この小さな裏庭の虫は地上最速のバク転をする(This Tiny Backyard Bug Does the Fastest Backflips on Earth)

2024-08-29 ノースカロライナ州立大学(NCState)

<関連情報>

• https://news.ncsu.edu/2024/08/this-tiny-backyard-bug-does-the-fastest-backflips-on-earth/
• https://academic.oup.com/iob/article/6/1/obae029/7742965

オオグロスプリングテールDicyrtomina minutaのジャンプ性能と行動 Jumping Performance and Behavior of the Globular Springtail Dicyrtomina minuta

A A Smith, J S Harrison
Integrative Organismal Biology  Published:29 August 2024
DOI:https://doi.org/10.1093/iob/obae029

Synopsis

Springtails are among the most abundant arthropods on earth and they exhibit unique latch-mediated spring-actuated jumping behaviors and anatomical systems. Despite this, springtail jumps have not been well described, especially for those with a globular body plan. Here, we provide a complete description and visualization of jumping in the globular springtail Dicyrtomina minuta. A furca-powered jump results in an average take-off velocity of 1 ms^-1 in 1.7 ms, with a fastest acceleration to liftoff of 1938 ms^-2. All jumps involve rapid backwards body rotation throughout, rotating on average at 282.2 Hz with a peak rate of 368.7 Hz. Despite body lengths of 1–2 mm, jumping resulted in a backwards trajectory traveling up to 102 mm in horizontal distance and 62 mm in vertical. Escape jumps in response to posterior stimulation did not elicit forward-facing jumps, suggesting that D. minuta is incapable of directing a jump off a flat surface within the 90° heading directly in front of them. Finally, two landing strategies were observed: collophore-anchoring, which allows for an immediate arrest and recovery, and uncontrolled landings where the springtail chaotically tumbles. In comparison to other fast jumping arthropods, linear performance measures globular springtail jumps place them between other systems like fleas and froghoppers. However, in angular body rotation, globular springtails like D. minuta surpass all other animal systems. Given the extraordinary performance measures, unique behavioral responses, and understudied nature of these species, globular springtails present promising opportunities for further description and comparison.