U.S. Department of Energy, Office of Science

Program for Ecosystem Research

Research Project   Reponses of a seasonal ectotherm (Allonemobius socius) to global warming

Principal investigator:   Wade E. Winterhalter

A. socius

The striped ground cricket Allonemobius socius (female [left], male [right]). The bar is 3 cm long.

Project goal

Understand how global warming might alter the geographic distribution of the striped ground cricket, Allonemobius socius, in the eastern United States.

Ecosystem being studied

The project is studying populations of the cricket A. socius collected at multiple locations in the eastern United States (northern and southern Ohio, western West Virginia, southern Virginia, and eastern Georgia). Collections were made from the northern (cool), transitional, and southern (warm) zones of the species' present geographic range in the United States.


The A. socius populations have been collected from the field and the laboratory warming experiments are underway. It is expected that the project will be able to (1) predict the optimal life-history strategies of several A. socius populations; (2) test these predictions and evaluate the populations' responses to warming in the laboratory; and (3) determine how these responses might affect the geographoc distribution of A. socius in the future.

Why this is important

An understanding of how, and why, climatic change might affect ecosystems and organisms in the future will depend in part on accurate information about how global warming could affect biological species. This project represents one of the most robust examinations of this issue to date, and it is expected that results from the study species (A. socius) will provide important insights into the possible effects of warming on other ectotherms.

The project provides a critical link between climatological and biological datasets and, it is hoped, will encourage future collaborations between these two historically dissociated fields. Additionally, it is expected that a rigorous empirical examination of a species' potential response to global warming, based on specific quantitative hypotheses such as those posed by this project, will be of interest not only to biologists and climatologists, but also to the general public.


Three general research activities are being carried out. In the first, projections of temperature changes (warming) during the next 100 years, made by a coupled atmosphere-ocean general circulation model, are being linked to an empirically confirmed theoretical model that describes the optimal life-history strategy of A. socius.

In the second activity, quantitative hypotheses developed in the first activity are being tested by rearing populations of A. socius in laboratory controlled-environment chambers that will simulate the seasonally fluctuating thermal and photoperiod conditions these crickets may experience in the future. These laboratory reared populations will provide an opportunity to evaluate how a species will respond to global warming. Specifically, the project will examine the buffering, acclimation, adaptation, migratory/competition, and extinction responses of the study populations. Special emphasis is given to populations collected at the northern (cool) and southern (warm) extremes of the species' present geographic distribution.

In the third activity, the various responses to warming will be synthesized so that specific years in which a population's response to a specified future global warming trajectory will change can be identified. From this synthesis, changes in A. socius' future geographic distribution will be estimated. The goal will then be to refine and generalize the warming-scenario-based biological model for A. socius so that the potential effects of warming on other species can be anticipated as well.


Wade E. Winterhalter, University of Central Florida

Kenneth M. Fedorka, University of Central Florida

Kerry Shaw, Cornell University (subaward)

Funding period:   August 2007 to present