A life-long fascination with animals still leaves Ben in awe of the diversity and creativeness in nature. Whether they crawl, run, fly, swim
Do Beetles Fly?
Yes, the majority of beetles can fly. This attribute dramatically enhances their options in terms of habitat and food sources. Almost anywhere you can think of that has water, vegetative foliage, roots, or decaying plant matter is likely home to one type of beetle or another. Another advantage that flight enables is the ability to escape danger.
The minority that cannot fly is commonly known as ground beetles (Carabidae). They account for around 40,000 species, representing about 8% of the worldwide beetle species population.
Why Don't All Beetles Fly?
Beetles are very adaptive insects, and Ground Beetles have evolved to take advantage of their environment. Consequently, some beetles have lost their back wings, and others have increased their dependency on using their "shields" as protective armor and are now unable to lift these front wings out of the way. The loss of flight as an escape means that these beetles have a vested interest in developing a strong exoskeleton that protects them from predators. A few beetles have no wings at all.
These non-flying beetles predominately prey on other insects. Although observations of these insects climbing plants to feed on caterpillars and aphids exist, they tend to feed at ground level.
Beetles' Dependency on Shield Armor
Ironclad beetles (Zopherinae) are considered the most heavily armored of all beetles. At one time, they were able to fly but have evolved incredibly strengthened armor by increasing the protein levels within the elytra to such a degree that they now out-perform all other beetles when it comes to exoskeletal strength. The trade-off for this species is that they cannot fly; instead, they live under the bark on trees or under rocks.
Do Beetles Have Wings?
Most have two pairs of wings; the front pair (often called shields) are more robust than those at the back. These "shields" are constructed from a material called "chitin" which makes them sturdier and more rigid. Consequently, they are not that effective as wings but protect the "real" more delicate wings underneath them.
Beetle Flight Mechanisms
There are two forms of flight deployed by beetles. The primary factor determining which format a particular species of beetle uses being driven mainly by the beetle's size. The larger beetles tend to rely on direct flight, with smaller beetles depending on an indirect flight mechanism.
- Direct flight is the term that describes beetles where their muscles are attached to wings.
- Indirect flight describes beetles where their muscles make the thorax oscillate, moving the wings.
The Critical Aspects of Beetle Flight Mechanisms
- The wing muscles insert directly at wing bases.
- It gives a higher degree of flexibility in flight (making it easier to change direction).
- Size: large beetles favor this mechanism.
- Muscles attach to the thorax rather than to the wings.
- The thorax deforms in shape, moving the wings.
- Size: small beetles favor this mechanism.
Aerodynamic Models Associated With Beetle Flight
There are essentially two aerodynamic models associated with beetle flight.
Leading Edge Vortex
The majority of beetles use this method, creating a spiraling leading edge vortex. I visualize this by thinking of an airplane wing's leading edge.
Clap and Fling
It is often referred to as the Weis-Fog Mechanism, named after the professor who pioneered insect flight studies.
This clap and fling mechanism describes how the wings clap together as they meet above the beetle's body before flinging apart. Flinging the wings apart causes air to be drawn in, creating a vortex over each wing.
Why Do Some Beetles Look So Clumsy When Flying?
This apparent clumsiness is likely due to some larger beetles keeping their legs dangling during flight. It can appear a cumbersome form of flight, as we are more used to seeing insects attempting to streamline their bodies by tucking their legs up close to their bodies.
Research suggests that far from being a disadvantage in flight, beetles with their legs dangling may help them maneuver more easily.
Creativity in the Skies
Beetles first took to the air 350 million years ago. They have adopted two main mechanisms to assist them with flight, the choice of which is primarily driven by size. This ability has undoubtedly assisted them in their incredible variety and spread around the world.
These fascinating creatures now number more than 300,000 different species worldwide, no other insect group can boast more. Hardly surprising then that beetles account for 20% of all types of living organisms. Beetles are prime examples of nature's creativity in conquering the skies.
- Lund University, (2012, May 29). "Beetle Flight: Flapping protective wings increase lift."
- "Insect Flight." Wikipedia.
- Ed. D. Thomas, (2016, April 6). "A Beetle Flight Muscle Displays Leg Muscle Microstructure." Biophysical Society.
- "Torkel Weis-Fogh." Wikipedia.
- "Beetle Flight." (2009, July 29). Life in the Undergrowth. BBC Nature.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.