Raghavendra Gadagkar

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Name: Raghavendra Gadagkar
Affiliations (Departments/Programs): 
Centre for Ecological Sciences
Research Areas: 
Behavior, Ecology, Evolution
Evolution of Social Life in Insects, Insect Ecology, Biogeography and Biodiversity, Social Organisation and Division of Labour in Insect Societies

After obtaining a PhD in molecular biology, I made an unusual twist in my career and turned my attention to the study of social insects.I have chosen the locally available Indian species of primitively eusocial wasp Ropalidia marginata. I and my team of students have pursued empirical and theoretical, field and laboratory, work on this single species for over 30 years. We have used a variety of approaches in our research, including biochemical and molecular techniques to show that queens mate multiply and mix sperm from different males, construction of pedigrees to show that workers rear rather distantly related brood, experiments to demonstrate that workers are unlikely to discriminate between different classes of relatives and that all individuals are not equally fit for social or solitary life. I developed a new class of theories, the focus of which is demography, a factor previously unexplored in this context. My “Assured Fitness Returns” model is an example of how group living can confer advantages over solitary life that are independent of genetic relatedness.

We also pursue, in parallel, an equally rigorous programme of experimental and theoretical work focusing on proximate questions of social organization and queen-worker interaction. We have discovered behavioural caste differentiation, pre-imaginal caste bias and a honey bee like age polyethism, in this species that lacks morphological castes. We have demonstrated that queens of R.marginata are behaviourally docile, meek sitters. This raises questions regarding how such queens become queens in the first place, how they inhibit worker reproduction and how they regulate non-reproductive activities of their workers. Attempts to answer these questions have begun to suggest that R.marginata queens start their career as aggressive queens and probably switch to pheromonal control of worker reproduction, which is why they can afford to be behaviourally meek sitters. As a response to this behaviour on the part of their queens, the workers have responded by self-organizing their own non-reproductive activities and thereby gaining indirect fitness without much prodding by the queen. Another remarkable feature of Ropalidia marginata society is the smooth and conflict-free succession that happens from one queen to the next. Through a series of experiments, we have demonstrated that even though human observers cannot predict the identity of the successor, the wasps themselves appear to know who the successor would be in the event of the death or loss of the queen. Indeed we have demonstrated that there is a long reproductive queue of cryptic successors with designated positions in the queue and all this happens in the presence of the old queen.

As the founder chair of the Centre for Contemporary Studies at IISc, Bangalore, I have initiated a new experiment that endeavours to engage some of the best practitioners of different disciplines in the human sciences, such as philosophy, sociology, economics, law, literature, poetry, art, music, cinema etc. and aims to forge meaningful interaction between the natural and human sciences with special focus on exposing graduate students to the diverse research methodologies of different disciplines and thus creating opportunities for them to rethink the foundations of their own disciplines.

Selected Publications: 

Bang,A. and Gadagkar,R. (2012). Reproductive queue without conflict in the primitively eusocial wasp Ropalidia marginata. Proc. Natl. Acad. Sci. USA. 109, 14494-14499.

Mitra,A., Saha,P., Chaoulideer,M.E., Bhadra,A. and Gadagkar,R. (2011). Chemical communication in Ropalidia marginata: Dufour’s gland contains queen signal that is perceived across colonies and does not contain colony signal. Journal of Insect Physiology, 57, 280-284.

Gadagkar, R. (2009). Interrogating an Insect Society. Proceedings of the National Academy of Sciences, USA, 106, 10407-10414.

Bhadra,A. and Gadagkar,R. (2008). We know that the wasps ‘know’: cryptic successors to the queen in Ropalidia marginata. Biol. Lett., 4, 634-637.

Agrahari,M. and Gadagkar,R. (2003). Juvenile hormone accelerates ovarian development and does not affect age polyethism in the primitively eusocial wasp, Ropalidia marginata. Journal of Insect Physiology, 49, 217-222.

Gadagkar, R. (2001). The Social Biology of Ropalidia marginata: Toward Understanding the Evolution of Eusociality. Harvard University Press, Cambridge, Massachusetts, USA.

Gadagkar, R. (1997). Survival Strategies - Cooperation and Conflict in Animal Societies. Harvard University Press, Cambridge, Massachusetts, USA and Universities Press, Hyderabad, India. (Complex) Chinese language edition, International Publishing Company Ltd., Taiwan (1999).Korean language edition, Purun Media Publishing Company (2001).

Gadagkar, R. (1997) The evolution of caste polymorphism in social insects: genetic release followed by diversifying evolution. Journal of Genetics, 76, 167-179.

Gadagkar, R. (1991). Demographic predisposition to the evolution of eusociality: A hierarchy of models. Proceedings of the National Academy of Sciences, U.S.A., 88,

Gadagkar, R. (1990). Evolution of eusociality : the advantage of assured fitness returns. Philosophical Transactions of the Royal Society of London B, 329, 17-25.


Member, German National Academy of Sciences Leopoldina, 2012.

Millennium Plaques of Honour, 2010, Indian Science Congress Association, Kolkata.

INSA S.N. Bose Research Professorship, 2010 –2015.

H.K. Firodia Award 2008 for Excellence in Science & Technology, 2008.

Elected Foundation Fellow, Entomology Academy of India, Chennai, 2007.

Award of Jawaharlal Nehru Birth Centenary Visiting Fellowship – 2007 of the Indian National Science Academy, New Delhi.

JC Bose National Fellowship, Department of Science & Technology, Government of India, 2006-2011.

Elected Foreign Associate, National Academy of Sciences, USA, 2006.

Member, Indian Delegation to participate in the meetings of the Inter-academy Panel held in Shanghai and the International Council for Science held in Suzhou, China, October 2005.

Prof. U.S.Srivastava Memorial Lecture Award of the National Academy of Sciences, India, 2005.

Prof. Rustum Choksi Award for Excellence in Research for Science for the Year 2004.

2002 VASVIK Award - for contribution by way of research to Environmental Sciences & Technology.

Swami Pranavananda Saraswathi Award in Environmental Science and Ecology for the year 2002.

Distinguished Visiting Scholar, University of Pretoria, South Africa, July 2003.

Non-Resident Permanent Fellow, Wissenschaftskolleg (Institute for Advanced Study) zu Berlin, 2002-2012.

Guest of the Rektor, Wissenschaftskolleg (Institute for Advanced Study) zu Berlin, Germany, 2001-2002.

Elected Fellow, Third World Academy of Sciences, 2001.

Schering-Fellow, Wissenschaftskolleg (Institute for Advanced Study) zu Berlin, Germany, 2000-2001.

Third World Academy of Sciences Award in Biology, 1999.

Elected Fellow, Indian Academy of Entomology, 1998.

Elected Fellow, The National Academy of Sciences, India, 1995.

B.P.Pal National Environment Fellowship on Biodiversity, Ministry of Environment & Forests, Government of India, 1995-1997.

Shanti Swarup Bhatnagar Award in Biological Sciences, 1993.

Elected Fellow, Indian National Science Academy, 1993.

Homi Bhabha Fellowship, November 1992 - October 1994.

B.M.Birla Science Prize in Biology, 1991.

Professor T.N.Ananthakrishnan Award, 1990-1991.

Saraswathi Narayanan award for Biological Sciences, 1990-91.

Elected Fellow, Indian Academy of Sciences, 1990.

Certificate of appreciation as a young scientist, Lion's Club International at the Regional meet, Bangalore, India, December, 1987.

Young Scientist Medal, Indian National Science Academy in Animal Sciences, 1985.

Young Scientist Award in Biological Sciences, Karnataka Association for the Advancement of Science, 1984.

Young Associate, Indian Academy of Sciences, 1984.

Dr. A. Krishna Murthy Award for the best paper, Society of Biological Chemists, India, 1982.

National Science Talent Scholarship-1969.