Trajectory of the tip of the paratuposa placentis wing (red is up, green is down) and elytra (blue). Springer Nature Courtesy photo
Beijing, January 20 (China News Network) -- A zoological paper published by the internationally renowned academic journal Nature said that the smallest insect on earth, a miniature beetle tassel, has a unique flight pattern and light, hairy wings that can explain its excellent flight ability. This research is important to improve people's understanding of the evolution of flight on a microscopic scale.
According to the paper, the speed at which insects fly generally depends on their size: the larger the insect, the faster it flies. This difference is usually due to the limitation of air friction, and on very small scales, this effect often exceeds the ability to fly. However, some miniature beetles seem to have overturned this rule, one example being paratuposa placentis, which is smaller than half a millimeter (395 microns) but can fly at a speed three times the size of a beetle.
Homoscale comparison of Paratasus placentis (left) with the single-celled organism Amoebic protozoa (right). Springer Nature Courtesy photo
Corresponding author Alexey Polilov of Moscow State University in Russia and colleagues 3D reconstructed and combined the wing structure and movement of the tassels, and the study showed that not only did the beetle have tassel wings, which were lighter than the membrane wings of the same size, but also the way these wings moved was previously unknown.
According to the research team, the wing-flapping cycle of this beetle is generated by two dynamic half-range strokes to produce a large upward force, followed by two slower recovery strokes to produce a small downward force. This cycle increases the amplitude of the wing flapping. The elytra (hardened forewing) acts as a brake to stop excessive oscillations. They argue that tasseled wings may require less muscle strength than heavier membrane wings, offsetting any potential increase in demand brought about by this unique mode of movement.
Paratylasa placentis in flight (top), 3D reconstruction of wing movements (middle) and visualization of airflow (bottom). Springer Nature Courtesy photo
The authors conclude that these adaptations may explain why insects retain excellent flight capabilities during miniaturization and represent a possible important component of their evolutionary success. (End)