ant queen egg-marking signals matching deceptive laboratory simplicity with natural complexity蚂蚁皇后egg-marking信号匹配欺骗性实验室简单与自然复杂.pdf

Ant Queen Egg-Marking Signals: Matching Deceptive Laboratory Simplicity with Natural Complexity 1,2 ¨ 2 1 1,2 Jelle S. van Zweden *, Jurgen Heinze , Jacobus J. Boomsma , Patrizia d’Ettorre 1 Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark, 2 Biology I, University of Regensburg, Regensburg, Germany Abstract Background: Experiments under controlled laboratory conditions can produce decisive evidence for testing biological hypotheses, provided they are representative of the more complex natural conditions. However, whether this requirement is fulfilled is seldom tested explicitly. Here we provide a lab/field comparison to investigate the identity of an egg-marking signal of ant queens. Our study was based on ant workers resolving conflict over male production by destroying each other’s eggs, but leaving queen eggs unharmed. For this, the workers need a proximate cue to discriminate between the two egg types. Earlier correlative evidence indicated that, in the ant Pachycondyla inversa, the hydrocarbon 3,11- dimethylheptacosane (3,11-diMeC27) is more abundant on the surface of queen-laid eggs. Methodology: We first tested the hypothesis that 3,11-diMeC27 functions as a queen egg-marking pheromone using laboratory-maintained colonies. We treated worker-laid eggs with synthetic 3,11-diMeC27 and found that they were significantly more accepted than sham-treated worker-laid eggs. However, we repeated the experiment with freshly collected field colonies and observed no effect of treating worker-laid eggs with 3,11-diMeC27, showing that this