Data from: Mating competition among females: testing the distinction between natural and sexual selection in an insect
Data files
Nov 04, 2024 version files 7.14 KB
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K-nartee-polyandry-data.csv
3.95 KB
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README.md
3.19 KB
Abstract
In species where females compete for mates, the male often provides the female with resources in addition to gametes. A recently suggested definition of sexual selection proposed that if females only benefit from additional resources that come with each mating and not additional gametes, female intrasexual competition for mating opportunities would result in natural selection rather than sexual selection. The nuptial gift-giving bushcricket Kawanaphila nartee has dynamic sex roles and has been a textbook example of sexual selection acting on females via mating competition. We investigated whether females of this species gain fitness benefits from nuptial gifts, additional ejaculates, or both, by controlling the number of matings and whether the female was allowed to consume the nutritious gift (spermatophylax) at mating. We found that egg production per day of life increased with the number of additional matings, both with and without spermatophylax consumption, but consuming the spermatophylax had an additional positive effect on the number of eggs. These effects were particularly strong in females with shorter lifespans. We discuss how the recently suggested definition of sexual selection applies to nuptial feeding insects, and conclude that both natural and sexual selection influence mating competition in K. nartee females.
This dataset is a part of the manuscript “Mating competition among females: testing the distinction between natural and sexual selection in an insect”, submitted in Royal Society Open Science.
The nuptial gift-giving bushcricket Kawanaphila nartee has dynamic sex roles and has been commonly used as an example of sexual selection acting on females via mating competition. However, a recently suggested definition of sexual selection proposed that if females only benefit from additional resources that come with each mating and not additional gametes, female intrasexual competition for mating opportunities would result in natural selection rather than sexual selection. In this study, we investigated whether females of this species gain fitness benefits from nuptial gifts, additional ejaculates, or both, by controlling the number of female matings and whether the female was allowed to consume the nutritious gift (spermatophylax) at mating.
FILES
Data file: K-nartee-polyandry-data.csv
R script file: K-nartee.R
VERSIONS AND SOFTWARE USED
R version 4.2.1 (2022-06-23)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS 14.3
attached base packages: parallel; stats; graphics; grDevices; utils; datasets; methods; base
other attached packages: ggplot2_3.4.4; MuMIn_1.47.5; car_3.1-2; carData_3.0-5; Rmisc_1.5.1; plyr_1.8.8; lattice_0.20-45; lme4_1.1-32; Matrix_1.5-3; emmeans_1.8.9; moments_0.14.1
VARIABLES IN THE DATA
Treatment: The main treatment effect.
‘single’: female was allowed to mate only once, and was allowed to consume the nuptial gift upon mating
‘spermgift’: female was allowed to mate multiple times, and was allowed to consume the nuptial gift upon each mating
‘spermonly’: female was allowed to mate multiple times, and was prevented from consuming the nuptial gift on the 2nd and 3rd mating
PronLength: pronotum length (mm)
Matings: Number of times the female mated in total (1-3)
TreatMate: Variable with six levels, combining the categories of treatment and number of matings. Used when creating figures.
Eggs: Total number of eggs produced in the females lifetime.
ViableEggs: Number of eggs estimated to be viable through the viability assay (where a maximum of 40 eggs were assayed)
InviableEggs: Number of eggs in the assay - number of viable eggs (ViableEggs)
AvEggWeight: Average egg weight (total egg weight divided by number of eggs, mg)
Lifespan: Days the female lived from the first mating until death
Days3rdMate: Number of days the female took to achieve a third mating, starting from the day she was introduced to males again after second mating. Only females that mated three times are included.
Days3rdMateAll: Number of days the female was exposed to a new male without mating a third time. Same as above, but includes individuals that mated twice and were alive at the end of mating trials but had not mated for a third time. These individuals got the ceiling date of 27th of October (the day the mating trials were ended), while the rest were calculated as in Days3rdMate.
Bushcrickets (Kawanaphila nartee) were collected from King's Park, Perth. Females were split into three treatments: a) ‘single mating’; b) multiple mating without spermatophylax: ‘sperm only’; and c) multiple mating with spermatophylax: ‘gift + sperm’. Females were allowed to continuously oviposit into a sand cup, and lifetime egg production was counted after the female perished naturally.