Dr. Andrew MacDougall
Office: SSC 2459
Lab: SSC 2405/2406
B.A. - Dalhousie University 1987
M.Sc. - York University, 1991
Ph.D. - UBC 2004
NSERC Postdoctoral Fellow.
Department of Biology, University of Regina 2004 - 2006
Trophic Island Biogeography:
MacArthur and Wilson's classic model synthesizes a range of biogeographical processes to describe the regulation of diversity, but does not account for trophic interactions. We are testing how regional and local factors affect food web assembly in fragmented landscapes, focusing on insect-plant interactions in tallgrass prairie. (Head PI: Eric Harvey)
The Evolution of Spatial Pattern in Assembling Communities:
Most populations are non-randomly distributed, reflecting interactions between stochastic and deterministic niche-based processes that operate at a range of spatial and temporal scales. Using multi-hectare assembly experiments, we are testing how trophic dynamics, stochastic priority effects, and species sorting drive the evolution of spatial pattern in plant communities.
Global Drivers of Species Invasions:
Evidence linking invasion to the suppression of native diversity is equivocal. Local studies often describe negative associations between native diversity and invasion via competition, while regional studies often report habitat-mediated positive associations (the 'invasion paradox'). Using standardized multi-scale data from grasslands across the planet, this research tests how regional and local processes including human disturbances can be reconciled to explain the likely origins of the invasion paradox (a Nutrient Network project http://www.nutnet.umn.edu/).
This long-term study has determined that fire is critical for ecosystem function, but is highly destabilizing for populations of fire-dependent ground flora at local scales. Empirical data are being used to model the non-equilibrium dynamics of this system at local and regional spatial resolutions, illustrating 'a tale of two stabilities' defined by whether fire is present or continually suppressed (with Dr. Kevin McCann).
Plant-Pollinator Dynamics in Agricultural Landscapes:
Global pollinator declines threaten crop production, but the magnitude of pollinator collapse remains unclear. In collaboration with ALUS (http://www.norfolkalus.com/), this project tests how regional and local factors relating to habitat quality and farming practices influence the composition, abundance, and diversity of native pollinators on farms, and how those influences can ultimately affect yields of pollinator-dependent crops (Head PI: Caitlin Paterson).
Rodent Plagues on Prairie Diversity:
Small mammals influence diversity in many of the world's grasslands by selecting against palatable plants - the community can become dominated by the plants they mostly avoid. We are exploring how global environmental changes relating to plant invasion, trophic collapse, eutrophication, and habitat fragmentation may be magnifying the intensity of these 'rodent plagues', and the implications for ecosystem function including primary production and soil carbon dynamics (Head PI: Stefan Schneider).
Rarity is associated with vulnerability to extinction, yet most of the world's biological diversity is relatively uncommon in the systems where they occur. Rarity can be stabilized by a range of demographic processes that function within and across trophic levels, but many of these processes are being transformed by anthropogenic disturbances. This research explores whether stabilizing mechanisms persist despite disturbance or whether the likelihood of 'extinction debts' are increasing (with Drs. Ben Gilbert and Cort Griswold).
Duwyn, A. & MacDougall, A.S. When anthropogenic-based disturbances overwhelm demographic persistence mechanisms. Journal of Ecology.
Harvey, E. & MacDougall,A.S. Spatially heterogeneous perturbations homogenize the regulation of insect herbivores. American Naturalist.
Harvey, E. & MacDougall,A.S. Isolation and insect attack in recruiting oaks. American Midland Naturalist.
Chiuffo, M., MacDougall, A.S., & Hierro, J. Density-dependent soil feedbacks contribute to species coexistence in invaded grassland. Oecologia.
Seabloom,E., et al. Plant species origin determines dominance and response to nutrient enrichment. Nature Communications.
Fay,P. et al. Grassland productivity limited by multiple nutrients. Nature Plants.
Orrock, J. et al. A continent-wide study reveals strong relationships between regional abiotic conditions and post-dispersal seed predation. Journal of Biogeography.
Prober, S., Leff, J.W., Bates, S.T...MacDougall, A.S., et al. Plant diversity predicts beta diversity but not alpha diversity of soil microbes in grasslands worldwide. Ecology Letters.
Stevens, C., Lind, E, et al. Anthropogenic nitrogen deposition predicts grassland primary productivity worldwide. Ecology.
Hautier, Y., Seabloom, E., Borer, E. Adler, P., Harpole,W.S., Hillebrand,H., Lind, E., MacDougall, A.S. et al. Eutrophication weakens the stabilizing effects of diversity in natural grasslands. Nature 508: 521-525.
Borer, E., Seabloom, E., Gruner, D., Harpole, W. S.....MacDougall,A.S. et al. Herbivores and nutrients control grassland plant diversity via light limitation. Nature 508: 517-520.
MacDougall, A.S., Bennett, J., Firn, J., Seabloom E., Borer E., Lind,E. et al. Anthropogenic-based regional-scale factors most consistently explain plot level exotic diversity in grasslands. Global Ecology and Biogeography.
Harvey, E. & MacDougall, A.S. Trophic biogeography drives spatial divergence of community establishment. Ecology.
Thebault, A, Mariotte, P., Lortie,C.J., & MacDougall, A.S. Local management practices trump the effects of climate change and elevated CO2 on grassland functioning. Journal of Ecology.
Drystek,E & MacDougall A.S. Granivory reduces biomass and lignin concentrations in plant tissue during grassland assembly. Basic and Applied Ecology.
Vanness,B, MacDougall, A.S., & Wilson, S. Long-term root dynamics in native and invaded prairie following resources and defoliation. Functional Ecology.
Balogiannia, V. Wilson, S. Vanness, B., MacDougall, A. & Pinno B.Different root and shoot responses to mowing and fertility in native and invaded grassland. Rangeland Ecology and Management 67: 39-45.
MacDougall, A.S., McCann, K., Geisner, G. and Turkington, R. Diversity loss with persistent human disturbance increases vulnerability to ecosystem collapse. Nature 494: 86-89 (Cover article: February 2013).
Jones,N.T., Husband,B. and MacDougall A.S. Reproductive system of a mixed-mating plant responds to climate perturbation by increased selfing. Proceedings of the Royal Society of London B 280: 20131336.
Germain, R., Johnson**, L., Schneider**, S., Cottenie, K., Gillis, L., and MacDougall, A.S. Spatial variability in plant predation determines the strength of stochastic community assembly. American Naturalist 182: 169-179.
Ziter, C. and MacDougall, A.S. Nutrients and defoliation increase soil carbon inputs in grassland. Ecology 94: 106-116.
Suding, K., Fukami, T., Harpole, S. Kulmatiski, A., MacDougall, A.S., Stein, C., and Van Der Putten, W. Consequences of plant soil feedbacks in invasion. Journal of Ecology 101: 298-308.
Seabloom, E.W., Borer, E.T., Buckley, Y., Cleland,E., Davies,K.,Firn,J., Harpole,W.S., Hautier,Y., Lind,E., MacDougall, A.S., et al. Predicting invasion in grassland ecosystems: is exotic dominance the real embarrassment of richness? Global Change Biology 19: 3677-3687.
O'Halloran, L, Borer, E., Seabloom, E., MacDougall, A.S., et al. Regional contingencies in the relationship between aboveground biomass and litter in the world's grasslands. PLOS One 8(2): e54988.
Caplat, P.,Cheptou, P. ,Diez,J., Guisan, A., Larson, B., MacDougall, A.S., et al. Species movements in response to climate change: insights from invasions. Oikos 122: 1265-1274.
Leifso, A., MacDougall, A.S., Husband, B., Hierr,o J., Kochy, M., Partel, M. and Peltzer, D. Expansion of a globally pervasive grass occurs without substantial trait differences between home and away populations. Oecologia
Richardson, P., MacDougall, A.S., Stanley A., Kaye, T. and Dunwiddie P. (2012) Inversion of dominance-diversity relationships along a latitudinal stress gradient. Ecology.
Richardson, P., MacDougall, A.S., and Larson, D. (2012). Fine-scale spatial heterogeneity and incoming seed diversity additively determine plant establishment. Journal of Ecology.
Adler, P.B., Seabloom, E.W., Borer, E.T., Hillebrand, H., Hautier, Y., and MacDougall, A.S. (2011). Productivity is a poor predictor of plant species richness. Science 333: 1750-1753.
MacDougall, A.S., Rillig, M. and Klironomos, J. (2011). Weak conspecific feedbacks and exotic dominance in a species-rich savanna. Proceedings of the Royal Society B 278: 2939-2945.
Harnden, J., MacDougall, A.S. and Sikes, B. (2011). Field-based effects of allelopathy in invaded tallgrass prairie. Botany 89: 227-234.
Firn, J., Moore, J., MacDougall, A.S., Borer, E., Seabloom, E., HilleRisLambers, J., Harpole, S., Cleland, E. et al. (2011). Species abundance at home predicts abundance away in grasslands. Ecology Letters 14: 274-281.
MacDougall, A.S. and Wilson, S.D. (2011). Biological invasion doubles belowground productivity but not soil carbon. Ecology 92: 657-664.
Pinto, S.M and MacDougall, A.S. (2010). Dispersal limitation and environmental structure interact to restrict the occupation of optimal habitat. American Naturalist 175: 675-686.
Firn, J., MacDougall, A.S., Schmidt, S. and Buckely, Y.M. (2010). Early emergence and resource availability can competitively favour natives over a functionally-similar invader. Oecologia 163: 775-784.
MacDougall, A.S., Duwyn, A. and Jones, N. (2010). Consumer-based limitations drive oak recruitment failure. Ecology 91: 2092-2099.
BIOL*3110 Population Ecology
BIOL*3130 Conservation Biology
Felicia Syer (MSc)
Drew Anthony (MSc)
Michael Rogers (MSc)
Jenny McCune (Post Doctoral Fellow)
Kathryn Tisshaw (BSc)
Alyson Van Natto (BSc candidate)
Sean Hudson (BSc candidate)
Erin McKlusky (BSc candidate)