Honey bees dilute propolis, forming drops on a wooden surface with a diameter from 35.7 microns to 1500.0 microns (N=450). The average diameter of the drop in the experiment was 562 μm (N=450), and the deviation of the contact line of the drop from roundness was 39.0 μm. (N=450), and the distance from the edge of the glass substrate to the center of the drop was 27944.0 μm on average. N = 450).For the first time, it has been established that during the manipulation of propolis, honey bees can lose parts of it due to its dilution by enzymes of the mandibular glands. Microscopic studies of the color and content of the drops confirm the hypothesis that it is vegetable resin. At the same time, the question of composition remains open for us.

Dvykaliuk, R., Adamchuk, L., & Pylypko, K. (2022). Propolis Drops as Evidence for Dilution of Propolis by Honey Bees? Bee World, 99(4), 110–116. https://doi.org/10.1080/0005772x.2022.2094139