“I have been stung a dozen times but never complained. I guess that’s what love does to you.” Raghavendra Gadagkar’s love for Ropalidia marginata has lasted some 35 years and, as he wrote in a textbook on social behavior, it is unlikely he will ever abandon this love. The sociobiologist, who on Friday was awarded Germany’s highest civilian honour – The Cross of Order of Merit – has spent his scientific career studying the behavior patterns of this wasp found in South India. He finds that wasp interactions hold up a mirror to human societies.Gadagkar is a research professor at the Centre for Ecological Sciences at the Indian Institute of Science in Bengaluru and the president of the Indian National Science Academy. His love, R marginata, is a primitively social species of wasp. They were introduced to each other in Bangalore’s Central College in the early 1970s when Gadagkar was an undergraduate student. In a 2010 interview, Gadagkar said that during the classes that he found dull, he would watch honeycomb-like wasp nests wedged in window corners and the 20 or 30 wasps working, fighting and feeding their larvae. Gadagkar also met his wife Geetha while at Central College.A few years later, while at the IISc, Gadagkar was faced with one of the biggest decisions of his career – to move to the US or UK where he could work with advanced techniques of molecular biology or to stay in India to work with R marginata. He chose the wasp.



Photo credit: Wikimedia Commons

R marginata is a unique red-orange paper wasp whose social behaviour has plateaued at an intermediate stage of development. This gave Gadagkar an opportunity to explore how complex social behaviour emerges. Like many other wasps and bees and ants, R marginata colonies have a queen that rules the roost while others work towards building, maintaining and defending the colony. R marginata societies are made up of sitters, fighters and foragers.Gadagkar studied the wasps by marking each individual in the colony, developed a system to name them so that computer files could be created for each, and then computed time-activity budgets for every wasp. This had never been done before.Gadagkar’s research helped show how genetic relatedness of the individuals did not explain their social evolution. His biochemical analysis showed that queens mate, multiply and mix sperm from different males. Further, his pedigree analysis of the wasps showed that workers reared distantly related offspring. His experiments were also the first to show that wasp workers are unlikely to discriminate between different classes of relatives within their colony and that all individuals are not equally fit for social or solitary life.An adult female wasp, Gadagkar found, can stay an altruistic worker and work for the queen her remaining life. She can also selfishly leave, build her own nest, lay her own eggs, guard them, and bring her offspring to adulthood. Gadagkar's studies allowed him to make predictions about what percentage of the population of wasps would opt for the altruistic role and what percent would opt for the selfish role.Gadagkar and this team also demonstrated how a queen emerges from the undistinguished multitude in the colony. On removing the reigning queen, he saw that one of the workers in the colony became extremely aggressive – an aggression that accelerated the development of her ovaries. The new queen, however, quickly becomes a mild-mannered sitter. The secret to keeping the workers under her thumb, Gadagkar found, was a pheromone the queen slathers about her nest to prevent other wasps from reproducing.Gadagkar's work makes him the foremost expert on R marginata and one of the leading behavioural ecologists in the world. When not obsessing over his beloved wasp, Gadagkar champions the cause of more synergy between the sciences and humanities. He has served as chairman of the IISc’s Centre for Contemporary Studies since it was established 11 years ago. The centre endeavours to invites the best practitioners in philosophy, sociology, economics, law, literature, poetry, art, music, and cinema to create interactions between the world of the arts and the world of science.Gadagkar’s association with academia in Germany goes back 25 years to when he completed the final drafts of his monograph on R marginata at the Berlin Institute for Advanced Study. The German award recognises his substantial contribution to the fields of behavioural ecology and sociobiology and his work in strengthening the Indo-German research cooperation.