DOI: 10.5061/dryad.d7wm37qc3
title: Data from: A single episode of sexual reproduction can produce large variation in population growth rates under dual stressors

description: Sexual reproduction has been a central topic in evolutionary biology
 because of its many costs: why did organisms evolve sexual reproduction
 despite the many costs of sex? To answer the question, researchers have
 conducted laboratory experiments to measure population growth rates with
 and without sexual reproduction under a stressor. Here we show that a
 single episode of sexual reproduction can produce a large amount of
 variation in population growth rates under dual stressors by laboratory
 experiments of a green alga, Closterium
 peracerosum–strigosum–littorale complex. We observed population dynamics
 of the alga under dual stressors and confirmed that high salinity and low
 pH decreased growth rates. By comparing parental and their hybrid F1
 populations, we observed larger variation in growth rates of F1
 populations (i.e., transgressive segregation) when pH was low.
 Interestingly, even when parental populations had negative growth rates,
 some F1 populations showed positive growth rates in severe environmental
 conditions due to the large variation in population growth. By utilizing
 the recently obtained genomic information of the alga, we conducted a gene
 ontology (GO) enrichment analysis and found that genes with copy number
 variations between parental strains were more frequently associated with
 pH stress-related terms than salt stress-related terms. Our results
 suggest that recombination and variation in the number of gene copies
 might produce large genetic variation in the F1 generation. This will be
 an important step toward a better understanding of the evolution of sex
 and evolutionary rescue where rapid contemporary evolution prevents
 population extinction in changing environments.
description: # Data from: A single episode of sexual reproduction can produce large
 variation in population growth rates under dual stressors
 [https://doi.org/10.5061/dryad.jq2bvq8m9](https://doi.org/10.5061/dryad.jq2bvq8m9) ## Description of the data and file structure Growth rate data and an analysis script for Closterium psl. complex under multiple stressors ### Files and variables #### File: All\_absorbance.csv **Description**: Biomass data for each population under different conditions. **Variable:** * Population: Population names (NIES-64, NIES-65, F1-A, F1-B, F1-C, F1-D, F1-E, F1-F, F1-G or F1-H) * pH: pH scales of medium conditions * NaCl: NaCl concentration of medium conditions * Day: Cultivation date * Replicate: Replication number * Absorbance: An absorbance of 684 nm * Zygospore: Number of zygospores from which each F1 population germinated * Category: Population categories (NIES-64, NIES-65 or F1) #### File: GrowthRate.csv **Description**: Growth rate data modeled non-linear least-squares fitting **Variable:** * Population: Population names (NIES-64, NIES-65, F1-A, F1-B, F1-C, F1-D, F1-E, F1-F, F1-G or F1-H) * pH: pH scales of medium conditions * NaCl: NaCl concentration of medium conditions * Replicate: Replication number * GrowthRate: Growth rate modeled using nonlinear least-squares fitting * Category: Population categories (NIES-64, NIES-65 or F1) * Zygospore: Number of zygospores from which each F1 population germinated Missing data code: NA #### File: Rscript.R **Description:** An analysis script for calculating growth rates, simulating F1 growth rates from parental ones, and performing Gene Ontology (GO) enrichment analysis. #### File: NIES65\_GOterm.Rdata **Description:** An RData file containing GO terms for NIES-65 peptides. #### File: NIES-6465\_CNVpattern.csv **Description:** A list of genes showing copy number variations between NIES-64 and NIES-65. **Variable:** * OrthologGroup_ID: Ortholog group ID by sonicparanoid * NIES64_gene: Gene ID from NIES-64 strain * NIES64_copy: Copy number of the gene from NIES-64 strain * NIES65_gene: Gene ID from NIES-65 strain * NIES65_copy: Copy number of the gene from NIES-65 strain * CNV: Copy number variation patterns of NIES-64 and NIES-65 #### File: CellCount\_Absorbance.csv **Description:** This file contains the relationship between cell count and absorbance (OD) measurements. **Variable:** * CellCount: Number of cells by eye under a microscope * Absorbance: An absorbance of 684 nm ## Access information Data was derived from the following sources: * NCBI BioProject: PRJEB57781