Statistical methods and data for: Absence of heterosis for hypoxia tolerance in F1 hybrids of Tigriopus californicus

This data set includes generalized structural equation models (SEM) for the parental populations and hybrid populations in Stata 18, code for figures in R and data in CSV format.  We used SEM over linear regression in order to also generate estimates of the errors and unexplained variance of the midpoint value of the parents.  First, we encoded sex, nuclear genome composition, collection cohort, days in lab after collection, and arena as variables in both models.  For the hybrid model, we also added terms for mitochondrial genome and interaction terms between sex and nuclear genome composition because we observed a different trend in sex differences for one population.  Separate SEM equations were necessary since parental populations were perfectly colinear with mitochondrial type, whereas F1 hybrids were not.  Since observations were grouped by arena and trial, we utilized a clustered standard error calculator when combining both models to allow for different variance between populatio..., Copepods were collected from four locations along the California coastline in December 2019 and August 2021 under collection permits S-192510001-19262-001 and S-192510001-21127-001. All copepods were then transported to the University of North Carolina at Chapel Hill where they were maintained for experiments.  Gravid females from each population were transferred to petri dishes with artificial sea water (ASW) and stored in a 12L:12D light cycle at 20°C for at least one month (equivalent to one generation) prior to testing.  Salinity was adjusted to 35 ppt, and ground commercial fish flakes, which served as food, were added ad libitum every other week. F1 hybrids were generated by placing virgin females of one population with virgin males from a second population. Copepods were grouped by sex and population then placed in aggregates of 5 into arenas of a water bath.  Temperature was maintained at 20°C by a cooling tower that circulated chilled water through the water bath, and the water..., , # Statistical methods and data for Absence of heterosis for hypoxia tolerance in F1 hybrids of Tigriopus californicus

[https://doi.org/10.5061/dryad.bk3j9kdn0](https://doi.org/10.5061/dryad.bk3j9kdn0)

## Description of the data and file structure

The data set includes experimental information (day, trial, pH, dissolved oxygen, temperature, time, etc.) and observations (alive, heteroplasmic or homoplasmic status) of *Tigriopus californicus* collected from hypoxia assays and genotyping.  Statistical analysis was performed in Stata 18, and the .do file for recreating the statistics.  For convenience, the data output file from the statistical analysis is also included.  Figures were generated in R, and an .rmd file containing the code for recreating the figures is included.

### Files and variables

#### File: Plasmy\_Hypoxia\_Tolerance\_-\_Sheet1.csv

**Description:** Data file of measurements and observations from hypoxia assays and genotype analysis.

##### Variables

* trial: Numeric...