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James D. Lewis

Professor and Department Chair

Department of Biological Sciences
Fordham University
Larkin Hall - 160
441 East Fordham Road
Bronx, NY 10458

Louis Calder Center
53 Whippoorwill Rd., Box 887
Armonk, NY 10504

Phone: 718-817-3642 | 914-273-3078, ext. 24
Fax: 718-817-3645 | 914-273-6346


BS, The Pennsylvania State University, Biology, 1989
MS, The Pennsylvania State University, Ecology, 1989
PhD, Duke University, Botany, 1994
Postdoc, National Research Council Resident Research Associate (U.S. EPA, Western Ecology Division), Corvallis, Oregon, 1995–98

Research Interests

Invasive, non-native organisms, climate change, and habitat fragmentation have been identified as the three greatest threats to biodiversity globally. Research in my lab focuses on plant and community responses to these factors, and on the mechanisms that regulate responses to these factors. As an example, we are examining the broad impacts of urbanization on plants and communities. Research sites include the Calder Center, Central Park, Black Rock Forest, the New York Botanical Garden, and other preserves and parks in southern New York.

A related project is examining the mechanisms regulating plant responses to environmental factors such as climate change and urbanization. These projects include research on the relative contributions of developmental and physiological processes to plant responses to the environment. A key area of research is disentangling effects of plant age and plant developmental stage on responses to the environment. Much of this work has been funded by the NSF.

Other projects we are collaborating on include research on forest responses to loss of eastern hemlock (Tsuga canadensis) due to the hemlock woolly adelgid (HWA), an invasive non-native insect. The HWA generally causes extensive hemlock mortality at the stand level within five years of initial invasion. Decline of eastern hemlock may have far-reaching effects because of the unique suite of environmental characteristics associated with hemlock-dominated forests. Some objectives of our research are to examine how forest composition regulates the effects of the HWA on species diversity and productivity, and to examine the effects of changes in productivity on resource transfer between trophic levels. Much of this work has been funded by the USDA competitive grants program.

Research Opportunities

We have research opportunities for graduate, undergraduate, and high school students broadly interested in plant or forest ecology. While much of our research focuses on the impacts of invasive species, climate change, and urbanization on plants, and on the interactive effects of physiology and development in regulating plant responses to the environment, student projects also addresses a variety of other topics, reflecting the various interests of the students in my lab.

If you are interested in pursuing a graduate degree in our program, please feel free to contact me directly ( to find out more about our program.

I am also the assistant director of the Calder Summer Undergraduate Research (CSUR) program, an NSF-funded REU Site program. If you are interested in participating in this program, please feel free to contact me directly (, or check out our webpage for more information.

Selected Publications

* indicates undergraduate student

Ganzhorn, S., B. Perez-Sweeney, W.W. Thomas, F.A. Gaiotto and J.D. Lewis. 2015. Effects of fragmentation on density and population genetics of a threatened tree species in a biodiversity hotspot. Endangered Species Research 26:189-199.

Ganzhorn, S., W.W. Thomas, F.A. Gaiotto and J.D. Lewis. 2015. Spatial genetic structure of Manilkara maxima (Sapotaceae), a threatened tree species from the Brazilian Atlantic forest. Journal of Tropical Ecology 31:437-447. doi: 10.1017/S0266467415000292

Lewis, J.D., N. Phillips, B. Logan, R. Smith, I. Aranjuelo, S. Clark, C.A. Offord, A. Frith, M. Barbour, T. Huxman and D.T. Tissue. 2015. Rising temperature negates the stimulatory effect of elevated CO2 on growth and physiology of Wollemi pine (Wollemia nobilis). Functional Plant Biology doi: 10.1071/FP14256

Rubino, L.*, S. Charles*, A. Sirulnik, A.R. Tuininga and J.D. Lewis. 2015. Invasive insect effects on nitrogen cycling and host physiology are not tightly linked. Tree Physiology doi: 10.1093/treephys/tpv004

Cao, H., K. Butler*, M. Hussain* and J.D. Lewis. 2014. Variation in the fitness effects of mutations with population density and size in Escherichia coli. PLoS ONE 9:e105369

Zeppel, M.J.B., J.D. Lewis, N.G. Phillips and D.T. Tissue. 2014. Consequences of nocturnal water loss: a synthesis of regulating factors and implications for capacitance, embolism and use in models. Tree Physiology 34:1047-1055

Zeppel, M.J.B., J. Wilks and J.D. Lewis. 2014. Impacts of extreme precipitation and seasonal changes in precipitation on plants. Biogeosciences 11:3083-3093

Lewis, J.D., R.A. Smith*, O. Ghannoum, B.A. Logan, N.G. Phillips, and D.T. Tissue. 2013. Industrial-age changes in atmospheric [CO2] and temperature differentially alter responses of faster- and slower-growing Eucalyptus seedlings to short-term drought. Tree Physiology 33:475-488

Logan, B.A., J.S. Reblin, D.M. Zonana*, R.F. Dunlavey*, C.R. Hricko*, A.W. Hall*, S.C. Schmiege*, R.A. Butschek*, K.L. Duran*, R.J.N. Emery*, L.V. Kurepin*, J.D. Lewis, R.P. Pharis, N.G. Phillips and D.T. Tissue. 2013. Impact of eastern dwarf mistletoe (Arceuthobium pusillum) on host white spruce (Picea glauca) development, growth and performance across multiple scales. Physiologia Plantarum 147:502-513. doi: 10.111/j.1399-3054.2012.01681.x

Zeppel, M., B. Logan, J.D. Lewis, N. Phillips and D.T. Tissue. 2013. Why lose water at night? Disentangling the mystery of nocturnal sap flow, transpiration and stomatal conductance - when, where, who? Acta Horticulturae 991:307-312.

Smith, R.A.*, J.D. Lewis, O. Ghannoum and D.T. Tissue. 2012. Leaf structural responses to pre-industrial, current and elevated atmospheric [CO2] and temperature affect leaf function in Eucalyptus sideroxylon. Functional Plant Biology 39:285-296. doi:10.1071/FP11238

Tissue, D.T. and J.D. Lewis. 2012. Learning from the past: how low [CO2] studies inform plant and ecosystem response to future climate change. New Phytologist 194:4-6

Xu, C.Y., M.H. Turnbull, D.T. Tissue, J.D. Lewis, R. Carson, W.S.F. Schuster, D. Whitehead, A.D. Walcroft, J. Li and K.L Griffin. 2012. Age-related decline in stand growth is primarily due to mortality and not to changes in individual tree physiology, tree growth or stand structure in a Quercus-dominated forest. Journal of Ecology 100:428-440. DOI: 10.1111/j.1365-2745.2011.01933.x

Zeppel, M.J.B., J.D. Lewis, B. Chaszar, R.A. Smith, B.E. Medlyn, T.E. Huxman and D.T. Tissue. 2012. Nocturnal stomatal conductance responses to rising [CO2], temperature and drought. New Phytologist 193:929-938. doi: 10.1111/j.1469-8137.2011.03993.x

Lewis, J.D., N.G. Phillips, B.A. Logan, C. Hricko and D.T. Tissue. 2011. The relationship between leaf photosynthesis and dark respiration in six Eucalyptus species is regulated by daytime and nighttime stomatal conductance. Tree Physiology 31:997-1006. doi:10.1093/treephys/tpr087

Phillips, N.G., R. Attard*, O. Ghannoum, J.D. Lewis, B.A. Logan and D.T. Tissue. 2011. Impact of variable [CO2] and temperature on water transport structure-function relationships in Eucalyptus. Tree Physiology 31:945-952. doi: 10.1093/treephys/tpr047

Zeppel, M.J.B., J.D. Lewis, B. Medlyn, R. Duursma, M. Adams, D. Ellsworth, C. Barton, M. Forster, D. Eamus and D. Tissue. 2011. Interactive effects of elevated CO2 and drought on nocturnal water fluxes in Eucalyptus saligna. Tree Physiology 31:932-944. doi: 10.1093/treephys/tpr024

Lewis, J.D., J.K. Ward and D.T. Tissue. 2010. Phosphorus supply drives nonlinear responses of cottonwood (Populus deltoides) to glacial through future [CO2]. New Phytologist 187:438-448. doi: 10.1111/j.1469-8137.2010.03307.x

Logan, B.A., C.R. Hricko*, J.D. Lewis, O. Ghannoum, N.G. Phillips, R. Smith*, J.P. Conroy and D.T. Tissue. 2010. Examination of pre-industrial and elevated [CO2] reveals the temperature-dependent CO2 sensitivity of light energy partitioning at photosystem II in Eucalyptus. Functional Plant Biology 37:1041-1049. doi: 10.1071/FP10113

Ghannoum, O., N.G. Phillips, M.A. Sears*, B.A. Logan, J.D. Lewis, J.P. Conroy and D.T. Tissue. 2010. Photosynthetic responses of two eucalypts to industrial-age changes in atmospheric [CO2] and temperature. Plant, Cell and Environment 33:1671-1681. doi: 10.1111/j.1365-3040.2010.02172.x

Lewis, J.D., J.K. Ward and D.T. Tissue. 2010. Phosphorus supply drives nonlinear responses of cottonwood (Populus deltoides) to glacial through future [CO2]. New Phytologist 187:438-448.  doi: 10.1111/j.1469-8137.2010.03307.x 

Ghannoum, O., N.G. Phillips, J.P. Conroy, R.A. Smith*, R. Attard*, R. Woodfield, B.A. Logan, J.D. Lewis, and D.T. Tissue. 2010. Exposure to pre-industrial, current and future atmospheric [CO2] and temperature differentially affects growth and photosynthesis in Eucalyptus.  Global Change Biology 16:303-319.  doi:10.1111/j.1365-2486.2009.02003.x

Tissue, D.T. and J.D. Lewis. 2010. Photosynthetic responses of cottonwood seedlings grown in glacial through future atmospheric [CO2] vary with phosphorus supply. Tree Physiology 30:1361-1372. doi:10.1093/treephys/tpq077

Phillips, N.G., J.D. Lewis, B.A. Logan and D.T. Tissue. 2010. Inter- and intra-specific variation in nocturnal water transport in Eucalyptus. Tree Physiology 30:586-596. doi:10.1093/treephys/tpq009

Avolio, M.L., A.R. Tuininga, J.D. Lewis and M. Marchese*. 2009. Ectomycorrhizal responses to organic and inorganic nitrogen sources are context dependent. Mycological Research 113:897-907. doi:10.1016/j.mycres.2009.05.001 

Turner, G.D., J.D. Lewis, J.T. Mates-Muchin, W.F. Schuster and L. Watt*. 2009. Light availability differentially influences ectomycorrhizal fungal communities on oak seedlings grown in oak- and hemlock-associated soils. Canadian Journal of Forest Research 39:1247-1258. doi:10.1139/X09-051