本次阅读的三篇文献都是蜂学方面的新进展。我主要关心的是两方面问题：昆虫生理和行为特征的指标及测量方式（研究方法），以及熊蜂在环境胁迫下的反应机制（研究结论）。

Glass, J. R., Burnett, N. P., Combes, S. A., Weisman, E., Helbling, A., & Harrison, J. F. (2024). Flying, nectar-loaded honey bees conserve water and improve heat tolerance by reducing wingbeat frequency and metabolic heat production. Proceedings of the National Academy of Sciences, 121(4), e2311025121. https://doi.org/10.1073/pnas.2311025121

  • Focus on heat wave effects on honeybees
  • Honeybees avoid overheating by lowering wingbeat frequency
    • Reducing metabolic heat production is the result of lowering wingbeat frequency. Should not be mentioned separately as two mechanisms here.

“Many flying insects generate aerodynamic force by using a combination of mechanisms, including the sweeping motion of the wing (i.e., wing translation) and by creation of rotational vortices when the wings rotate before reversing direction. Insects that fly with a large stroke amplitude generate the bulk of their force from the wing translation phase, while those that fly with a small stroke amplitude primarily generate significant forces during wing rotation.”

  • To measure metabolic rate, they put individual bees in a chamber and sent air flow through the chamber. Evaporation and metabolic levels were measured by comparing the amount of H~2~O and C~2~O at the entrance and the exit of the chamber.
  • Flight muscle temperature is detected by inserting a micropobe into the center of the throax ouch! and then recording temperature data.

Kazenel, M. R., Wright, K. W., Griswold, T., Whitney, K. D., & Rudgers, J. A. (2024). Heat and desiccation tolerances predict bee abundance under climate change. Nature. https://doi.org/10.1038/s41586-024-07241-2

  • 16 years of abundance patterns for a hyper-diverse bee assemblage in a warming and drying region

  • Link bee declines with experimentally determined heat and desiccation tolerances, and use climate sensitivity models to project bee communities into the future.

  • Model prediction results

    • More homogeneous communities dominated by drought-tolerant taxa
    • Larger-bodied bees also dominated under intermediate to high aridity

  • “Climate studies have largely focused on geographical or phenological shifts, particularly potential phenological mismatches between bees and plants, often finding that mismatches are unlikely”

  • A smart index: the standardized precipitation evapotranspiration index (SPEI), which integrates temperature and precipitation

  • What climate change scenarios? During 2020–2100 for three Intergovernmental Panel on Climate Change (IPCC) scenarios representing low, moderate and extreme climate change

  • Climate sensitivity functions (CSFs) describe how an organism’s abundance tracks the distribution of a climate variable (mean and variance).

TODO: Check dataset to see if applicable for bumblebee species

Vaudo, A. D., Dyer, L. A., & Leonard, A. S. (2024). Pollen nutrition structures bee and plant community interactions. Proceedings of the National Academy of Sciences, 121(3), e2317228120. https://doi.org/10.1073/pnas.2317228120

  • Asked how pollen nutrition (relative protein and lipid content) sampled from 109 co-flowering plant species structured visitation patterns observed among 75 subgenera of pollen-collecting bees in the Great Basin/Eastern Sierra region (USA).
  • Important concept: nutritional niches
  • Bee–flower visitation data across eight sites in the Great Basin/Eastern Sierra region; combined with flower collection, nutrition analysis etc.