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 H2O and C2O 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.