Raw data for tetracycline treatment

Number of male and female adults appeared following tetracycline treatment

Sexual phenotype of offspring produced by tetracycline-treated CF females

Raw data for Fig. 3B

Gene dose of Ket and Tpi in CF adults that were treated with tetracycline during larval stages

Raw data for Fig. 4I

Gene dose of Ket in adult offspring produced by tetracycline-treated CF females

Raw data for Fig. 3C

Raw data of M. desjardinsi samples collected in Matsudo

Raw data of M. desjardinsi samples collected in Matsud

Mitochondrial haplotypes and Spiroplasma infection status of females collected in 2011 and 2016 from Rapid comeback of males: evolution of male-killer suppression in a green lacewing population

Evolutionary theory predicts that the spread of cytoplasmic sex ratio distorters leads to the evolution of host nuclear suppressors, although there are extremely few empirical observations of this phenomenon. Here, we demonstrate that a nuclear suppressor of a cytoplasmic male killer has spread rapidly in a population of the green lacewing <i>Mallada desjardinsi</i>. An <i>M. desjardinsi</i> population, which was strongly female-biased in 2011 because of a high prevalence of the male-killing <i>Spiroplasma</i> endosymbiont, had a sex ratio near parity in 2016, despite a consistent <i>Spiroplasma</i> prevalence. Most of the offspring derived from individuals collected in 2016 had 1 : 1 sex ratios in subsequent generations. Contrastingly, all-female or female-biased broods appeared frequently from crossings of these female offspring with males derived from a laboratory line founded by individuals collected in 2011. These results suggest near-fixation of a nuclear suppressor against male killing in 2016 and reject the notion that a non-male-killing <i>Spiroplasma</i> variant has spread in the population. Consistently, no significant difference was detected in mitochondrial haplotype variation between 2011 and 2016. These findings, and earlier findings in the butterfly <i>Hypolimnas bolina</i> in Samoa, suggest that these quick events of male recovery occur more commonly than is generally appreciated

Sex ratios of offspring produced by Spiroplasma-infected 2016 females crossed with 2011 males (outbred) or 2016 males (inbred) from Rapid comeback of males: evolution of male-killer suppression in a green lacewing population

Evolutionary theory predicts that the spread of cytoplasmic sex ratio distorters leads to the evolution of host nuclear suppressors, although there are extremely few empirical observations of this phenomenon. Here, we demonstrate that a nuclear suppressor of a cytoplasmic male killer has spread rapidly in a population of the green lacewing <i>Mallada desjardinsi</i>. An <i>M. desjardinsi</i> population, which was strongly female-biased in 2011 because of a high prevalence of the male-killing <i>Spiroplasma</i> endosymbiont, had a sex ratio near parity in 2016, despite a consistent <i>Spiroplasma</i> prevalence. Most of the offspring derived from individuals collected in 2016 had 1 : 1 sex ratios in subsequent generations. Contrastingly, all-female or female-biased broods appeared frequently from crossings of these female offspring with males derived from a laboratory line founded by individuals collected in 2011. These results suggest near-fixation of a nuclear suppressor against male killing in 2016 and reject the notion that a non-male-killing <i>Spiroplasma</i> variant has spread in the population. Consistently, no significant difference was detected in mitochondrial haplotype variation between 2011 and 2016. These findings, and earlier findings in the butterfly <i>Hypolimnas bolina</i> in Samoa, suggest that these quick events of male recovery occur more commonly than is generally appreciated

Infection status of females collected in 2011 and 2016, and sex ratios of their offspring from Rapid comeback of males: evolution of male-killer suppression in a green lacewing population

Evolutionary theory predicts that the spread of cytoplasmic sex ratio distorters leads to the evolution of host nuclear suppressors, although there are extremely few empirical observations of this phenomenon. Here, we demonstrate that a nuclear suppressor of a cytoplasmic male killer has spread rapidly in a population of the green lacewing <i>Mallada desjardinsi</i>. An <i>M. desjardinsi</i> population, which was strongly female-biased in 2011 because of a high prevalence of the male-killing <i>Spiroplasma</i> endosymbiont, had a sex ratio near parity in 2016, despite a consistent <i>Spiroplasma</i> prevalence. Most of the offspring derived from individuals collected in 2016 had 1 : 1 sex ratios in subsequent generations. Contrastingly, all-female or female-biased broods appeared frequently from crossings of these female offspring with males derived from a laboratory line founded by individuals collected in 2011. These results suggest near-fixation of a nuclear suppressor against male killing in 2016 and reject the notion that a non-male-killing <i>Spiroplasma</i> variant has spread in the population. Consistently, no significant difference was detected in mitochondrial haplotype variation between 2011 and 2016. These findings, and earlier findings in the butterfly <i>Hypolimnas bolina</i> in Samoa, suggest that these quick events of male recovery occur more commonly than is generally appreciated

Sexual versus Asexual Reproduction: Distinct Outcomes in Relative Abundance of Parthenogenetic Mealybugs following Recent Colonization

<div><p>Asexual reproduction, including parthenogenesis in which embryos develop within a female without fertilization, is assumed to confer advantages over sexual reproduction, which includes a “cost of males.” Sexual reproduction largely predominates in animals, however, indicating that this cost is outweighed by the genetic and/or ecological benefits of sexuality, including the acquisition of advantageous mutations occurring in different individuals and the elimination of deleterious mutations. But the evolution of sexual reproduction remains unclear, because we have limited examples that demonstrate the relative success of sexual lineages in the face of competition from asexual lineages in the same environment. Here we investigated a sympatric occurrence of sexual and asexual reproduction in the pineapple mealybug, <i>Dysmicoccus brevipes</i>. This pest invaded southwestern Japan, including Okinawa and Ishigaki Islands, in the 1930s in association with imported pineapple plants. Our recent censuses demonstrated that on Okinawa sexually reproducing individuals can coexist with and even dominate asexual individuals in the presence of habitat and resource competition, which is considered to be severe for this nearly immobile insect. Molecular phylogeny based on partial DNA sequences in the mitochondrial and nuclear genomes, as well as the endosymbiotic bacterial genome, revealed that the asexual lineage diverged from a common sexual ancestor in the relatively recent past. In contrast, only the asexual lineage exhibiting obligate apomictic thelytoky was discovered on Ishigaki. Co-existence of the two lineages cannot be explained by the results of laboratory experiments, which showed that the intrinsic rate of increase in the sexual lineage was not obviously superior to that of the asexual lineage. Differences in biotic and/or abiotic selective forces operating on the two islands might be the cause of this discrepancy. This biological system offers a unique opportunity to assess the relative success of sexual versus asexual lineages with an unusual morphology and life cycle.</p></div

Frequencies of sexual and asexual individuals of <i>Dysmicoccus brevipes</i> from Okinawa (a) and Ishigaki (b).

<p>Frequencies of sexual and asexual individuals of <i>Dysmicoccus brevipes</i> from Okinawa (a) and Ishigaki (b).</p