Essner Richard L, Pereira Rudá E E, Blackburn David C, Singh Amber L, Stanley Edward L, Moura Mauricio O, Confetti André E, Pie Marcio R
Department of Biological Sciences, Southern Illinois University Edwardsville , Edwardsville, IL, USA.
Programa de Pós-Graduação em Zoologia, Universidade Federal do Paraná, Curitiba, Paraná, Brazil.
Sci Adv. 2022 Jun 17;8(24):eabn1104. doi: 10.1126/sciadv.abn1104. Epub 2022 Jun 15.
Miniaturization has evolved repeatedly in frogs in the moist leaf litter environments of rainforests worldwide. Miniaturized frogs are among the world's smallest vertebrates and exhibit an array of enigmatic features. One area where miniaturization has predictable consequences is the vestibular system, which acts as a gyroscope, providing sensory information about movement and orientation. We investigated the vestibular system of pumpkin toadlets, (Anura: Brachycephalidae), a clade of miniaturized frogs from Brazil. The semicircular canals of miniaturized frogs are the smallest recorded for adult vertebrates, resulting in low sensitivity to angular acceleration due to insufficient displacement of endolymph. This translates into a lack of postural control during jumping in and represents a physical constraint resulting from Poiseuille's law, which governs movement of fluids within tubes.
在全球热带雨林潮湿的落叶层环境中，蛙类反复进化出了小型化特征。小型蛙类是世界上最小的脊椎动物之一，并展现出一系列神秘的特征。小型化产生可预测后果的一个领域是前庭系统，它就像一个陀螺仪，提供有关运动和方向的感官信息。我们研究了南瓜蟾（无尾目：短头蟾科）的前庭系统，这是一类来自巴西的小型化蛙类。小型化蛙类的半规管是成年脊椎动物中记录到的最小的，由于内淋巴位移不足，导致对角加速度的敏感性较低。这导致它们在跳跃时缺乏姿势控制，这是由泊肃叶定律导致的一种物理限制，该定律支配着管内流体的运动。
