INSECT Lab, Division of Functional Morphology, Department of Zoology, Stockholm University, Svante Arrhenius väg 18b, 11418 Stockholm, Sweden.
Sorbonne Université, Faculté des Sciences et Ingénierie, 5 place Jussieu, 75005 Paris, France.
J Exp Biol. 2023 Apr 15;226(8). doi: 10.1242/jeb.245728. Epub 2023 Apr 19.
The impact of global warming on wild bee decline threatens the pollination services they provide. Exposure to temperatures above optimal during development is known to reduce adult body size but how it affects the development and scaling of body parts remains unclear. In bees, a reduction in body size and/or a reduction in body parts, such as the antennae, tongue and wings, and how they scale with body size (i.e. their allometry) could severely affect their fitness. To date, it remains unclear how temperature affects body size and the scaling of morphological traits in bees. To address this knowledge gap, we exposed both males and workers of Bombus terrestris to elevated temperature during development and assessed the effects on (i) the size of morphological traits and (ii) the allometry between these traits. Colonies were exposed to optimal (25°C) or stressful (33°C) temperatures. We then measured the body size, wing size, antenna and tongue length, as well as the allometry between these traits. We found that workers were smaller and the antennae of both castes were reduced at the higher temperature. However, tongue length and wing size were not affected by developmental temperature. The allometric scaling of the tongue was also affected by developmental temperature. Smaller body size and antennae could impair both individual and colony fitness, by affecting foraging efficiency and, consequently, colony development. Our results encourage further exploration of how the temperature-induced changes in morphology affect functional traits and pollination efficiency.
全球变暖对野生蜜蜂减少的影响威胁到它们提供的传粉服务。已知在发育过程中暴露在高于最佳温度下会降低成虫的体型，但它如何影响身体部位的发育和比例仍不清楚。在蜜蜂中，体型的减小和/或身体部位的减小，如触角、舌头和翅膀，以及它们与体型的比例（即它们的比例）可能会严重影响它们的适应能力。迄今为止，温度如何影响蜜蜂体型和形态特征的比例仍不清楚。为了弥补这一知识空白，我们在发育过程中让熊蜂的雄性和工蜂暴露在高温下，并评估了（i）形态特征的大小和（ii）这些特征之间的比例关系的影响。殖民地暴露在最佳（25°C）或应激（33°C）温度下。然后，我们测量了体型、翅膀大小、触角和舌头长度，以及这些特征之间的比例关系。我们发现，在较高的温度下，工蜂体型较小，两性的触角都变短。然而，舌头长度和翅膀大小不受发育温度的影响。舌头的比例也受到发育温度的影响。较小的体型和触角可能会通过影响觅食效率，从而影响个体和群体的适应能力，进而影响群体的发展。我们的研究结果鼓励进一步探索形态变化如何影响功能特征和传粉效率。
