Fertility loss and recovery dynamics after repeated heat stress across life stages in male Drosophila melanogaster: Patterns and processes
Data files
Jul 18, 2024 version files 394 KB
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Fitness_Assays.Rmd
17.14 KB
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FitnessAssay.csv
217.58 KB
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README.md
4.82 KB
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ReproductiveOrgan.csv
121.54 KB
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ReproductiveOrgan.Rmd
18 KB
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SpermViability.csv
7.74 KB
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SpermViability.Rmd
7.19 KB
Sep 12, 2024 version files 351.55 KB
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FitnessAssay.csv
217.58 KB
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README.md
4.69 KB
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ReproductiveOrgan.csv
121.54 KB
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SpermViability.csv
7.74 KB
Abstract
Frequent and extreme temperatures associated with climate change pose a major threat to biodiversity, particularly for organisms whose metabolism is strictly linked to ambient temperatures. Many studies have explored thermal effects on survival, but heat-induced fertility loss is emerging as a greater threat to population persistence. However, while evidence is accumulating both juvenile and adult stages heat exposure can impair fertility in their own ways, much less is known about the immediate and longer-term fitness consequences of repeated heat stress across life stages. To address this knowledge gap, we used male Drosophila melanogaster to investigate (i) the cumulative fitness effects of repeated heatwaves across life stages, (ii) the potential of recovery from these heat-exposed, and (iii) the underlying mechanisms. We found individual and combined effects of chronic juvenile and acute adult heat stress on male fitness traits. These effects tended to exacerbate over several days after brief heat exposure, indicating a substantial fertility loss for these short-lived organisms. Our findings highlight the cumulative and persistent effects of heat stress on fitness. Such combined effects could accelerate population declines, particularly in more vulnerable species, emphasizing the importance of considering reproduction and its recovery for more accurate models of species persistence.
README
#Fertility Loss and Recovery Dynamics After Repeated Heat Stress Across Life Stages in Male Drosophila melanogaster: Patterns and Processes
##Authors
Abhishek Meena, Alessio N. De Nardo, Komal Maggu, Sonja Sbilordo, Jeannine Roy, Rhonda R. Snook, Stefan Lüpold
##Overview
This dataset was collected to analyze fertility, fecundity, hatching success, seminal vesicle area, sperm presence/absence, accessory gland area, and sperm viability (dead and alive sperm) assays in male Drosophila melanogaster. The data is presented in three R Markdown (Rmd) files and three CSV files. The analyses focus on various factors influencing reproductive success under chronic developmental and 4 hours of acute adult temperature conditions.
##Contents
The dataset includes the following files:
Fitness_Assay.csv: This CSV file contains the raw data used in the Fitness_Assay.Rmd analysis.
ReproductiveOrgan.Rmd: This R Markdown file analyzes seminal vesicle area, sperm presence/absence, and accessory gland area using the ReproductiveOrgan.csv file.
ReproductiveOrgan.csv: This CSV file contains the raw data used in the ReproductiveOrgan.Rmd analysis.
SpermViability.Rmd: This R Markdown file analyzes sperm viability using the SpermViability.csv file.
SpermViability.csv: This CSV file contains the raw data used in the SpermViability.Rmd analysis.
#Data Description
Note: NA's in each data file represent missing data (data not available).
##FitnessAssay.csv
This file contains the following columns:
Line: ID's of isofemale lines based on the Drosophila Genetic Reference Panel (DGRP).
Heat tolerance (based on Zwoinska et al. 2020):
"High" = 15 High heat tolerance
"Low" = 14 Low heat tolerance
Developmental temperature: Males' rearing temperatures (24.5°C or 28°C).
Adult temperature: Temperature of 4-hour adult male exposure (24.5°C, 28°C, or 36.5 °C).
TotalEggs: Number of eggs laid by females after mating with focal males.
Hatched: Number of hatched eggs among those laid (see TotalEggs).
Unhatched: Number of unhatched eggs among those laid (see TotalEggs).
MaleID: Unique identifier for each focal male.
Day: Day after adult heat exposure.
Block: Experimental block.
ObservationID: Observation-level identifier to be used as an observation-level random effect.
#ReproductiveOrgan.csv
This file contains the following columns:
UniqueID: Observation-level identifier.
Block: Experimental block.
Day: Day after adult heat exposure.
Mating status: Mating history of dissected male (Mated or Virgin).
LeftAccessoryGlandArea: Left accessory gland area in mm2. (Note: Accessory gland is an organ secreting seminal fluid).
RightAccessoryGlandArea: Right accessory gland area in mm2.
AverageAccessoryGlandArea: (LeftAccessoryGlandArea + RightAccessoryGlandArea) / 2 (in mm2).
RightSeminalVesicleArea: Right seminal vesicle area in mm2. (Note: Seminal vesicle stores mature sperm until ejaculation).
LeftSeminalVesicleArea: Left seminal vesicle area in mm2.
AverageSeminalVesicleArea: (RightSeminalVesicleArea + LeftSeminalVesicleArea) / 2 (in mm2).
Thorax_4x: Length of male thorax, used as a proxy of body size (in mm), adjusted for magnification.
Line: ID's of isofemale lines based on the Drosophila Genetic Reference Panel (DGRP).
Sperm_Status: Indicates whether seminal vesicles contain mature sperm. "1" refers to sperm present, and "0" refers to sperm absent.
Heat tolerance (based on Zwoinska et al. 2020):
"High" = 5 High heat tolerance
"Low" = 5 Low heat tolerance
Developmental temperature: Males' rearing temperatures (24.5°C or 28°C).
Adult temperature: Temperature of 4-hour adult male exposure (24.5°C or 36.5 °C).
#SpermViability.csv
This file contains the following columns:
Line: ID's of isofemale lines based on the Drosophila Genetic Reference Panel (DGRP).
Day: Day after adult heat exposure.
Live.sperm: Number of live sperm in semen sample retrieved from seminal vesicles.
Dead.sperm: Number of dead sperm in semen sample retrieved from seminal vesicles.
TotalSperm: Number of live and dead sperms.
Developmental temperature: Males' rearing temperatures (24.5°C or 28°C).
Adult temperature: Temperature of 4-hour adult male exposure (24.5°C, 28°C, or 36.5 °C).
Heat tolerance (based on Zwoinska et al. 2020):
"High" = 5 High heat tolerance
"Low" = 5 Low heat tolerance
The dataset contains "null," which refers to no sperm found during the sperm viability assay.
Usage
To analyze the dataset, open and run the respective R Markdown (Rmd) files in RStudio or any compatible R Markdown environment. The Rmd files contain all the necessary code to reproduce the analyses described in the overview.