DOI: 10.5061/dryad.tj57h
title: Data from: Asymmetrical sexual isolation but no postmating isolation between the closely related species Drosophila suboccidentalis and Drosophila occidentalis

description: Background: During the speciation process several types of isolating
 barriers can arise that limit gene flow between diverging populations.
 Studying recently isolated species can inform our understanding of how and
 when these barriers arise, and which barriers may be most important to
 limiting gene flow. Here we focus on Drosophila suboccidentalis and D.
 occidentalis, which are closely related mushroom-feeding species that
 inhabit western North America and are not known to overlap in geographic
 range. We investigate patterns of reproductive isolation between these
 species, including premating, postmating prezygotic, and postzygotic
 barriers to gene flow. Results: Using flies that originate from a single
 population of each species, we find that the strength of premating sexual
 isolation between these species is asymmetric: while D. occidentalis
 females mate with D. suboccidentalis males at a reduced but moderate rate,
 D. suboccidentalis females discriminate strongly against mating with D.
 occidentalis males. Female hybrids will mate at high rates with males of
 either species, indicating that this discrimination has a recessive
 genetic basis. Hybrid males are accepted by females of both species. We do
 not find evidence for postmating prezygotic or postzygotic isolating
 barriers, as females use the sperm of heterospecific males and both male
 and female hybrids are fully fertile. Conclusions: Premating isolation is
 substantial but incomplete, and appears to be the primary form of
 reproductive isolation between these species. If these species do
 hybridize, the lack of postzygotic barriers may allow for gene flow
 between them. Given that these species are recently diverged and are not
 known to be sympatric, the level of premating isolation is relatively
 strong given the lack of intrinsic postzygotic isolation. Further work is
 necessary to characterize the geographic and genetic variation in
 reproductive isolating barriers, as well as to determine the factors that
 drive reproductive isolation and the consequences that isolating barriers
 as well as geographic isolation have had on patterns of gene flow between
 these species.
description: Pure Species Mating
 RatesThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing pure species mating rates (Figure 1 from the
 paper). Each row represents a single pair of flies that were involved in a
 no-choice mate trial. A "1" in the "Mated(1=Yes)"
 column represents a pair of flies that successfully copulated within the
 allotted time frame. A "0" in this column indicated that the
 pair failed to copulate. The "Female_Species" column indicates
 the species of female in each pairing. The "Male_Species" column
 indicates the species of male in each pairing. "Suboccidentalis"
 refers to a pure Drosophila suboccidentalis individual.
 "Occidentalis" refers to a pure Drosophila occidentalis
 individual.Pure and Hybrid
 Female's Egg CountsThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing pure species female and hybrid individual female
 egg production (Figure 3 from the paper). Each row represents a single
 pair of flies. These flies were mated and the number of eggs produced by
 each female was tallied in the column titled "Egg_Count". The
 "Female_Type" column indicates whether the female fly in each
 pairing was a pure species individual or a hybrid individual. The
 "Male_Type" column indicates whether the male fly in each
 pairing was a pure species individual or a hybrid individual.
 "Suboccidentalis" refers to a pure species Drosophila
 suboccidentalis individual. "Occidentalis" refers to a pure
 species Drosophila occidentalis individual. "F1(OxS)" refers to
 a hybrid individual generated by crossing a Drosophila occidentalis female
 to a Drosophila suboccidentalis male. "F1(SxO)" refers to a
 hybrid individual generated by crossing a Drosophila suboccidentalis
 female to a Drosophila occidentalis male.Pure Species Offspring
 CountThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing pure species female and hybrid individual female
 progeny production (Figure 4 from the paper). Each row represents a single
 pair of flies. These flies were mated and the number resulting adult
 offspring produced was tallied in the column titled
 "Progeny_Count". The "Female_Species" column indicates
 the species of female in each pairing. The "Male_Species" column
 indicates the species of male in each pairing. "Suboccidentalis"
 refers to a pure species Drosophila suboccidentalis individual.
 "Occidentalis" refers to a pure species Drosophila occidentalis
 individual.Pure Species and Hybrid
 Male FertilityThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing pure species and hybrid individual female egg
 production (Figure 5 from the paper). Each row represents a set containing
 a single male fly and three female flies. These flies were mated and the
 number of progeny produced was tallied in the column titled
 "Progeny_Count". The "Female_Type" column indicates
 whether the female flies in each set was a pure species individual or a
 hybrid individual. The "Male_Type" column indicates whether the
 male fly in each set was a pure species individual or a hybrid individual.
 "Suboccidentalis" refers to a pure species Drosophila
 suboccidentalis individual. "Occidentalis" refers to a pure
 species Drosophila occidentalis individual. "Hybrid(OxS)" refers
 to a hybrid individual generated by crossing a Drosophila occidentalis
 female to a Drosophila suboccidentalis male. "Hybrid(SxO)"
 refers to a hybrid individual generated by crossing a Drosophila
 suboccidentalis female to a Drosophila occidentalis
 male.Male
 Fertility F1 Hybrids.txtPure Species Latency to
 MateThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing the latency to copulation between pure species
 individuals (Supplemental Figure 2). Each row represents a single pair of
 flies involved in a no-choice mate trial that successfully copulated
 within the allotted time frame. The latency to copulation (measured in
 minutes) for each pair is recorded in the column titled
 "Latency". The "Female_Species" column indicates the
 species of female in each pairing. The "Male_Species" column
 indicates the species of male in each pairing. "Suboccidentalis"
 refers to a pure Drosophila suboccidentalis individual.
 "Occidentalis" refers to a pure Drosophila occidentalis
 individual.Hybrid Individual Mating
 LatencyThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing the latency to copulation between pure species
 individuals (Supplemental Figure 3). Each row represents a single pair of
 flies involved in a no-choice mate trial that successfully copulated
 within the allotted time frame. The latency to copulation (measured in
 minutes) for each pair is recorded in the column titled
 "Latency". The "Female_Type" column indicates whether
 the female fly in each pairing was a pure species individual or a hybrid
 individual. The "Male_Type" column indicates whether the male
 fly in each pairing was a pure species individual or a hybrid individual.
 "Suboccidentalis" refers to a pure species Drosophila
 suboccidentalis individual. "Occidentalis" refers to a pure
 species Drosophila occidentalis individual. "Hybrid(OxS)" refers
 to a hybrid individual generated by crossing a Drosophila occidentalis
 female to a Drosophila suboccidentalis male. "Hybrid(SxO)"
 refers to a hybrid individual generated by crossing a Drosophila
 suboccidentalis female to a Drosophila occidentalis
 male.Hybrid
 Mating Latency.txtHybrid Mating
 RatesThis file contains data
 from the paper entitled "Asymmetrical sexual isolation but no
 postmating isolation between the closely related species Drosophila
 suboccidentalis and Drosophila occidentalis". This specific file
 contains data detailing mating rates between hybrid and pure species
 individuals (Figure 2 from the paper). Each row represents a single pair
 of flies that were involved in a no-choice mate trial. A "1" in
 the "Mated(1=Yes)" column represents a pair of flies that
 successfully copulated within the allotted time frame. A "0" in
 this column indicated that the pair failed to copulate. The
 "Female_Type" column indicates whether the female fly in each
 pairing was a pure species individual or a hybrid individual. The
 "Male_Type" column indicates whether the male fly in each
 pairing was a pure species individual or a hybrid individual.
 "Suboccidentalis" refers to a pure species Drosophila
 suboccidentalis individual. "Occidentalis" refers to a pure
 species Drosophila occidentalis individual. "Hybrid(OxS)" refers
 to a hybrid individual generated by crossing a Drosophila occidentalis
 female to a Drosophila suboccidentalis male. "Hybrid(SxO)"
 refers to a hybrid individual generated by crossing a Drosophila
 suboccidentalis female to a Drosophila occidentalis
 male.