Monthly Archives: August 2021

NSF LTREB award, recruiting a new PhD student soon

Castle Peak site in the Sierra Nevada

I am excited to announce that my (collaborative) NSF LTREB project on predicting the success of montane (butterfly) species in an era of climatic upheaval has been funded. This project builds on a long-term data set generated by Art Shapiro at UC Davis and is a collaborative project with Matt Forister at the University of Nevada. I will be advertising soon for a PhD student to work on this project starting fall 2022. The award abstract follows:

The history of life on Earth has many periods of mass extinction, when many species cease to exist. These periods are usually studied through use of fossils. Although fossils have revealed a lot about extinction, they’ve been unable to solve the basic riddle of why some species go extinct and others seem unaffected. Humans are now witnessing a mass extinction event, which provides ecologists an opportunity to study in real time how species differ in their responses to climate change and other stressors. Some may go extinct within our lifetimes; others won’t. This project builds on one of North America’s longest-running studies of insect populations by continuing data collection at five sites in the Sierra Nevada Mountains of Northern California. Encompassing more than 150 species of butterflies, the project will explore habitat use by both butterflies and caterpillars to better understand climate impacts on insect populations. Of particular interest is the role of extreme droughts, which are affecting the western United States with increasing frequency. Results from the project will inform our understanding of ongoing insect and pollinator declines. Scientists will engage the public through a novel forecasting website and by involvement of local school groups in activities, including the creation of larger-than-life biological models of common species.

This project extends nearly five decades of observations in a dynamic system that has played an important role in our understanding of insects in the Anthropocene. Previous work with this long-term data has suggested that the impacts of climate change (particularly warming and drying trends) might be as important as the effects of habitat loss and degradation through pesticide accumulation and other processes. In this project, researchers investigate the role of montane environments as refugia during periods of climatic upheaval. In addition to continuing core data collection (biweekly presence/absence surveys), new information will be gathered on trophic networks and the response of insect populations to shifting climatic conditions mediated through plant resources (nectar sources in particular). Multiple types of observational data will be integrated into a statistical modeling framework that emphasizes forecasting with climatic uncertainty, and which will be validated on an annual basis through real-time forecasts updated within and among field seasons. Outcomes from this project will include inter-disciplinary tools for prediction with heterogeneous data sources, as well as advances on ecological theories of animals interacting with topographic complexity while responding to novel climatic conditions.

Perspective paper in Science: How many genetic changes create new species?

Check out our recent opinion piece in Science where we argue that speciation often involves genetic differentiation at many loci (genes) across the genome. This likely occurs because the effects of natural selection can be coupled across statistically correlated genes, such that selection on one locus spills over to other correlated loci. Thus, one key to understanding the speciation process is understanding the processes by which genes and traits become coupled and cause a transition from polymorphism within a population to geographic variation to genome-wide differentiation and distinct species.