Abstract The evolution of eusociality represents one of the major and most successful life history transitions in animal evolution. The defining feature of eusocial societies is the reproductive
The evolution of eusociality represents one of the major and most successful life history transitions in animal evolution. The defining feature of eusocial societies is the reproductive division of labour, where the majority of females give up their reproduction to support the reproduction of the dominant female. This remarkable life-history strategy ensures that social insect colonies are highly efficient and explains the ecological dominance of social insects.
Evolutionary theory predicts that all females should want to maximise their own reproduction – to pass on their own genes to the next generation. But most female eusocial insects (subordinates or workers) forgo their own reproduction to support the dominant or queen. We have a good understanding of the theoretical reasons why this occurs; females can gain fitness by helping related individuals to reproduce. But the next major challenge is to understand how this has occurred; what genes pathways and processes drive this remarkable reproductive division of labour and how has it evolved?. My lab uses a combination of molecular approaches in both solitary and social bees to begin to address these questions.
In the honeybee, larvae destined to become queens are fed a diet of royal jelly which leads to substantial changes in adult morphology and behaviour; queen bees are larger, live a long time and have fully active ovaries. Adult workers do retain some ability to reproduce and mechanisms have evolved to constrain reproduction in workers maintaining the strict reproductive division of labour. In worker honeybees, sterility or reproductive constraint is conditional; If the queen is lost from the hive and cannot be replaced, worker bees will sense this change in their environment and respond by rapidly activating their own ovaries and initiating oogenesis. This causes a major change in their physiology and behaviour and is a prime example of phenotypic plasticity. Using molecular approaches (including RNA-seq and ChIP-seq) we now have a good understanding of how the honeybee ovary responds to the presence of the queen (and her pheromone) and are beginning to address how these processes have been co-opted into controlling reproduction in the evolution of eusociality.
(Tuesday) 1:00 pm - 2:00 pm
Carolin Kosiol, Niki Khan, Miguel Barbosa, Nick Jones