Data from: Patterns of sperm swimming behaviour depend on male mating tactic and spawning environment in chinook salmon
Data files
Apr 03, 2025 version files 26.57 KB
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README.md
2.29 KB
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Rosengrave_et_al_data.csv
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Abstract
Many species exhibit alternative mating tactics (ARTs), with larger, socially dominant males competing for females and smaller males adopting “sneaker” strategies to exploit fertilisation opportunities without competition or courtship. Females typically prefer larger socially dominant males, but their ability to manipulate mating or fertilisation outcomes is largely unknown. Here, using chinook salmon Oncorhynchus tshawytscha, we ask whether the female’s ovarian fluid (OF) differentially influences the temporal patterns of sperm swimming in ejaculates from non-preferred sneaker (‘parr’) and preferred (dominant) males. We demonstrate that OF improves sperm swimming speed and linearity compared to river water, regardless of male mating tactic, but also report a novel tactic-specific difference in sperm linearity; parr male sperm initially maintain straighter trajectories in river water, compared to dominant males, but then rapidly change to less linear and more circular paths over time. Intriguingly, we show that OF counteracts this change in sperm linearity in parr males so that patterns become indistinguishable from dominants when parr sperm swim in OF. Together, these results lead us to predict that male chinook salmon exhibit differential sperm trait investment strategies that depend on reproductive tactic.
https://doi.org/10.5061/dryad.3tx95x6r6
Description of the data and file structure
Raw data
This file contains all of the raw data analysed for this paper.
Rosengrave_et_data.csv
This file explains all dataset variables accompanying Patterns of sperm swimming behaviour depending on male mating tactics and spawning environment in chinook salmon.
Dataset: Rosengrave_et_al_data.CSV
The file includes the following columns standard to the format:
Column Entry Unit Explanation
A Sample Unique ID for each CASA capture
B ID ID of milt subsample
C Male Focal male ID
D Tactic Alternative reproductive tactic of the focal male. H = large 2-year-old male, S = parr (sneaker) male
E Treatment Medium of sperm activation. RW = river water, OV = ovarian fluid
F Time seconds **Seconds Time in seconds post sperm activation
G **VAP Micrometres per second “CASA measure - average path velocity, i.e. sperm velocity along a smoothed path.”
H VSL Micrometres per second “CASA measure - straight-line velocity, i.e. velocity in a straght line form the start to end points of the sperm’s path.”
I VCL Micrometres per second “CASA measure - curvilinear velocity, i.e. sperm velocity along its swimming path.”
J ALH Micrometres CASA measure - amplitude of lateral head displacement about the sperm’s average path.
K BCF Hertz “CASA measure - beat cross frequency, i.e. average rate that curvilinlear path crosses average path.”
L STR Ratio “CASA measure - straightness, i.e. linearity of sperms average path (VSL/VAP).”
M LIN Ratio CASA measure - linearity of sperm’s curvilinear path (VSL/VCL)
N Motile Count the number of motile sperm captured via CASA
O Non motile Count the number of non-motile sperm captured vai CASA
P Total count Count total of the number of sperm captured via CASA
Statistical Supplement
The R code used for statistical analysis in this study is an R Markdown file.
Written by Rowan Lymbery.
Source Software R Environment for Statistical Computing. Version: 4.3.1.
R Markdwon file
Rosengrave_et_code.R.