Our latest work
Computing methods for MPM and IPM construction and analysis
This introductory manual shows how to construct and analyze matrix projection models and discretized integral projection models using R, with the complete MPM projection environment offered by R package lefko3.
Urbanization drives the evolution of plants
We took part in a large study led by co-authors at the Unversity of Toronto that found that plants in urban environments evolve similarly in response to the common features of the urban landscape.
Individual history and population dynamics
Ecologists typically analyze population dynamics excluding individual history, but evidence suggests that this assumption is false. We have developed an R package, lefko3, that creates and analyzes matrix population models (MPMs) incorporating individual history.
Orchid life histories and demography
Orchids are prized for their unique and varied flowers. They have evolved special, long-lived life history strategies involving the production of dust seeds and dependence on fungal nutrition at least in the earliest stages of life. What other characteristics define their demography?
How do generalized interactions evolve?
Most of our understanding of coevolution comes from studies of specialist species. The complexity of generalist interactions has led too few studies of their coevolution. However, generalists must engage with partners that meet their ecological needs, and this must lead to an evolutionary pattern. How do these species coevolve?
What structures rangeland plant communities?
Rangeland plant communities are poorly understood, but the extreme nature of their environments drives much of their structure. Dispersal, evolution, and environmental filtering are all important, but in different ways. We investigated how.
What drives vegetative dormancy?
Vegetative dormancy has been found in over 100 species and 24 families of plants, but what causes it, how does it relate to life history and environment, and what are its evolutionary origins? We led an international team to answer these questions. Read news articles about this research on Nexus Media, Science Daily, or the Daily Mail.
The evolutionary origins of the lady's slippers
The lady's slipper orchids have some of the largest genomes in the orchid family. Why is this so? Our colleague Sarah Unruh led an international team to answer this question, using the transcriptomes of representative species from throughout the Orchidaceae.
Can we predict evolution?
Contemporary climate change may cause many extinctions in the near future, but it is also likely to lead to rapid evolution. Can we predict how this evolution will occur? We believe so, and show how using vegetative dormancy in 3 orchid species.
The ecology of ectomycorrhizal forest species
Dead matter affects not only ecosystems, but the populations that constitute them. The Shefferson lab contributed research on the impacts of deadwood on ectomycorrhizal diversity, to this study of the ecological effects of deadwood in a Pinus taeda plantation.
Why are some plants non-photosynthetic?
Some plant species shun the sunlight, instead relying on their soil-fungal symbionts as energy sources. In this study, we look into the evolutionary origins of this condition, linking microevolutionary demographic patterns to speciation.
Conserving European orchids
Orchid species are on the decline in Europe. In this study, we analyze environmental factors impacting the distributions of Red Listed species, and offer advice on management strategies to prevent extinction.
In the blogs
- Jun 2022: The Shefferson lab take on life as an ecologist in Japan.
- Dec 2020: Read our introduction to R package lefko3 on the Methods in Ecology and Evolution blog.
- Nov 2020: Read R. Shefferson's piece on the life histories and population dynamics of terrestrial orchids.
- Apr 2018: Read R. Shefferson's Ecological Inspirations piece in Journal of Ecology, about the paper that inspired him to become an evolutionary ecologist.
- June 2016: A commentary on a wonderful piece on latitudinal gradients in the Plant Kingdom by Zhang et al and in Journal of Ecology.
- July 2014: Read a commentary on a Journal of Ecology article dealing with why Rip van Winkle plants go dormant, particularly focused on life history costs.