DOI: 10.5061/dryad.g1jwstr08
title: Fertility loss and recovery dynamics after repeated heat stress across life stages in male Drosophila melanogaster: Patterns and processes

description: 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.
description: \#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.