
0.2
Scan Time
02:09:41 (HH:MM:SS)
Software
NRecon, DataViewer, CTVox
Location
Micro Photonics Imaging Laboratory, Allentown, PA
Works Cited:
- Richard W. Hill, Gordon A. Wyse, Margaret Anderson. Animal Physiology, 3rd Edition, chap. 20. (Sinauer Associates, 2012), accessed July 25, 2016. http://sites.sinauer.com/animalphys3e/boxex20.02.html.