PaleoEcoGen seminar series
The PaleoEcoGen Working group invites anyone interested to attend a monthly Webinar Series.
Upcoming Seminars
The last seminar for the semester was hosted on 21 April 2022.
Information about upcoming seminars will be communicated asap.
Past Seminars
21 April 2022
"Tracking abrupt ecological change in the Quaternary fossil record"
Dr. Allison Stegner (Postdoctoral Scholar, Department of Biology & Jasper Ridge Biological Preserve, Stanford University, USA)
> Watch recoding
Short bio
M. Allison Stegner is a paleoecologist whose research synthesizes modern, historic, and paleoecologic records to study how species diversity and abundance have changed through time in response to past environmental changes. She has a B.S. in Biology (emphasis on Ecology and Evolution) from Stanford University, and Ph.D. in Integrative Biology from the University of California, Berkeley. From 2016-2019, she was a postdoctoral scholar at the University of Wisconsin, Madison where she was a member of the Abrupt Change in Ecological Systems Group, an interdisciplinary team studying the drivers and consequences of abrupt ecological changes using theoretical, modeling, and empirical approaches. Stegner is currently a postdoctoral scholar at Stanford University, where she is using lacustrine sediment cores to study the geologic basis for defining the Anthropocene.
24 March 2022
"Detecting change in palaeoecological time series, old and new"
Dr. Gavin Simpson (Department of Animal Science, Aarhus University, Denmark)
> Watch recording
Short bio
Gavin Simpson is a statistical ecologist with particular interests in spatiotemporal change in ecological communities and ecosystems and the methods used to detect them. Trained initially as a palaeoecologist, the statistical challenges posed by palaeoenvironmental data have shaped Gavin’s subsequent research interests, which include trend estimation using generalized additive models and methods for summarizing and analyzing multivariate palaeoecological data sets.
24 February 2022
"Detecting critical transitions and signals of changing resilience from paleo-ecological records: a multivariate approach"
Dr. Zofia Taranu (Aquatic Contaminants Research Division, Environment & Climate Change, Canada)
> Watch recording
Brief description
The objective of my research is to understand how human-mediated local stressors (e.g., land use, eutrophication) interact with regional drivers (e.g., climate) to alter freshwater communities and ecosystem stability. In particular my work has examined how biodiversity loss vs. gain may lead to changes in multi-trophic species interactions, which in turn may lead to the dominance of harmful species (e.g., cyanobacteria) and destabilization of aquatic ecosystems via regime shifts.
I am especially interested in whether these interactions have become more pronounced in recent times or in certain locations, and identifying the processes that cause discrepancies across studies. I use a combination of meta-analyses, landscape paleolimnology and numerical ecology to identify data gaps, generalities and long-term drivers of shifts in water quality, community composition and ecosystem functions.
During this talk, I will highlight some of my recent work on detecting regime shifts and critical transitions with paleolimnological records. In particular, I will build on an earlier study (Taranu, Carpenter, et al. 2018) by extending our univariate models to multivariate models. By examining changes in the functional composition of the community (multivariate models), we hope to provide a better diagnostic of an approaching critical transition than that of the univariate models. This would also allow to test whether regime shifts and critical transitions could be upscaled to the whole aquatic ecosystem. That is, whether resilience indicators at one trophic level are detectable in other components of a food web.
27 January 2022
"Spatial variability of Past Trajectories of alpine ecosystems"
Dr. Charline Giguet-Covex (EDYTEM, France)
> Watch recording
Short bio
Charline Giguet-Covex did a PhD thesis in sedimentology and geochemistry at the EDYTEM laboratory (France). Her research was focused on the reconstruction of past hydrological changes in the alpine area through the study of the erosion dynamic. She is also interested in the reconstruction of past soil evolution and lake ecological state changes, both in large and small lakes. Then during two Postdoc positions (at LECA, France and BioArch-University of York, UK), she acquired skills in sedaDNA to trace agropastoral activities and vegetation changes and assess the impact of these human activities on the landscape changes, including modifications of the erosion cycle.
Now, she is a CNRS researcher at EDYTEM with a main interest in reconstructing past trajectories of mountain agro-ecosystems.