Dr Owen Lewis

University Lecturer in Ecology & Tutorial Fellow in Biology, Brasenose College

Dr Owen T. Lewis

Department of Zoology

University of Oxford

South Parks Road

Oxford OX1 3PS




Tel:  +44 (0)1865 271162

Fax: + 44 (0)1865 310447

I am a community ecologist and conservation biologist with a particular interest in tropical forest ecosystems.

I have wide research interests in population and community ecology and conservation biology. I welcome enquiries from well-qualified prospective graduate students interested in working in these areas.

Publications (please email me for reprints)

You can also view my Google Scholar publication profile.


Bagchi, R., Gallery, R.E., Gripenberg, S., Gurr, S.J., Narayan, L., Addis, C.E., Freckleton, R.P. & Lewis, O.T. (2014) Pathogens and insect herbivores drive rainforest plant diversity and composition. Nature, doi:10.1038/nature12911.

Morris, R.J., Gripenberg, S., Lewis, O.T. & Roslin, T. (2014). Antagonistic interaction networks are structured independently of latitude and host guild. Ecology Letters 17, 340-349.


Gripenberg, S., Bagchi, R., Gallery, R. E., Freckleton, R. P., Narayan, L., & Lewis, O.T. (2013). Testing for enemy‐mediated density‐dependence in the mortality of seedlings: field experiments with five Neotropical tree species. Oikos 123, 185-193.

Jeffs, C.T., and Lewis, O.T. (2013). Effects of climate warming on host–parasitoid interactions. Ecological Entomology 38, 1772-1781.

Comont, Richard F.; Purse, Bethan V.; Phillips, William; Kunin, William E.; Hanson, Matthew; Lewis, Owen T.; Harrington, Richard; Shortall, Christopher R.; Rondoni, Gabriele; Roy, Helen E.. 2013 Escape from parasitism by the invasive alien ladybird, Harmonia axyridis. Insect Conservation and Diversity. 10.1111/icad.12060

Mulder, C., Ahrestani, F. S., Bahn, M., Bohan, D. A., Bonkowski, M., Griffith, B. S., Guicharnaud, R. A., Kattge, J., Krogh, P. H., Lavorel, S., Lewis, O. T., Mancinelli, G., Naeem, S., Peñuelas, J., Poorter, H., Reich, P. B., Rossi, L., Rusch, G. M., Sardans, J., Wright, I. J. (2013). Connecting the green and brown worlds: elemental factors and trait-driven predictability of ecological networks. Advances in Ecological Research 49, 69-175.

Lewis, O.T., Ewers, R.M., Lowman, M. & Malhi, Y. (2013). Conservation of tropical forests: maintaining ecological integrity and resilience. In: Key Topics in Conservation Biology, ed. D.W. MacDonald & K.J. Willis. In Press.

Sutherland, W. J., Freckleton, R.P., Godfray, H.C.J., Beissinger, S.R., Benton, T., Cameron, D.D., Carmel, Y., Coomes, D.A., Coulson, T., Emmerson, M.C., Hails, R.S., Hays, G.C., Hodgson, D. J., Hutchings, M. J., Johnson, D., Jones, J. P.G., Keeling, M.J., Kokko, H., Kunin, W.E., Lambin, X., Lewis, O.T., Malhi, Y., Mieszkowska, N., Milner-Gulland, E.J., Norris, K., Phillimore, A.B., Purves, D.W., Reid, J.M., Reuman, D.C., Thompson, K., Travis, J.M.J., Turnbull, L.A., Wardle, D.A. and Wiegand, T. (2013). Identification of 100 fundamental ecological questions. Journal of Ecology, DOI: 10.1111/1365-2745.12025


Beynon, S.A., Slade, E.M., Mann D.J. & Lewis, O.T. (2012). Species-rich dung beetle communities buffer ecosystem services in perturbed agro-ecosystems. Journal of Applied Ecology 49, 1365–1372.

Beynon, S.A., Peck, M., Mann D.J. & Lewis, O.T. (2012) Consequences of alternative and conventional endoparasite control in cattle for dung-associated invertebrates and ecosystem functioning. Agriculture, Ecosystems & Environment 162, 36–44.

Novotny, V., Miller, S.E., Hrcek, J., Baje, L., Basset, Y., Lewis, O.T., Stewart, A.J.A., & Weiblen, G.D. (2012). Insects on plants: Explaining the paradox of low diversity within specialist herbivore guilds. The American Naturalist 179, 351-62.

Swinfield, T., Lewis, O.T, Bagchi, R. & Freckleton. R.P. (2012). Consequences of changing rainfall for fungal pathogen-induced mortality in tropical tree seedlings. Ecology and Evolution 2, 1408–1413

Klapwijk, M.J. & Lewis, O.T. (2012). Host-parasitoid dynamics in a fragmented landscape: holly trees, holly leaf miners and their parasitoids. Basic and Applied Ecology 13, 94–105.

Lawson, C., Mann, D.J. & Lewis, O.T. (2012). Dung beetles reduce clustering of tropical tree seedlings. Biotropica 44, 271-275.

Comont, R.F, Roy, H.E., Lewis, O.T., Harrington, R., Shortall, C., & Purse, B.V. (2012). Using biological traits to explain ladybird distribution patterns. Journal of Biogeography j.1365-2699.2012.02734.x

De Sassi, C., Lewis, O.T., & Tylianakis, J.M. (2012). Plant-mediated and nonadditive effects of two global change drivers on an insect herbivore community. Ecology 93:1892–1901.


Slade, E.M., Mann, D.J., and Lewis, O.T. (2011). Biodiversity and ecosystem function of tropical forest dung beetles under contrasting logging regimes. Biological Conservation 144, 166-174.

Bagchi, R., Philipson, C.D., Slade, E.M., Hector, A., Phillips, S., Villanueva, J.F., Lewis, O.T., Lyal, C.H.C., Nilus, R., Madran, A., Scholes, J.D., & Press, M.C. (2011) Impacts of logging on density dependent predation of dipterocarp seeds in a Southeast Asian rainforest. Philosophical Transactions of the Royal Society, Series B. (in press).

Gripenberg, S., Hamer, N., Brereton, T., Roy, D.B. & Lewis, O.T. (2011). A novel parasitoid and a declining butterfly: cause or coincidence? Ecological Entomology 36, 271-281.

Klapwijk, M.J. & Lewis, O.T. (2011). Spatial ecology of multiple parasitoids of a patchily-distributed host: implications for species coexistence. Ecological Entomology 36: 212-220.

Lewis, O.T. & Senior, M.J.M. (2011). Assessing conservation status and trends for the world’s butterflies:  the Sampled Red List Index approach. Journal of Insect Conservation, 15, 121-128.


Novotny, V., Miller, S.E., Baje, L., Balagawi, S., Basset, Y., Cizek, L., Craft, K.J., Dem F., Drew, R.A.I., Hulcr, J., Leps, J., Lewis, O.T., Pokon, R., Stewart, A.J.A. & Weiblen, G.D. (2010). Guild-specific patterns of species richness and host specialization in plant herbivore food webs from a tropical forest. Journal of Animal Ecology 79, 1193–1203.

Bagchi R., Swinfield T., Gallery R.E., Lewis O.T., Gripenberg S., Narayan L., Freckleton R.P. (2010). Testing the Janzen-Connell mechanism: pathogens cause overcompensating density dependence in a tropical tree. Ecology Letters 13, 1262-1269.

Marsh, C.J., Lewis, O.T., Said, I. & Ewers, R.M. (2010). Community-level diversity modelling of birds and butterflies on Anjouan, Comoro Islands. Biological Conservation 143: 1364-1374.

Staniczenko, P.P., Lewis, O.T., Jones, N.S. & Reed-Tsochas, F. (2010). Structural dynamics and robustness of food webs. Ecology Letters 13: 891–899.


Hayes, L., Mann, D.J., Monastyrskii, A.L. & Lewis, O.T. (2009). Rapid assessments of tropical dung beetle and butterfly assemblages: contrasting trends along a forest disturbance gradient. Insect Conservation and Diversity, 2, 153 - 241.

Klapwijk, M.J., Gröbler, B.C., Ward, K., Wheeler, D. & Lewis, O.T. (2009). Influence of experimental warming and shading on host-parasitoid synchrony. Global Change Biology, 16:102-112.

 Paniagua, M.R., Medianero, E. & Lewis, O.T. (2009). Structure and vertical stratification of plant galler - parasitoid food webs in two tropical forests. Ecological Entomology, 34: 310-332.

Lewis, O.T. (2009). Biodiversity change and ecosystem function in tropical forests. Basic and Applied Ecology, 10, 97-102.


Lewis, O.T. & Gripenberg, S. (2008). Insect seed predators and environmental change. Journal of Applied Ecology, 45, 1593-159

Lewis, O.T., Martin, M & Czaczkes, T.J. (2008). Effects of trail gradient on leaf tissue transport and load size selection in leaf-cutter ants. Behavioral Ecology, 19, 805-809. 

Basset, Y., Missa, O., Alonso A., Miller, S.E., Curletti, G., De Meyer, M., Eardley, C., Lewis, O.T., Mansell, M.W., Novotny, V. & Wagner, T. (2008). Changes in arthropod assemblages along a wide gradient of disturbance in Gabon. Conservation Biology, 22, 1552-63. [on-line here]

Basset, Y. Missa, O., Alonso, A., Miller, S.E., Curletti, G., De Meyer, M., Eardley, C., Lewis, O.T., Mansell, M.W., Novotny, V., & Wagner, T. (2008). Choice of metrics for studying arthropod responses to habitat disturbance: one example form Gabon. Insect Conservation and Diversity 1, 55-66.

Gröbler, B.C. & Lewis, O.T. (2008). Response of native parasitoids to a range-expanding moth. Ecological Entomology, 33, 453-463.

Menéndez, R., González-Megías, A., Lewis, O.T., Shaw, M.R. &  Thomas, C.D. (2008). Escape from natural enemies during climate-driven range expansion: a case study. Ecological Entomology, 33: 413-421.

Klapwijk, M.J. and Lewis, O.T. (2008). Effects of climate change and habitat fragmentation on trophic interactions. In: Tropical Biology and Conservation, edited by Arturo Bonet and Glória Carrion Villarnovo. Encyclopedia of Life Support Systems (EOLSS), UNESCO, Eolss Publishers, Oxford, UK. http://www.eolss.net/

Merrill, R., Gutiérrez, D., Lewis, O.T., Gutiérrez, J., Diez, S.B. & Wilson, R.J. (2008). Combined effects of climate and biotic interactions on the elevational range of a phytophagous insect. Journal of Animal Ecology 77, 145-155. 


Slade, E.M., Villanueva, J., Mann, D.J., and Lewis, O.T. (2007). Experimental evidence for the effects of dung beetle functional group richness and composition on ecosystem function in a tropical forest. Journal of Animal Ecology 76,1094-1104. 

Basset, Y., Corbara, B., Barrios, H., Cuénoud, P., Leponce, M., Aberlenc, H.-P., Bail, J., Bito, D., Bridle, J.R., Castaño-Meneses, G., Cizek, L., Cornejo, A., Curletti, G., Delabie, J.H.C., Dejean, A., Didham, R.K., Dufrêne, M., Fagan, L.L., Floren, A., Frame, D.M., Hallé, F., Hardy, O.J., Hernandez, A., Kitching, R.L., Lewinsohn, T.M., Lewis, O.T., Manumbor, M., Medianero, E., Missa, O., Mitchell, A.W., Mogia, M., Novotny, V., Oliveira, E.G. de, Ødegaard, F., Orivel, J., Ozanne, C.M.P., Pascal, O., Pinzón, S., Rapp, M., Ribeiro, S.P., Roisin, Y., Roslin, T., Roubik, D.W., Samaniego, M., Schmidl, J., Sørensen, L.L., Tishechkin, A., Van Osselaer, C. & Winchester, N.N. (2007).  IBISCA-Panama, a large-scale study of arthropod beta-diversity and vertical stratification in a lowland rainforest: rationale, description of study sites and field methodology. Bulletin de l'Institut Royal des Sciences Naturelles de Belgique- Entomologie, 77, 39-69.

Yackulic, C. & Lewis, O.T. (2007). Temporal variation in foraging activity and efficiency, and the role of hitchhiking behaviour in the leaf-cutting ant, Atta cephalotes.  Entomologia Experimentalis et Applicata 125, 125-134.

Tylianakis, J.M., Tscharntke, T. & Lewis, O.T. (2007) Habitat modification alters the structure of tropical host-parasitoid food webs. Nature, 445, 202-205.

Stewart, A.J.A., New, T.R. & Lewis, O.T.,(eds.) (2007). Insect Conservation Biology. CABI Publishing, Wallingford.

Lewis, O.T. & Stewart, A.J.A. & New, T.R. (2007). Insect Conservation Biology: Progress and prospects In: Insect Conservation Biology (eds A.J.A. Stewart, T.R. New & O.T. Lewis). CABI Publishing, Wallingford.

Lewis, O.T. & Basset, Y. (2007). Insect Conservation in Tropical Forests. In: Insect Conservation Biology (eds A.J.A. Stewart, T.R. New & O.T. Lewis). CABI Publishing, Wallingford.


Freckleton, R.P. & Lewis, O.T. (2006). Pathogens, density-dependence and the coexistence of  tropical trees. Proceedings of the Royal Society, Series B, 273, 2909-2916

Bell, T., Freckleton, R.P. & Lewis, O.T. (2006). Plant pathogens drive density-dependent mortality in a tropical tree. Ecology Letters 9: 569-574 

Lewis, O.T. (2006). Climate change, species-area curves and the extinction crisis. Philosophical Transactions of the Royal Society, Series B. 361: 163-171

Morris, R. J., & Lewis, O.T. & Godfray, H. C. J. (2005). Apparent competition and insect community structure: towards a spatial perspective. Annales Zoologici Fennici 42, 449 - 462

Morris, R.J., Lewis, O.T. and Godfray, H.C.J. (2004). Experimental evidence for apparent competition in a tropical forest food web. Nature 428, 310-313

Lewis, O.T., Memmott, J., LaSalle, J., Lyal, C.H.C., Whitefoord, C. & Godfray, H.C.J. (2002). Structure of a diverse tropical forest insect-parasitoid community. Journal of Animal Ecology 71, 855-873.

Thomas, C.D., Wilson, R.J. and Lewis, O.T. (2002). Short-term studies underestimate 30-generation changes in a butterfly metapopulation. Proceedings of the Royal Society of London, Series B 269, 563-569.

Morris, R.J and Lewis, O.T. (2002). The role of indirect interactions in structuring tropical insect communities. Oikos 97, 308-311.

Lewis, O.T. and Thomas, C.D. (2001). Adaptation to captivity in the butterfly Pieris brassicae, and the implications for ex situ conservation. Journal of Insect Conservation 5, 55-63.

Lewis, O.T. (2001) Effect of experimental selective logging on tropical butterflies. Conservation Biology 15, 389-400.

Godfray, H.C.J., Lewis, O.T. and Memmott, J. (1999). Studying insect diversity in the tropics. Philosophical Transactions of the Royal Society, Series B 354, 1811-1824.

Thomas, C.D., Glen, S.W.T., Lewis, O.T., Hill, J.K., and Blakeley, D.S. (1999). Population differentiation and conservation of endemic races: the butterfly, Plebejus argus. Animal Conservation 2, 15-21.

Hill, J.K., Thomas, C.D., and Lewis, O.T. (1999). Flight morphology in fragmented populations of a rare British butterfly, Hesperia comma. Biological Conservation 87, 277-283.

Thomas, C.D., Hill, J.K., and Lewis, O.T. (1998). Evolutionary consequences of habitat fragmentation in a localized butterfly. Journal of Animal Ecology 67, 485-497.

Lewis, O.T., Wilson, R.J., and Harper, M.C. (1998). Endemic butterflies on Grande Comore: habitat preferences and conservation priorities. Biological Conservation 85, 113-121.

Lewis, O.T. and Hurford, C. (1997). Assessing the status of the marsh fritillary butterfly (Eurodryas aurinia Rott.) - an example from Glamorgan (UK). Journal of Insect Conservation 1: 159-166.

Lewis, O.T., Thomas, C.D., Hill, J.K., Brookes, M.I., Crane, T.P.R., Graneau, Y.A., Mallet, J.L.B. and Rose, O.C. (1997). Three ways of assessing metapopulation structure in the butterfly Plebejus argus. Ecological Entomology 22: 283-293.

Hill, J.K., Thomas, C.D. and Lewis, O.T., (1996). Effects of habitat patch size and isolation on dispersal by Hesperia comma butterflies: implications for metapopulation structure. Journal of Animal Ecology 65: 725-735.

Thomas, C.D., Baguette, M. and Lewis, O.T. (2000). Butterfly movement and conservation in patchy landscapes. In: Behaviour and Conservation (eds. L.M. Gosling and W.J. Sutherland), pp.85-104. Cambridge: Cambridge University Press.

Thomas, C.D., Jordano, D., Lewis, O.T., Hill, J.K., Sutcliffe, O.L., and Thomas, J.A. (1999). Butterfly distributional patterns, processes and conservation. In: Conservation in a Changing World: integrating progress into priorities for action (ed. by G.M. Mace, A. Balmford and J.R. Ginsberg, pp. 107-138. Cambridge: Cambridge University Press.

Research Funding

2013-2018: Natural Environment Research Council (NERC) Thematic Consortium Grant (consortium chief PI), £2.3M: 'Biodiversity, Ecosytem Functions and Policy across a tropical forest modification gradient

2012-2015: Natural Environment Research Council (NERC) Standard Grant (lead PI in collaboration with Prof. Robert Freckleton, Sheffield), £406,119: ‘Natural enemies, climate, and the maintenance of tropical tree diversity

2010-2011: John Fell Fund (sole PI in collaboration with Dr Joe Wright, Dr Sofia Gripenberg, Dr Yves Basset), £7441: ‘Constructing a Tropical Forest Plant-seed predator Food Web

2007-2010: Natural Environment Research Council (NERC) Standard Grant (lead PI in collaboration with Prof Robert Freckleton (Sheffield) and Prof Sarah Gurr (Plant Sciences, Oxford), £541,230: ‘Plant Pathogens and Tropical Tree Diversity

2005-2006: Natural Environment Research Council (NERC) Small Grant (lead PI with Prof Robert Freckleton), £30,250: ‘Density dependence and the dynamics of tropical tree seedlings

2005-2006: Countryside Council for Wales research contract, £1,000: ‘Effects of climate change on host-parasitoid interactions

2005-2008: Biotechnology and Biological Sciences Research Council (BBSRC) Standard Grant (co-PI with Prof. S. Simpson). £237,475: ‘Optimal foraging for multiple nutrients: a comparison within and between feeding guilds

2002-2004: Nuffield Awards to Newly Appointed Lecturers (sole PI), £5,000: ‘Host-parasitoid dynamics in a fragmented landscape

2002-2005: Leverhulme Project Grant (co-PI with Prof. C.D. Thomas), £100,792: ‘Climate change and host-parasitoid interactions

2002-2005: Natural Environment Research Council (NERC) New Investigators Award (sole PI), £51,056: ‘Effects of habitat fragmentation on insect food webs