DOI: 10.5061/dryad.qrfj6q5j3
title: Data from: A test of Haldane’s rule in Neodiprion sawflies and implications for the evolution of postzygotic isolation in haplodiploids

description: Haldane’s rule—a pattern in which hybrid sterility or inviability is
 observed in the heterogametic sex of an interspecific cross—is one of the
 most widely obeyed rules in nature. Because inheritance patterns are
 similar for sex chromosomes and haplodiploid genomes, Haldane’s rule may
 apply to haplodiploid taxa, predicting that haploid male hybrids will
 evolve sterility or inviability before diploid female hybrids. However,
 there are several genetic and evolutionary mechanisms that may reduce the
 tendency of haplodiploids to obey Haldane’s rule. Currently, there are
 insufficient data from haplodiploids to determine how frequently they
 adhere to Haldane’s rule. To help fill this gap, we crossed a pair of
 haplodiploid hymenopteran species (Neodiprion lecontei and Neodiprion
 pinetum) and evaluated the viability and fertility of female and male
 hybrids. Despite considerable divergence, we found no evidence of reduced
 fertility in hybrids of either sex, consistent with the hypothesis that
 hybrid sterility evolves slowly in haplodiploids. For viability, we found
 a pattern opposite of Haldane’s rule: hybrid females, but not males, had
 reduced viability. This reduction was most pronounced in one direction of
 the cross, possibly due to a cytoplasmic-nuclear incompatibility. We also
 found evidence of extrinsic postzygotic isolation in hybrids of both
 sexes, raising the possibility that this form or reproductive isolation
 tends to emerge early in speciation in host-specialized insects. Our work
 emphasizes the need for more studies on reproductive isolation in
 haplodiploids, which are abundant in nature, but under-represented in the
 speciation literature.
description: Adult sex ratio data were collected from laboratory rearing logs
 from 2013-2017 during times when both species and hybrids were being
 reared in the lab. Hand-written data were transcribed into an excel file
 and checked for accuracy before analysis in R.  Embryo
 viability data were collected from laboratory rearing logs and
 experimental notebooks for an interspecific cross in which we recorded egg
 number and counted hatchlings 48 hours after hatching started.
 Hand-written data were transcribed into an excel file and checked for
 accuracy before analysis in R.  Female fertility data
 were collected from laboratory rearing logs and experimental notebooks in
 which we recorded whether or not eggs were laid and total egg number laid
 by pure-species and hybrid females. Hand-written data were transcribed
 into an excel file and checked for accuracy before analysis in
 R.   Male fertility data were recorded in experimental
 notebooks as sperm were observed under a microscope. These hand-written
 data were transcribed into an excel file and checked for accuracy before
 analysis in R. We also used laboratory rearing notebooks to verify that
 hybrid males produced viable female offspring.  Male
 behavioral sterility data were recorded in experimental notebooks during
 mating assays and then transcribed into an excel file and checked for
 accuracy before  analysis in R.
description: Missing values are indicated by "NA"
description: This Dryad repository contains all data and R commands to evaluate hybrid
 viability and fertility in Neodiprion sawflies, as described in: "A
 test of Haldane’s rule in Neodiprion sawflies and implications for the
 evolution of postzygotic isolation in haplodiploids." For questions,
 contact corresponding author: Catherine Linnen
 ([catherine.linnen@uky.edu](mailto:catherine.linnen@uky.edu)) DATAFILES:
 **Compiled_hybrid_viability_2022.csv**: sex ratio data from 6 different
 types of families. Column names are as follows: "Family": unique
 identifier for each individual family "male_emergence": number
 of adult males "female_emergence": number of adult females
 "cross_type": type of family or cross, as defined by the mother
 and father "total": total number of adults emerged
 "propFem": proportion of adults that were female
 "propMale": proportion of adults that were male
 **EmbryoViability-2022.csv**: Number of eggs that hatched or failed to
 hatch for families containing pure lecontei, F1 hybrid females, F2 hybrid
 males, pure pinetum, on white or jack pine. Column names are as follows:
 "Family": Unique family identifier "Cross_type": type
 of family or cross, as defined by the mother and father "Host":
 host plant chosen by the mother (J = jack pine; W=white pine)
 "Eggs": number of eggs laid by the female "EggsFall":
 number of eggs that got knocked off during counting "TotalEggs":
 total number of eggs after accounting for lost eggs "EggHatch":
 number of hatchlings after 48 hrs of hatching "EggFail": number
 of eggs that failed to hatch (TotalEggs - EggHatch) "PropHatch":
 Proportion of eggs that hatched "CrossHost": composite variable
 that combines cross type and host, mostly for plotting.
 **Mated_female_fertility.csv**: whether or not a female laid and number of
 eggs laid by different types of females (hybrids and pure species) Column
 names are as follows: "Cross": unique identifier for each female
 "Oviposited": presence (1) or absence (0) of oviposition
 "egg_number": if female laid, number of eggs laid
 "Female": type of female (lecontei, pinetum, or reciprocal
 hybrids) **Male_mating_success.csv**: Mating outcomes (yes/no) for
 lecontei and hybrid males paired with lecontei females. Column names as
 follows: "ID": unique identifier for each attempted cross
 "Female": colony ID for each female "Male": colony ID
 for each male "Mated": presence (1) or absence (0) of a mating
 event in a 2-hr assay "Type": type of male (hybrid or lecontei
 male) **SpermMotility.csv**: Approximate percentage of sperm bundles that
 were motile in sperm dissected from testes of different types of males.
 Column names as follows: "Male": unique identifier for each
 male; some of these correspond to same IDs in male mating success assays
 "MaleType": type of male (hybrid, lecontei, or pinetum)
 "Family": family/colony ID for each male "Date
 dissected":the day the testes dissection took place "emergence
 date": the date the male emerged from his cocoon
 "time_to_dissection": the number of days between emergence and
 dissection "mated": whether (1) or not (0) a male mated with a
 female prior to dissection "PercentMotilityTestis1": approximate
 (to the nearest 5%) percentage of sperm bundles that were moving for
 testis 1 (whichever testes was visualized first)
 "PercentMotilityTestis2": approximate (to the nearest 5%)
 percentage of sperm bundles that were moving for testis 2 (whichever
 testes was visualized second) "AvgMotilityTestes": average
 between two testes. R Scripts: **HR_in_Neodiprion_analyses_20Jan2023.R**:
 R code needed to produce all statistical results presented in the paper.
 Note all scripts were run using R v 4.2.1 and the following package
 versions: * car v3.1-0 * emmeans v1.8.0 - lmerTest v3.1-3 - ggplot2 v3.3.6
 - dplyr v1.0.9 - DescTools v0.99.45