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Data associated with Hadlow et al. (2022) Density-dependent patterns of multivariate selection on sperm motility and morphology in a broadcast spawning mussel. Ecology and Evolution

Corresponding author contact information:
Jessica H. Hadlow
jessica.hadlow@research.uwa.edu.au
Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, M092 Perth WA 6009 Australia

Data were collected in June-October 2019 in Perth, Western Australia. The model species is Mytilus galloprovincialis, a marine broadcast spawning
mussel.
Details of data collection can be found in associated paper (published in Ecology and Evolution).
Sperm morphology was measured using Image J (v 1.48) and images taken of sperm fixed in 10% buffered formalin.
Sperm motility was analysed using computer-assisted sperm analysis (CASA, CEROS-II, Hamilton-Thorne, Beverly, USA).
Fertilisation rates were estimated as the number of embryos undergoing normal cleavage or with polar bodies out of 200 haphazardly-sampled eggs. Fertilisation assays were conducted
under two sperm density regimes (high and low sperm concentrations).
Data were analysed using multivariate selection analyses in R (v 3.6.0).

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File descriptions

Hadlow_2022_Density_dependent_selection_sperm_morphology_traits.csv

File containing sperm morphology measurements for 183 male mussels.
Morphology measurements were used as phenotypic predictors of fertilisation success.
Average sperm morphological traits taken from 20 sperm per male.
**  parameter not used in final analyses

ID: unique individual identifier for males. Letter at end of ID indicates treatment (H - high or L - low)
HW AVE**: average sperm head width (micrometres, um)
AC AVE**: average sperm acrosome length (um)
HL AVE: average sperm head length (um)
FL AVE: average sperm flagellum length (um)
TL AVE**: average total length of sperm (um)

Morphological data could not be collected for males 2012L and 2010H. The rows associated with these males contain "n/a" (rows 168 and 171).


Hadlow_2022_Density_dependent_selection_sperm_motility_and_fertilisation_rates.csv

File containing sperm motility parameters and fertilisation rates for 182 male mussels.
Motility measurements were used as phenotypic predictors of fertilisation success.
Fertilisation success used as a measure of reproductive fitness.
**  parameter not used in final analyses

ID: unique individual identifier for males. Letter at end of ID indicates treatment (H - high or L - low)
Block: number identifying experimental block to which the individual belongs (experiment was conducted in 22 blocks)
Treatment: H or L. H = high sperm density treatment, L = low sperm density treatment
Fert: fertilisation success, number of embryos undergoing normal cleavage or with polar bodies out of 200 haphazardly-sampled eggs
motilecount**: number of motile sperm tracked in the sample
ALH**: amplitude of lateral head placement, maximum lateral placement of sperm head about its average path (um)
BCF: beat-cross frequency, average rate at which the actual sperm trajectory crosses the average path (Hz)
LIN: path linearity, linearity of the curvilinear/actual sperm trajectory (VSL/VCL x 100)
STR**: path straightness, linearity of the average path (VSL/VAP x 100)
VAP**: average path velocity, average velocity of sperm along a smoothed track (um/s)
VCL: curvilinear velocity, average velocity of sperm measured along the actual track (um/s)
VSL**: stragiht-line velocity, average velocity of sperm along a straight line from their first and last detection point (um/s)
PM: percentage of motile sperm in the sample (%)
totalcount**: total number of sperm tracked in the sample (motile and non-motile)