Dr Philip Spradbery ‘To breed or not to breed? How the European wasp queen suppresses her daughters’ reproduction'

For the past 30 years Philip, a research entomologist, has been studying the European wasp to determine how the single queen, in a nest that can contain up to 5,000 adult worker wasps, prevents them from developing their ovaries and laying eggs. If the queen dies or is lost, within a week, many of the workers start laying eggs. Clearly, the queen has a potent method of keeping her workers sterile.

In this presentation Philip will take a pictorial look at the activities of a few of the solitary wasps he has come across over the years, and then will describe some of his work on the introduced European wasp in Canberra and the methods used to study how the queen controls social life in the wasp colony.

Of the 360 true wasp species (Vespoidae) in Australia, 90 per cent are solitary wasps which build their individual nests from mud and mass provision them with captured insect prey. There is no overlap of generations, no cooperation in rearing offspring and no division of labour. Social wasps in Australia are all either native Paper wasps (Polistes and Ropalidia species) or two introduced species, the European wasp (Vespula germanica) and the Common or English wasp (Vespula vulgaris).

Philip describes his career thus: "My scientific studies began with social wasps as a 16-year old schoolboy and will conclude with them as an octogenarian, it seems. Nearly 65 years of studying the social behaviour of wasps and hornets in Europe, Australia and Papua New Guinea has proved a very productive and exciting field of enquiry and with very little competition from other colleagues - an advantage of working with an animal that can cause pain or even death, and has modest commercial value! If I and my chemistry colleagues can define the identity of the sterilizing pheromone or ‘queen substance’ in the European wasp, that will be the culmination of a lifetime’s endeavour."