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This content will become publicly available on March 1, 2025

Title: “A comparison of thermal stress response between Drosophila melanogaster and Drosophila pseudoobscura reveals differences between species and sexes”
The environment is changing faster than anticipated due to climate change, making species more vulnerable to its impacts. The level of vulnerability of species is influenced by factors such as the degree and duration of exposure, as well as the physiological sensitivity of organisms to changes in their environments, which has been shown to vary among species, populations, and individuals. Here, we compared physiological changes in fecundity, critical thermal maximum (CTmax), respiratory quotient (RQ), and DNA damage in ovaries in response to temperature stress in two species of fruit fly, Drosophila melanogaster (25 vs. 29.5 °C) and Drosophila pseudoobscura (20.5 vs. 25 °C). The fecundity of D. melanogaster was more affected by high temperatures when exposed during egg through adult development, while D. pseudoobscura was most significantly affected when exposed to high temperatures exclusively during egg through pupal development. Additionally, D. melanogaster males exhibited a decrease of CTmax under high temperatures, while females showed an increase of CTmax when exposed to high temperatures during egg through adult development. while D. pseudoobscura females and males showed an increased CTmax only when reared at high temperatures during egg through pupae development. Moreover, both species showed an acceleration in oogenesis and an increase in apoptosis due to heat stress. These changes can likely be attributed to key differences in the geographic range, thermal range, development time, and other different factors between these two systems. Through this comparison of variation in physiology and developmental response to thermal stress, we found important differences between species and sexes that suggest future work needs to account for these factors separately in understanding the effects of constant increased temperatures.  more » « less
Award ID(s):
1751296
NSF-PAR ID:
10524491
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Insect Physiology
Volume:
153
Issue:
C
ISSN:
0022-1910
Page Range / eLocation ID:
104616
Subject(s) / Keyword(s):
Drosophila Climate change Fecundity Thermal tolerance Oogenesis
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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