DOI: 10.5061/dryad.gh2pb
title: Data from: Chromosome-wide impacts on the expression of incompatibilities in hybrids of Tigriopus californicus

description: Chromosome rearrangements such as inversions have been recognized
 previously as contributing to reproductive isolation by maintaining
 alleles together that jointly contribute to deleterious genetic
 interactions and postzygotic reproductive isolation. In this study an
 impact of potential incompatibilities merely residing on the same
 chromosome is found in crosses of populations of the copepod Tigriopus
 californicus. When genetically divergent populations of this copepod are
 crossed, hybrids show reduced fitness and deviations from expected
 genotypic ratios can be used to determine regions of the genome involved
 in deleterious interactions. In this study a set of markers is genotyped
 for a cross of two populations of T. californicus and these markers show
 widespread deviations from Mendelian expectations with entire chromosomes
 showing marked skew. Despite the importance of mtDNA/nuclear interactions
 in incompatibilities in this system in previous studies, in these crosses
 the expected patterns stemming from these interactions are not widely
 apparent. Females lack recombination in this species and a striking
 difference is observed between male and female backcrosses. This suggests
 that the maintenance of multiple loci on individual chromosomes can enable
 some incompatibilities, perhaps playing a similar role in the initial
 rounds of hybridization to chromosomal rearrangements in preserving sets
 of alleles together that contribute to incompatibilities. Finally, it is
 observed that candidate pairs of incompatibility regions are not
 consistently interacting across replicates or subsets of these crosses
 despite the repeatability of the deviations at many of the single loci
 themselves, suggesting that more complicated models of Dobzhansky-Muller
 incompatibilities may need to be considered.
description: Genotyping data from DA1
 adultsThis spreadsheet has the
 genotyping results from 25 loci for crosses between SD females and AB
 males. Genotypes are as follows: (S-SD homozygote, SB-heterozygote, B-AB
 homozygote). Headers for columns are in order: sample-unique sample number
 for each copepod; date-date of 96 well collection plate; ID-identity of
 subset of F2 adults; plate-additional plate from same ID line denoted with
 b (or c); sex-male or female adult; TEMP-temperature environment in which
 F2 individual developed; GDHad_1-marker name (subsequent columns are the
 additional 24 markers).DAadult_score2_10fadded.csvGenotyping data from AD1 adultsThis spreadsheet has the genotyping results from 25 loci for crosses between SD females and AB males. Genotypes are as follows: (S-SD homozygote, SB-heterozygote, B-AB homozygote). Headers for columns are in order: sample-unique sample number for each copepod; date-date identifier for copepod; plate-plate identifier for 96 well plate; ID-identity of subset of F2 adults; sex-male or female adult; TEMP-temperature environment in which F2 individual developed; GDHad_1-marker name (subsequent columns are the additional 24 markers).AD_join_score3_3_15.csvGenotyping data from DA1 F2 naupliiThis spreadsheet has the genotyping results from 25 loci for crosses between SD females and AB males. Genotypes are as follows: (S-SD homozygote, SB-heterozygote, B-AB homozygote). Headers for columns are in order: sample-unique sample number for each copepod; date-date identifier for copepod collection; ID-identity female from which eggsac was obtained; sex-N for nauplii TEMP-temperature environment in which F2 individual developed (all 20 degrees for this set); GDHad_1-marker name (subsequent columns are the additional 24 markers).DAnaup_score2.csvR code for analyzing 2-way and 3-way interactionsThis code was used to compute chi-square values for all 2-way and 3-way interactions between the loci included in the analysis.DAadult_source_code_update.RMale/female contingency table R codeThis R code calculates the contingency tables for genotypic results for males versus females.mf_contingency_calcsR.R