The order Diptera (true flies) are named for their two wings because their hindwings have evolved into specialized mechanosensory organs called halteres. Flies use halteres to detect body rotations and maintain stability during flight and other behaviours. The most recently diverged dipteran monophyletic subsection, the Calyptratae, is highly successful, accounting for approximately 12% of dipteran diversity, and includes common families like house flies. These flies move their halteres independently from their wings and oscillate their halteres during walking. Here, we demonstrate that this subsection of flies uses their halteres to stabilize their bodies during takeoff, whereas non-Calyptratae flies do not. We find that flies of the Calyptratae are able to take off more rapidly than non-Calyptratae flies without sacrificing stability. Haltere removal decreased both velocity and stability in the takeoffs of Calyptratae, but not other flies. The loss of takeoff velocity following haltere removal in Calyptratae (but not other flies) is a direct result of a decrease in leg extension speed. A closely related non-Calyptratae species (D. melanogaster) also has a rapid takeoff, but takeoff duration and stability are unaffected by haltere removal. Haltere use thus allows for greater speed and stability during fast escapes, but only in the Calyptratae clade.

中文翻译：

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双翅目的起飞多样性

双翅目（真正的苍蝇）因其两个翅膀而得名，因为它们的后翅已进化成称为“halteres”的特殊机械感觉器官。苍蝇利用挂环来检测身体旋转并在飞行和其他行为过程中保持稳定性。最近分化的双翅目单系亚纲 Calyptraae 非常成功，约占双翅目多样性的 12%，其中包括家蝇等常见科。这些苍蝇独立于翅膀移动它们的缰绳，并在行走时摆动它们的缰绳。在这里，我们证明了这部分苍蝇在起飞过程中使用其缰绳来稳定身体，而非萼蝇科苍蝇则不然。我们发现，Calyptraae 蝇类能够比非 Calyptraae 蝇类飞得更快，而不会牺牲稳定性。去除Haltere会降低Calyptraae的起飞速度和稳定性，但不会降低其他果蝇的起飞速度和稳定性。萼蝇（但其他苍蝇）去除缰绳后起飞速度的损失是腿部伸展速度降低的直接结果。密切相关的非Calyptraae物种（D. melanogaster）也具有快速起飞，但起飞持续时间和稳定性不受haltere去除的影响。因此，使用 Haltere 可以在快速逃逸过程中提供更高的速度和稳定性，但仅限于 Calyptraae 分支。