Juvenile hormone interacts with multiple factors to modulate aggression and dominance in groups of orphan bumble bee (Bombus terrestris) workers

Atul Pandey, Uzi Motro, Guy Bloch

Research output: Contribution to journalArticlepeer-review

Abstract

Juvenile hormone (JH) is a key regulator of insect development and reproduction. Given that JH commonly affects adult insect fertility, it has been hypothesized to also regulate behaviors such as dominance and aggression that are associated with reproduction. We tested this hypothesis in the bumble bee Bombus terrestris for which JH has been shown to be the major gonadotropin. We used the allatoxin Precocene-I (P-I) to reduce hemolymph JH titers and replacement therapy with the natural JH to revert this effect. In small orphan groups of workers with similar body size but mixed treatment, P-I treated bees showed lower aggressiveness, oogenesis, and dominance rank compared with control and replacement therapy treated bees. In similar groups in which all bees were treated similarly, there was a clear dominance hierarchy, even in P-I and replacement therapy treatment groups in which the bees showed similar levels of ovarian activation. In a similar experiment in which bees differed in body size, larger bees were more likely to be dominant despite their similar JH treatment and ovarian state. In the last experiment, we show that JH manipulation does not affect dominance rank in groups that had already established a stable dominance hierarchy. These findings solve previous ambiguities concerning whether or not JH affects dominance in bumble bees. JH positively affects dominance, but bees with similar levels of JH can nevertheless establish dominance hierarchies. Thus, multiple factors including JH, body size, and previous experience affect dominance and aggression in social bumble bees.

Original languageEnglish
Article number104602
JournalHormones and Behavior
Volume117
DOIs
StatePublished - Jan 2020

Keywords

  • Aggression
  • Bombus terrestris
  • Bumble bee
  • Division of labor
  • Dominance
  • Eusociality
  • Juvenile hormone
  • Reproduction
  • Social behavior

All Science Journal Classification (ASJC) codes

  • Endocrinology
  • Endocrine and Autonomic Systems
  • Behavioral Neuroscience

Fingerprint

Dive into the research topics of 'Juvenile hormone interacts with multiple factors to modulate aggression and dominance in groups of orphan bumble bee (Bombus terrestris) workers'. Together they form a unique fingerprint.

Cite this