Termites are just like the other eusocial insects: their societies are complex and varied: their colonies have a single queen-king pair, who monopolise reproduction; winged reproductives are produced and they disperse to form new colonies. However, it’s the helper castes that really make a colony tick: Most species have a soldier caste, whose just defend the colony; all colonies have individuals which specialise as foragers, nurses, and builders. Uniquely to termite societies, however, in some species the caste of an individual changes during their lifetime: they start life as a ‘worker nymphs’ (pseudergates) but can ‘grow up’ to become reproductives. Other termite species have true workers: adults that form a sterile, irreversible caste.
Remarkably, we understand little about the developmental and behavioural plasticity exhibited by termites. This range of caste plasticity provides excellent models for understanding phenotypic plasticity, the evolution of multiple phenotypes from a single genotype, and the regulatory role of the environment.
This studentship project will examine the regulation and molecular basis of castes in the simplest of termite societies which exhibit plastic pseudergates (e.g. Zootermopsis), and compare them with societies exhibiting more complex, ‘true workers’ (e.g. Macrotermes). Colonies from both types of societies can be easily kept in the lab, permitting experimental manipulation of phenotypes under controlled conditions. The student will design and implement experiments to test the phenotypic limits of these species, examine the resulting differences in gene expression that are associated with the different phenotypes, and potentially undertake functional knockdown of key genes involved in plasticity.