Directional dominance is a prerequisite of inbreeding depression. Directionality arises when selection drives alleles that increase fitness to fixation and eliminates dominant deleterious alleles, while deleterious recessives are hidden from it and maintained at low frequencies. Traits under directional selection (i.e., fitness traits) are expected to show directional dominance and therefore an increased susceptibility to inbreeding depression. In contrast, traits under stabilizing selection or weakly linked to fitness are predicted to exhibit little-to-no inbreeding depression. Here, we quantify the extent of inbreeding depression in a range of male reproductive characters and then infer the mode of past selection on them. The use of transgenic populations of Drosophila melanogaster with red or green fluorescent-tagged sperm heads permitted in vivo discrimination of sperm from competing males and quantification of characteristics of ejaculate composition, performance, and fate. We found that male attractiveness (mating latency) and competitive fertilization success (P2) both show some inbreeding depression, suggesting they may have been under directional selection, whereas sperm length showed no inbreeding depression suggesting a history of stabilizing selection. However, despite having measured several sperm quality and quantity traits, our data did not allow us to discern the mechanism underlying the lowered competitive fertilization success of inbred (f = 0.50) males.
P2 data
Data for P2 analysis, and for offspring production before and after remating in the P2 experiment. Column abbreviations: id = female id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Fthorax = female thorax lentgh,
M2thorax = 2nd male thorax lentgh, P2day = day to which P2 value refers to, gl = number of first male's offspring, ngl = number of second male's offspring, totpriroprog= number of offspring produced before second mating, P2 = P2 (proportion), totremoffspring = number of offspring produced after second mating, asp2 = acrsin sqrt transformed P2 value
datap2.txt
copulation-duration-with-virgin
Copulation durations with virgin females in single-mating-productivity experiment. Column abbreviations: trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Femaleth = female thorax lentgh, Maleth = male thorax lentgh, Matlat = mating latency (min), copdur = copulation duration
Copulation duration with non-virgin
Copulation durations with non-virgins in the P2 expriment. Column abbreviations: id = female id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25),line = the line male originated from, Fthorax = female thorax lentgh, M2thorax = 2nd male thorax lentgh, remday = remating day, copdur2 = duration of the second copulation
2ndcopulationduration.txt
mating latency (male attractiveness)
Mating latencies with virgins in the single-mating-productivity experiment. Column abbreviations: trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Femaleth = female thorax lentgh, Maleth = male thorax lentgh, Matlat = mating latency (min), copdur = copulation duration
mating-latency.txt
remating day
Remating days in the P2 experiment. Column abbreviations: id = female id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25),line = the line male originated from, Fthorax = female thorax lentgh, M2thorax = 2nd male thorax lentgh, remday = remating day, copdur2 = duration of the second copulation
rematingday.txt
single-mating-productivity
Offspring production during ten days after single mating. Column abbreviations: trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Maleth = male thorax lentgh, Femaleth = female thorax lentgh, Mfamoforig = Male line of origin (within treatment), progeny = number of eclosed offspring, fday = day as a factor
spermcounts 60min after 2nd copulation started
Sperm counts in 60 min ASM treatment. Column abbreviations: ID = female id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Fthorax = female thorax lentgh, M2thorax = 2nd male thorax lentgh, bursagr = 1st male sperm in bursa, bursared = 2nd male sperm in bursa, prSRgr = 1st male sperm in proximal SR (seminal receptacle), prSRred = 2nd male sperm in proximal SR, distSRgr = 1st male sperm in distal SR, distSRgr = 2nd male sperm in distal SR, SPT1gr = 1st male sperm in spermatheca (SPT) 1, SPT1red = 2nd male sperm in spermatheca 1, SPT2gr = 1st male sperm in spermatheca 2, SPT2red = 2nd male sperm in spermatheca 2, duct1gr = 1st male sperm in spermathecal duct 1, duct1red = 2nd male sperm in spermathecal duct 1, duct2gr = 1st male sperm in spermathecal duct 2, duct2red = 2nd male sperm in spermathecal duct 2, SRtotred = 2nd male sperm in SR, TOTred = total number of 2nd male sperm, SPTtotred = total number of 2nd male sperm in SPT, STOREDred =total number of 2nd male sperm in SR and SPT, remday = remating day, copdur = copulation duration, totgr = total number of first male sperm
spermcounts60min.txt
sperm counts 5h after 2nd copulation started
Sperm counts from 5 h ASM treatment. Column abbreviations: ID = female id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Fthorax = female thorax lentgh, M2thorax = 2nd male thorax lentgh, bursagr = 1st male sperm in bursa, bursared = 2nd male sperm in bursa, prSRgr = 1st male sperm in proximal SR (seminal receptacle), prSRred = 2nd male sperm in proximal SR, distSRgr = 1st male sperm in distal SR, distSRgr = 2nd male sperm in distal SR, SPT1gr = 1st male sperm in spermatheca (SPT) 1, SPT1red = 2nd male sperm in spermatheca 1, SPT2gr = 1st male sperm in spermatheca 2, SPT2red = 2nd male sperm in spermatheca 2, duct1gr = 1st male sperm in spermathecal duct 1, duct1red = 2nd male sperm in spermathecal duct 1, duct2gr = 1st male sperm in spermathecal duct 2, duct2red = 2nd male sperm in spermathecal duct 2, SRtotred = 2nd male sperm in SR, TOTred = total number of 2nd male sperm, SPTtotred = total number of 2nd male sperm in SPT, STOREDred =total number of 2nd male sperm in SR and SPT, remday = remating day, copdur = copulation duration, totgr = total number of first male sperm, S2SR = proportion of second male sperm in SR, asS2= acrsin sqrt transformed S2 value
spermcounts5h.txt
sperm counts 6 days after 2nd copulation
Sperm counts from the 6 day ASM treatment. Column abbreviations: ID = female id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Fthorax = female thorax lentgh, M2thorax = 2nd male thorax lentgh, bursagr = 1st male sperm in bursa, bursared = 2nd male sperm in bursa, prSRgr = 1st male sperm in proximal SR (seminal receptacle), prSRred = 2nd male sperm in proximal SR, distSRgr = 1st male sperm in distal SR, distSRgr = 2nd male sperm in distal SR, SPT1gr = 1st male sperm in spermatheca (SPT) 1, SPT1red = 2nd male sperm in spermatheca 1, SPT2gr = 1st male sperm in spermatheca 2, SPT2red = 2nd male sperm in spermatheca 2, duct1gr = 1st male sperm in spermathecal duct 1, duct1red = 2nd male sperm in spermathecal duct 1, duct2gr = 1st male sperm in spermathecal duct 2, duct2red = 2nd male sperm in spermathecal duct 2, SRtotred = 2nd male sperm in SR, TOTred = total number of 2nd male sperm, SPTtotred = total number of 2nd male sperm in SPT, STOREDred =total number of 2nd male sperm in SR and SPT, remday = remating day, copdur = copulation duration, totgr = total number of first male sperm, logGR = log transformed 1st male sperm, S2 = proportion of second male sperm in SR, asS2= acrsin sqrt transformed S2 value, S2spt = proportion of second male sperm in SPT
spermcounts6days.txt
sperm length data
Sperm lengths in different inbreeding levels. Column abbreviations: trt = treatment: ob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25),male = male id, line = the line male originated from, (within treatment), Thorax = male thorax lentgh, Slentgh = sperm lentgh (mm)
spermlentgh.txt
sperm velocity
Sperm velocity in different male inbreeding levels. Column abbreviations: id = male id, trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Track = individual sperm followed for ten frames, velocity = sperm velocity, spermcount = number of sperm in seminal receptacle, Fthorax = female thorax lentgh, Mthorax = male thorax lentgh, correctedvelocity = velocity in microm/s, locvel = log-transformed correctedvelocity
spermvelocity.txt
egg-to-adut viability
Egg-to-adult viability on days 1, 3 and 5 in the single-mating-productivity experiment. Column abbreviations: trt = treatment: aob = outbred (f =0), ib = highly inbred (f = 0.5), sib = moderately inbred (f = 0.25), Maleth = male thorax lentgh, Femaleth = female thorax lentgh, viab = viability, fday = day as a factor
viability.txt