Difference in cold tolerance of Drosophila melanogaster in Vermont and Chiapas
Conference Year
January 2019
Abstract
Temperature has had profound effects on the physiology, ecology, and fitness of small ectotherms, such as Drosophila melanogaster, which cannot endogenously regulate body temperature within a physiological broad range. In the context of climate change, alterations in seasonality and irregularities in temperature have introduced these vulnerable organisms to unforeseeable thermal environments to which they are not well adapted. Moreover, populations from different geographic regions within the D. melanogaster species may differ in their ability to cope with these extreme changes. We hypothesized that Vermont and Chiapas larvae would have different cold tolerance temperatures and we predicted that Vermont larvae would tolerate colder temperatures relative to Chiapas flies. Two populations were collected from East Calais, VT and Chiapas, Mexico. Vials were prepared separately and contained 50-100 larvae. The cold tolerance of larvae was assayed by scoring the amount of flies that survived after exposure to a 45-minute cold treatment across a range of temperatures, from 14°C to 5°C. We measured cold tolerance at the temperature at which half of the larvae did not recover from cold stress with a least-squares regression model. The importance of our results shows how climate change could threaten the extinction of many ectothermic species, unless populations can evolutionarily adapt to extreme temperatures from different geographic locations with varying temperatures.
Primary Faculty Mentor Name
Dr. Brent Lockwood
Secondary Mentor Name
Emily Mikucki
Graduate Student Mentors
Emily Mikucki
Faculty/Staff Collaborators
Emily Mikucki (Graduate Student Mentor)
Status
Undergraduate
Student College
College of Arts and Sciences
Program/Major
Biological Sciences, Integrated
Primary Research Category
Arts & Humanities
Secondary Research Category
Biological Sciences
Difference in cold tolerance of Drosophila melanogaster in Vermont and Chiapas
Temperature has had profound effects on the physiology, ecology, and fitness of small ectotherms, such as Drosophila melanogaster, which cannot endogenously regulate body temperature within a physiological broad range. In the context of climate change, alterations in seasonality and irregularities in temperature have introduced these vulnerable organisms to unforeseeable thermal environments to which they are not well adapted. Moreover, populations from different geographic regions within the D. melanogaster species may differ in their ability to cope with these extreme changes. We hypothesized that Vermont and Chiapas larvae would have different cold tolerance temperatures and we predicted that Vermont larvae would tolerate colder temperatures relative to Chiapas flies. Two populations were collected from East Calais, VT and Chiapas, Mexico. Vials were prepared separately and contained 50-100 larvae. The cold tolerance of larvae was assayed by scoring the amount of flies that survived after exposure to a 45-minute cold treatment across a range of temperatures, from 14°C to 5°C. We measured cold tolerance at the temperature at which half of the larvae did not recover from cold stress with a least-squares regression model. The importance of our results shows how climate change could threaten the extinction of many ectothermic species, unless populations can evolutionarily adapt to extreme temperatures from different geographic locations with varying temperatures.