“Ecological communities are shaped by two fundamental axes: space and time.”
Rudolf, VHW (2019). Ecol. Lett. 22(8): 1324-1338.
“History is not the past. It is the present. We carry our history with us.”
James Baldwin, I Am Not Your Negro
“Turbulence was everywhere, within every blade of grass, every drop of dew on a leaf, every cloud in the sky, and every star beyond. The turbulence was purposeless, but in huge quantities of purposeless turbulence, purpose took shape.”
Cixin Liu, The Dark Forest
My research centers on in the role of history in shaping community structure and function, mostly in vascular plants. From centuries-past legacies to timing differences on a scale of weeks, ecologists appreciate the impacts of historical conditions on present-day species interactions. As global change shifts timing of life history events, such as germination and flowering in plants, understanding the role of timing becomes increasingly important for forecasting community change. Similarly, the timing, frequency, and severity of disturbances like fire are shifting under global change. I am particularly motivated to understand processes governing ecological communities in North Carolina, where I was born and have grown up. On a longer scale, I am interested in the impacts of land use history, particularly violent Southern plantation agriculture, on the plant communities around my home.
Disturbance history and community resilience
“We live on a flammable planet where most terrestrial plants can burn under the right climatic conditions and many regions burn recurrently.”
Pausas, Keeley, and Schwilk (2017). J. Ecol. 105(2): 289-297.
“Strong effects of legacies on ecosystem recovery mean that contingencies […] will interact to affect ecosystem resilience.”
Johnstone et al. (2016). Front. Ecol. Environ. 14(7): 369-378.
Longleaf pine-wiregrass savannas are a pyrogenic Southern coastal plain ecosystem that have reduced in range due to settler fire suppression and logging in the last three centuries. Using a decade of data collected by the Wright lab in longleaf pine understory communities, I am investigating the role of disturbance frequency on plant community structure and resilience. I am particularly interested in how and why species vary in their sensitivity to fire history and the implications this variation has for community structure under varying fire regimes.
Priority effects, phenology, and species interactions
“Priority effects can be thought of as what happens when an orderly set of deterministic rules about community structure meets a rowdy bunch of stochastic assembly sequences.”
Diane Srivastava, The Paper Trail 2018.
Priority effects, in which an early-arriving species to a community affects the performance of a later-arriving species through niche preemption or modification, are increasingly studied. Shifts in seasonal timing of events (phenology), particularly early shifts in germination induced by warming, have implications for community dynamics when priority effects are important. Through a combination of greenhouse and fieldwork, I am manipulating germination timing using a C3 (cool-season) and C4 (warm-season) grass in an old field to understand the joint impacts of absolute seasonal timing and relative timing on these species’ interactions.
Unearthing Duke Forest
“The loss of stories sharpens the hunger for them. So it is tempting to fill in the gaps and to provide closure where there is none. To create a space for mourning where it is prohibited. To fabricate a witness to a death not much noticed.”
Hartman (2008). Small Axe 26: 1-14.
“Following settlement, much of the forest land was cleared for agriculture. Subsequently, less favorable economic conditions and decreased soil fertility resulted in widespread abandonment of land and its reversion to forest.”
Peet and Christensen (1987). BioScience 37(8): 586-595.
Duke Forest, established in the 1930s, is a resource for scientific educators and researchers. Along with Renata Kamakura and Kathleen Burns, I launched a working group in 2020 to explore the interrelated human, ecological, and intellectual history tied to the land that now makes up Duke Forest. Last year, we secured a Duke Provost grant for Reckoning with Race, Racism, and the History of the American South for this project. In summer 2022, I advised three students – an undergraduate at Duke, an undergraduate at NC Central University, and a masters student at Duke – through Duke’s Story+ digital humanities program. Check out their video and ArcGIS StoryMap here.
Feminist Critique of Ecological Theory
“[Our problem] is how to have simultaneously an account of radical historical contingency for all knowledge claims and knowing subjects […] and a no-nonsense commitment to faithful accounts of a ‘real’ world.”
Haraway (1988). Feminist Studies 14(3): 575-599.
Doing science is a social activity, and academic research is often governed by norms and assumptions. Feminist critique of scientific knowledge production provides a rich set of questions and tools to interrogate those assumptions and, sensu Helen Longino, strengthen objectivity of scientific claims. I am interested in the social, political, and historical context in which ecological research has been produced. In particular, competition-based frameworks, laden with Malthusian assumptions, dominate community ecology. In a recent paper, my co-authors Carlos Pardo De La Hoz and Lauren Carley investigate the roots of the competitive exclusion principle. It is available to read at no charge here.
Anita Simha 