Our new PhD student Weizhao Sun starts in October 2019. A very warm welcome!
Our new technician Jana Salich starts in October 2019. A very warm welcome!
New paper by Princen et al.
Uli Ernst co-authored a manuscript titled “Honeybees possess a structurally diverse and functionally redundant set of queen pheromones”. Together with colleagues in Belgium and the USA, he identified new compounds in queen honeybees that suppress the ovary activation of worker honeybees.
“Queen pheromones, which signal the presence of a fertile queen and induce workers to remain sterile, play a key role in regulating reproductive division of labour in insect societies. In the honeybee, volatiles produced by the queen’s mandibular glands have been argued to act as the primary sterility-inducing pheromones. This contrasts with evidence from other groups of social insects, where specific queen-characteristic hydrocarbons present on the cuticle act as conserved queen signals. This led us to hypothesize that honeybee queens might also employ cuticular pheromones to stop workers from reproducing. Here, we support this hypothesis with the results of bioassays with synthetic blends of queen-characteristic alkenes, esters and carboxylic acids. We show that all these compound classes suppress worker ovary development, and that one of the blends of esters that we used was as effective as the queen mandibular pheromone (QMP) mix. Furthermore, we demonstrate that the two main QMP compounds 9-ODA and 9-HDA tested individually were as effective as the blend of all four major QMP compounds, suggesting considerable signal redundancy. Possible adaptive reasons for the observed complexity of the honeybee queen signal mix are discussed.”
For the full paper please click here, for supplementary material here, and for code and data here.
Princen, S. A., Caliari Oliveira, R., Ernst, U. R., Millar, J. G., van Zweden, J. S., Wenseleers, T. (2019) Honeybees possess a structurally diverse and functionally redundant set of queen pheromones. Proceedings of the Royal Society B - Biological Sciences 286: 20190517. https://doi.org/10.1098/rspb.2019.0517
New study by Eriksson and Gadau
Ti Eriksson and Jürgen Gadau co-authored a new study titled: "Intraspecifc variation in colony founding behavior and social organization in the honey ant Myrmecocystus mendax"
"Persistent cooperation between unrelated queens, a phenomenon termed primary polygyny, is rarely found in mature ant societies. In this article we present evidence that primary polygyny occurs in some populations of the desert honey ant Myrmecocystus mendax. Using genetic markers, we found that all mature colonies sampled in a population in the Sierra Ancha Mountains of central Arizona (USA) had multiple queens with a relatively high queen number, while the majority of mature colonies sampled in the Chiricahua Mountains of southeastern Arizona each had a single queen. Field and laboratory observations showed that Chiricahua queens found new colonies alone, whereas Sierra Ancha foundresses can also cooperate to initiate a new colony. Nestmate relatedness of mature Sierra Ancha field colonies was consistent with primary polygyny. In the laboratory, Sierra Ancha foundresses cooperatively established incipient colonies without conflict, and colonies with multiple queens produced more workers and repletes (honeypots) than single-queen colonies. This was in stark contrast to foundresses from the Chiricahua population, which showed strong aggression when artificially forced to found colonies together. When brood raiding was experimentally induced between laboratory Sierra Ancha colonies, queens from colonies with more workers had a higher survival probability, although in some cases the competing colonies fused and queens from both colonies continued to reproduce. Fusion between incipient ant colonies is a rare phenomenon, but could contribute to the high frequency of polygyny and high queen number in mature colonies in the Sierra Ancha population."