The effect of temperature on development time and body size in male and female wild-type Oregon-R and mutant ort-1 Drosophila melanogaster

Abstract

The purpose of this study was to examine the effects of differing temperatures on average development time and body size in male and female, wild-type Oregon-R, and mutant, ort-1, Drosophila melanogaster. D. melanogaster were raised from larval to adult stage in three temperature treatments, 17˚C, 25˚C and 30˚C, each containing five replicates. Body size was measured for the adult flies, and date of emergence and gender were recorded. The presence of the mutation at the different temperatures showed no significant difference in both average body size and development time (with a two-way ANOVA, p=0.60; p=0.24; between 17˚C and 25˚C). However, when examining individuals based on fly type, there was a significant difference in average development time for D. melanogaster between 17˚C and 25˚C (p<0.0001). Through a comparison of the means, the same trend was present between 17˚C and 30˚C, but absent between 25˚C and 30˚C. Average body size was not affected by temperature in the analysis on fly type (p=0.89). The effects of temperature on average body size (p=0.90) and development time (p=0.74) was the same between genders, however, gender did exhibit an effect on average body size (p=0.0004). Additionally, average development time within males and within females was significantly longer at 17˚C compared to 25˚C (males and females: p<0.0001) and 30˚C (males and females: p<0.0001). Temperature had an effect on average body size and development time of D. melanogaster when grouping individuals by gender (p=0.016; p<0.0001, respectively). Additionally, the effects of temperature on average development time and body size was the same between fly types (p=0.24; p=0.60, respectively) and between genders (p=0.79; p=0.90, respectively). As such, we failed to support that gender affected average development time, the mutation affected average body size or average development time, or there being a differential effect of temperature between wild-type and mutant, and males and females on average body size and average development time.