Conflicting constraints on male mating success shape reward size in pollen-rewarding plants.

PREMISE: Pollen-rewarding plants face two conflicting constraints: They must prevent consumptive emasculation while remaining attractive to pollen-collecting visitors. Small pollen packages (the quantity of pollen available in a single visit) may discourage visitors from grooming (reducing consumptive loss) but may also decrease a plant's attractiveness to pollen-collecting visitors. What package size best balances these two constraints? METHODS: We modeled the joint effects of pollinators' grooming behaviors and package size preferences on the optimal package size (i.e., the size that maximizes pollen donation). We then used this model to examine Darwin's conjecture that selection should favor increased pollen production in pollen-rewarding plants. RESULTS: When package size preferences are weak, minimizing package size reduces grooming losses and should be favored (as in previous theoretical studies). Stronger preferences select for larger packages despite the associated increase to grooming loss because loss associated with nonremoval of smaller packages is even greater. Total pollen donation increases with production (as Darwin suggested). However, if floral visitation declines or packages size preference increases with overall pollen availability, the fraction of pollen donated may decline as per-plant pollen production increases. Hence, increasing production may result in diminishing returns. CONCLUSIONS: Pollen-rewarding plants can balance conflicting constraints on pollen donation by producing intermediate-sized pollen packages. Strictly pollen-rewarding plants may have responded to past selection to produce more pollen in total, but diminishing returns may limit the strength of that selection.

Alternative reproductive tactics in goby fishes of the Caspian Sea.

Here we report on the reproductive morphology and histology of three Gobiidae species (the Caspian monkey goby, Neogobius pallasi; the Caspian goby, Neogobius caspius; and the round goby, Neogobius melanostomus) from the Iranian coastline of the Caspian Sea. Based on ageing, reproductive histology, and internal and external morphological measures, it appears that all three of these goby species have two types of reproductive males, a large courting, territorial, male type and a small cuckolding parasitic male type, a phenomenon known as alternative reproductive tactics (ART). Although ARTs have been reported previously for one of these species, the round goby, all reports stem from its invasive range; ARTs have never been reported before in any fish species in the Caspian Sea. In all three goby species there was a large, older male type, with a wide head, dark body colouration, and a large investment in accessory glands (AG), an organ important for female attraction and parental care. But there was also a small, light, younger male type, with a narrow head, longer urogenital papilla, and little investment in AGs. The Caspian goby were the largest of the three species, and in this species the smaller, lighter, presumably cuckolding male morph was quite rare (only about 5% of the reproductive male population). In contrast, many of the round goby and monkey goby males were the small, lighter parasitic type, making up nearly half the population of reproductive males (48% and 40%, respectively). Round goby and Caspian goby males had a prominent mesorchial gland, a fibrous sheath of pheromone-releasing connective tissue that attaches the testes to the dorsal body wall, but all the monkey goby specimens examined lacked this structure. Although ARTs are well documented across fish species and appear to be particularly common in gobies, our study provides the first evidence for ARTs in goby fishes from the Caspian Sea.

Male mating choices: The drive behind menopause?

When we examine the life history of humans against our closest primate relatives, the other great apes, there is notably a greater longevity in humans which includes a distinctive postmenopausal life stage, leading to the question, "How did human females evolve to have old-age infertility?" In their paper "Mate choice and the origin of menopause" (Morton et al., 2013), Morton et al. developed an agent-based model (ABM) to investigate the novel hypothesis that ancestral male mating choices, particularly forgoing mating with older females, were the driving force behind the evolution of menopause. From their model, they concluded that indeed male preference for young female mates could have driven females to lose fertility at older ages through deleterious mutations, leading to menopause. In this work, we revisit their male-mate-choice hypothesis by formulating an analogous mathematical model using a system of ordinary differential equations (ODEs). We first show that our ODE model recreates the qualitative behaviour and hence conclusions of key scenarios in Morton et al. (2013). However, since our ODE system is less computationally demanding than their ABM, we also conduct a broader sensitivity analysis over a range of parameters and differing initial conditions to analyse the dependence on their conclusions to underlying assumptions. Our results challenge those of Morton et al. as we find that even the slightest deviation from an exclusive mating preference for younger females would counteract the evolution of menopause. Consequently, we propose that their male-mate-choice hypothesis is incomplete and needs further explanation of how a male strategy to exclusively mate with young females could have arisen in our common ancestors and remained evolutionarily stable for long enough to drive the evolution of old-age female infertility.

Mate guarding in primates arises due to partner scarcity, even if the father provides no paternal care at all.

Paternal care is unusual among primates; in most species males compete with one another for the acquisition of mates and leave the raising of offspring to the mothers. Callitrichids defy this trend with both fathers and older siblings contributing to the care of offspring. We extend a two-strategy population model (paternal care versus male-male competition) to account for various mechanisms that could possibly explain why male callitrichids invest in paternal care over male-male competition, and compare results from callitrichid, chimpanzee and hunter-gatherer life history parameters. The survival benefit to offspring due to care is an insufficient explanation of callitrichid paternal care, and the additional inclusion of differences in lactation-related biology similarly do not change that picture. Instead, paternal care may arise in parallel with, or even as a result of, mate guarding, which in turn is only beneficial when partners are scarce as modelled by the birth sex ratio in callitrichids and menopause in hunter-gatherers. In that situation, care need not even provide any benefit to the young (in the form of a survival bonus) for guarding to out-compete multiple mating competition.

Effects of operational sex ratio, mating age, and male mating history on mating and reproductive behavior in Grapholita molesta.

The short-lived polygamous moth Grapholita molesta (Busck) is an important fruit pest worldwide. Trapping males by synthetic female sex pheromones is not an effective reproductive control strategy. It is important to improve this technology by understanding the mating system of G. molesta. This study investigated mating opportunities and fertile egg production by altering the operational sex ratio, mating age, and male mating history in repeated single mating and multiple mating in the two sexes. Our results showed that the mating and reproductive parameters of virgin males were affected by the number and age of virgin females. Males preferred a female number ≤three-fifths of the male number or ≤2-day-old females, while they discriminated against a female number ≥three times of the male number or ≥5-day-old females. On the other hand, the mating and reproductive parameters of virgin females were affected by repeated single mating and especially multiple mating under different male mating histories. Females preferred once-mated males and discriminated against virgin males. These results indicated that mating systems including more and older virgin females for virgin males and different virgin males for virgin females may be suitable for suppressing G. molesta populations. Hence, these results revealed that preventing mating of virgin adults by synthetic female sex pheromones should be most effective in controlling G. molesta.

Reproductive interference and sensitivity to female pheromones in males and females of two herbivorous mite species.

Competitive interaction between sister species can be affected by reproductive interference (RI) depending on the ability of males to discriminate conspecific from heterospecific mates. We study such interactions in Tetranychus evansi and T. urticae. These spider mites co-occur on solanaceous plants in Southern Europe, and cause important yield losses in tomato crops. Previous studies using Spanish populations found that T. evansi outcompetes T. urticae, and that this is due to unidirectional RI of T. evansi males with T. urticae females. The unidirectional RI is attributed to differences in male mate preference for conspecific females between the two species. Also, differences in the propensity of interspecific web sharing in females plays a role. To investigate proximate mechanisms of this RI, here we study the role of female pheromones on male mate preference and female web sharing. We extracted pheromones from females of the two species, and investigated if males and females were arrested by the pheromone extractions in various concentrations. We observed that T. urticae males were more sensitive to the pheromone extractions and able to discriminate conspecific from heterospecific ones. Tetranychus evansi males, on the other hand, were less sensitive. Females from both species were arrested by conspecific pheromone extraction in lower concentrations. In conclusion, heterospecific mating by T. evansi males, which results in RI, can be explained by their lack of discrimination between female pheromones of the two species. Differences in the propensity of interspecific web sharing in females might not be explained by the pheromones that we investigated.

Macroevolutionary Origin and Adaptive Function of a Polymorphic Female Signal Involved in Sexual Conflict.

Intersexual signals that reveal developmental or mating status in females have evolved repeatedly in many animal lineages. Such signals have functions in sexual conflict over mating and can therefore influence sexually antagonistic coevolution. However, we know little about how female signal development modifies male mating harassment and thereby sexual conflict. Here, we combine phylogenetic comparative analyses of a color polymorphic damselfly genus (Ischnura) with behavioral experiments in one target species to investigate the evolutionary origin and current adaptive function of a developmental female color signal. Many Ischnura species have multiple female color morphs, which include a male-colored morph (male mimics) and one or two female morphs that differ markedly from males (heterochrome females). In Ischnura elegans, males and male-mimicking females express a blue abdominal patch throughout postemergence life. Using phenotypic manipulations, we show that the developmental expression of this signaling trait in heterochrome females reduces premating harassment prior to sexual maturity. Across species this signal evolved repeatedly, but in heterochrome females its origin is contingent on the signal expressed by co-occurring male-mimicking females. Our results suggest that the co-option of a male-like trait to a novel female antiharassment function plays a key role in sexual conflict driven by premating interactions.

Veiled preferences and cryptic female choice could underlie the origin of novel sexual traits.

Males in many species have elaborated sexual traits that females strongly prefer, and these traits often conspicuously differ among species. How novel preferences and traits originate, however, is a challenging evolutionary problem because the initial appearance of only the female preference or only the male trait should reduce the ability to find a suitable mate, which could reduce fitness for individuals possessing those novel alleles. Here, we present a hypothesis for how novel preferences, as well as the novel male traits that females prefer, can originate, be favoured and spread in polyandrous species. Novel preference mutations can arise as 'veiled preferences' that are not expressed when the corresponding male trait is not present in the population, allowing preferences to be hidden from selection, and thus persist. In those cases when a male trait is present, veiled preferences provide a selective advantage, and females disproportionately produce offspring from preferred males through either mate choice or cryptic female choice. This tips the fitness advantage for novel males, allowing both preference and trait to spread, and limiting selection against them in the absence of the corresponding trait or preference.

Proximate mechanisms of the differences in reproductive success of males bearing different alleles of Pgdh - a gene involved in a sexual conflict in bulb mite.

Enzyme polymorphism in phosphogluconate dehydrogenase (Pgdh) is a striking example of single gene polymorphism involved in sexual conflict in bulb mite Rhizoglyphus robini. Males homozygous for the S Pgdh allele were shown to achieve higher reproductive success than FF homozygous males, while negatively influencing fecundity of their female partners. Here, we investigate proximate mechanisms responsible for the increased reproductive success of SS males and find that the S allele is associated with shorter time until copulation, higher copulation frequency and increased sperm production. We also show that Pgdh alleles are probably codominant, with SS males gaining the highest reproductive success, FF males - the lowest - and FS-heterozygous males taking an intermediate position in all fitness parameters differentiating males of different genotypes. Additionally, we confirm the negative effect that S-bearing males impose on the fecundity of females they mate with, showing a clear pattern of interlocus sexual conflict. We discuss that this effect is probably associated with increased copulation frequency. Whereas, contrary to what we have predicted, the S allele does not cause increased general male mobility, we speculate that the S allele-bearing males are more efficient in forcing copulation and/or detecting females.

Parental care compromises feeding in the pumpkinseed (Lepomis gibbosus).

Providing parental care is potentially costly. Costs can arise through elevated energy expenditure or from an increased risk of mortality. A cost of parental care can also occur because a parent is compromised in their ability to forage. We used pumpkinseed Lepomis gibbosus, a fish with an alternative male mating strategy, to test whether parental males differed in their feeding in comparison with females and cuckolder males. To address this question, we examined the stomach contents of female, cuckolder male, and parental male pumpkinseed during the breeding season over an entire diel cycle. We showed that parental males had a lower total weight of food in their stomachs in comparison with females, while cuckolder males did not. Parental males also had a lower weight and number of chironomids in their stomachs. The temporal pattern of feeding of parental males diverged from that of females, and they had a lower probability of pupal chironomids in their stomachs, which implies spatial segregation in foraging. Parental males had a greater probability of conspecific eggs in their stomachs than females, while the probability of egg cannibalism did not differ between cuckolder males and females. Overall, these finding meet predictions in accordance with an assumption that parental care and territoriality can compromise feeding.

Alternative male mating tactics of the endemic Red Sea parrotfish Scarus ferrugineus.

The present study shows that small non-territorial terminal-phase males of the rusty parrotfish Scarus ferrugineus are reproductively active and are comparable with initial-phase males in behaviour, rates of participation during group-spawning and success in streaking into pair spawning. Large territorial terminal-phase males defend contiguous territories for several hours during the morning where they pair spawn with initial-phase females.

KChIP-like auxiliary subunits of Kv4 channels regulate excitability of muscle cells and control male turning behavior during mating in Caenorhabditis elegans.

Voltage-gated Kv4 channels control the excitability of neurons and cardiac myocytes by conducting rapidly activating-inactivating currents. The function of Kv4 channels is profoundly modulated by K(+) channel interacting protein (KChIP) soluble auxiliary subunits. However, the in vivo mechanism of the modulation is not fully understood. Here, we identified three C. elegans KChIP-like (ceKChIP) proteins, NCS-4, NCS-5, and NCS-7. All three ceKChIPs alter electrical characteristics of SHL-1, a C. elegans Kv4 channel ortholog, currents by slowing down inactivation kinetics and shifting voltage dependence of activation to more hyperpolarizing potentials. Native SHL-1 current is completely abolished in cultured myocytes of Triple KO worms in which all three ceKChIP genes are deleted. Reexpression of NCS-4 partially restored expression of functional SHL-1 channels, whereas NCS-4(efm), a NCS-4 mutant with impaired Ca(2+)-binding ability, only enhanced expression of SHL-1 proteins, but failed to transport them from the Golgi apparatus to the cell membrane in body wall muscles of Triple KO worms. Moreover, translational reporter revealed that NCS-4 assembles with SHL-1 K(+) channels in male diagonal muscles. Deletion of either ncs-4 or shl-1 significantly impairs male turning, a behavior controlled by diagonal muscles during mating. The phenotype of the ncs-4 null mutant could be rescued by reexpression of NCS-4, but not NCS-4(efm), further emphasizing the importance of Ca(2+) binding to ceKChIPs in regulating native SHL-1 channel function. Together, these data reveal an evolutionarily conserved mechanism underlying the regulation of Kv4 channels by KChIPs and unravel critical roles of ceKChIPs in regulating muscle cell excitability and animal behavior in C. elegans.

Copulation with immature females increases male fitness in cannibalistic widow spiders.

Copulatory cannibalism of male 'widow' spiders (genus Latrodectus) is a model example of the extreme effects of sexual selection, particularly in L. hasselti and L. geometricus where males typically facilitate cannibalism by females and mate only once. We show that these males can increase their reproductive success by copulating with final-instar, immature females after piercing the female's exoskeleton to access her newly developed sperm storage organs. Females retain sperm through their final moult and have similar fecundity to adult-mated females. This is an adaptive male tactic because immature mating increases insemination success relative to adult mating (which predicts higher paternity) and moreover, rarely ends in cannibalism, so males can mate again. Although successful only during a brief period before the female's final moult, males may employ this tactic when they associate with final-instar females in nature. Consistent with this, one-third of L. hasselti females collected as immatures in nature were already mated. Immature mating alters sexual selection on these otherwise monogynous males, and may explain male traits allowing facultative polygyny in Latrodectus Since male cohabitation with immature females is common among invertebrates, immature mating may be a widespread, previously unrecognized mating tactic, particularly when unmated females are of high reproductive value.

Chemical and Physical Cues Synergistically Affect Mating Behavior Sequences of Male Dasylepida ishigakiensis (Coleoptera: Scarabaeidae).

We investigated physical and chemical cues involved in male mating behavior of the white grub beetle, Dasylepida ishigakiensis (Scarabaeidae). When presented with female attractant pheromone (R)-2-butanol lures in a flight tunnel, nearly all males exhibited orientation and touching behaviors to freshly killed males and females and to intact glass models. Males landed and bent their abdomens on male and female bodies, but not on intact glass models. When treated with one female equivalent (FE) extract, washed immature male bodies and glass models both evoked stronger male responses than untreated equivalents, with the former eliciting a greater response than the treated glass models. Male responses to target male and female bodies decreased with increased numbers of washings of target bodies with organic solvents. These results suggest that the chemical factors that elicit male abdominal bending behavior are present on the body surface in both sexes. Washed immature male bodies treated with 1 FE or one male equivalent (ME) of extract induced strong male abdominal bending behavior. Washed mature female bodies treated with 1 ME extract also evoked male responses. Extracts of both sexes included factors eliciting male abdominal bending behavior. These results suggest that both physical and chemical cues derived from conspecifics cooperate to facilitate male mating recognition in D. ishigakiensis. The mating process of this species in the field is highly synchronized. Thus, after orienting to a female-like object, the only information males require by touching is whether the sex attractant pheromone that attracted them is indeed from a conspecific.

Patterns of sperm swimming behaviour depend on male mating tactic and spawning environment in chinook salmon.

Many species exhibit alternative mating tactics (ARTs), with larger socially dominant males competing for females and smaller males adopting "sneaker" strategies to exploit fertilisation opportunities without competition or courtship. Females typically prefer larger socially dominant males, but their ability to manipulate mating or fertilisation outcomes is largely unknown. Here, using chinook salmon Oncorhynchus tshawytscha, we examined whether the female's ovarian fluid (OF) differentially influences the temporal patterns of sperm swimming traits in ejaculates from non-preferred sneaker ('parr') and preferred (dominant) males. Results demonstrate that OF improves sperm swimming speed and linearity compared to river water, regardless of male mating tactic. We report a novel tactic-specific difference in sperm linearity in which parr male sperm initially maintain straighter trajectories in river water, compared to dominant males, but then rapidly change to less linear and more circular paths over time. Intriguingly, we show that OF counteracts this change in sperm linearity in parr males so that patterns become indistinguishable from dominants when parr sperm swim in OF. Together, these results show that male chinook salmon exhibit differential sperm trait investment strategies depending on reproductive tactic.

Old-male paternity advantage is a function of accumulating sperm and last-male precedence in a butterfly.

Old-male mating advantage has been convincingly demonstrated in Bicyclus anynana butterflies. This intriguing pattern may be explained by two alternative hypotheses: (i) an increased aggressiveness and persistence of older males during courtship, being caused by the older males' low residual reproductive value; and (ii) an active preference of females towards older males what reflects a good genes hypothesis. Against this background, we here investigate postcopulatory sexual selection by double-mating Bicyclus anynana females to older and younger males, thus allowing for sperm competition and cryptic mate choice, and by genotyping the resulting offspring. Virgin females were mated with a younger virgin (2-3 days old) and afterwards an older virgin male (12-13 days old) or vice versa. Older males had a higher paternity success than younger ones, but only when being the second (=last) mating partner, while paternity success was equal among older and younger males when older males were the first mating partner. Older males produced larger spermatophores with much higher numbers of fertile sperm than younger males. Thus, we found no evidence for cryptic female mate choice. Rather, the findings reported here seem to result from a combination of last-male precedence and the number of sperm transferred upon mating, both increasing paternity success.

No detectable changes in reproductive behaviour of Caenorhabditis elegans males after 97 generations under obligatory outcrossing.

In Caenorhabditis elegans, a species reproducing mostly via self-fertilization, numerous signatures of selfing syndrome are observed, including differences in reproductive behaviour compared to related obligatory outcrossing species. In this study we investigated the effect of nearly 100 generations of obligatory outcrossing on several characteristics of male reproductive behaviour. A genetically uniform ancestral population carrying a mutation changing the reproductive system to obligatory outcrossing was split into four independent populations. We predicted that the transition from the natural reproductive system, where males were extremely rare, to obligatory outcrossing, where males comprise 50% of the population and are necessary for reproduction, will increase the selection pressure on higher effectiveness of mating behaviour. Several characteristics of male mating behaviour during a 15 min interaction as well as copulation success were compared between the ancestral and evolved populations. No significant differences in male mating behaviour or fertilization success were detected between generations 1 and 97 of obligatory outcrossing populations. We found, however, that longer contact with females increased chances of successful copulation, although this effect did not differ between populations. We conclude that either selection acting on male mating behaviour has not been strong enough, or mutational input of new adaptive variants has not been sufficient to cause noticeable behavioural differences after 97 generations of evolution starting from genetically uniform population.

Sterility of Aedes albopictus by X-ray Irradiation as an Alternative to γ-ray Irradiation for the Sterile Insect Technique.

The mosquito Aedes albopictus can transmit various arboviral diseases, posing a severe threat to human health. As an environmentally friendly method, sterile insect technology (SIT) is considered an alternative to traditional methods such as chemical pesticides to control Ae. albopictus. In SIT, the sterility of male mosquitoes can be achieved by γ-ray or X-ray radiation. Compared with γ-rays, X-rays are easier to obtain, cheaper, and less harmful. However, there is a lack of comparative assessment of these two types of radiation for SIT under the same controlled conditions. Here, we compared the effects of X-ray and γ-ray radiation on the sterility of Ae. albopictus males under laboratory-controlled conditions. Neither type of radiation affected the number of eggs but significantly reduced the survival time and hatch rate. The same dose of γ-rays caused a higher sterility effect on males than X-rays but had a more significant impact on survival. However, X-rays could achieve the same sterility effect as γ-rays by increasing the radiation dose. For example, X-rays of 60 Gy induced 99% sterility, similar to γ-rays of 40 Gy. In the test of male mating competitiveness, the induced sterility and the male mating competitiveness index were also identical at the same release ratio (sterile males/fertile males). At a release ratio of 7:1, nearly 80% of eggs failed to hatch. Sterile males produced by X-ray and γ-ray radiation had similar male competitiveness in competition with field males. In conclusion, a higher dose of X-rays is required to achieve the same sterility effect, compared to γ-rays. When γ-rays are not readily available, high-dose X-rays can be used instead. This study provides data supporting the selection of more suitable radiation for the field release of sterile male mosquitoes.

The sex pheromone heptacosane enhances the mating competitiveness of sterile Aedes aegypti males.

BACKGROUND: Aedes aegypti is a vector that transmits various viral diseases, including dengue and Zika. The radiation-based sterile insect technique (SIT) has a limited effect on mosquito control because of the difficulty in irradiating males without reducing their mating competitiveness. In this study, the insect sex pheromone heptacosane was applied to Ae. aegypti males to investigate whether it could enhance the mating competitiveness of irradiated males. METHODS: Heptacosane was smeared on the abdomens of Ae. aegypti males that were allowed to mate with untreated virgin females. The insemination rate was used to assess the attractiveness of heptacosane-treated males to females. The pupae were irradiated with different doses of X-rays and γ-rays, and the emergence, survival time, egg number, and hatch rate were detected to find the optimal dose of X-ray and γ-ray radiation. The males irradiated at the optimal dose were smeared with heptacosane, released in different ratios with untreated males, and mated with females. The effect of heptacosane on the mating competitiveness of irradiated mosquitoes was then evaluated by the hatch rate, induced sterility, and mating competitiveness index. RESULTS: Applying heptacosane to Ae. aegypti males significantly increased the insemination rate of females by 20%. Pupal radiation did not affect egg number but significantly reduced survival time and hatch rate. The emergence of the pupae was not affected by X-ray radiation but was affected by γ-ray radiation. Pupae exposed to 60 Gy X-rays and 40 Gy γ-rays were selected for subsequent experiments. After 60 Gy X-ray irradiation or 40 Gy γ-ray irradiation, the average hatch rate was less than 0.1%, and the average survival time was more than 15 days. Moreover, at the same release ratio, the hatch rate of the irradiated group perfumed with heptacosane was lower than that of the group without heptacosane. Conversely, the male sterility and male mating competitiveness index were significantly increased due to the use of heptacosane. CONCLUSIONS: The sex pheromone heptacosane enhanced the interaction between Ae. aegypti males and females. Perfuming males irradiated by X-rays or γ-rays with heptacosane led to a significant increase in mating competitiveness. This study provided a new idea for improving the application effect of SIT.

The hsp70 new functions as a regulator of reproduction both female and male in Ophraella communa.

Heat shock proteins (Hsps) function as molecular chaperones that enable organisms to withstand stress and maintain normal life activities. In this study, we identified heat shock protein 70 (encoded by hsp70), which exhibits a higher expression in the mature male testis than in the unmature testis of Ophraella communa. Tissue expression profile revealed that Ochsp70 levels in males were highest in the testis, whereas those in females were highest in the head. Moreover, the expression of Ochsp70 was found to be significantly induced in female bursa copulatrix after mating. Double-stranded RNA dsOchsp70 was injected into males to performance RNA interference, which significantly decreased the male Ochsp70 expression levels within 20 d post-injection, whereas no effect was observed on the Ochsp70 expression level in the females after mating with dsOchsp70-injected males. However, significant downregulation of female fertility was marked simultaneously. Furthermore, knockdown of female Ochsp70 expression also led to a significant reduction in fertility. Finally, comparative transcriptomic analysis identified glucose dehydrogenase and insulin-like growth factor binding protein as putative downstream targets of Ochsp70. Overall, we deduced that Ochsp70 is an indispensable gene and a potential male mating factor in O. communa, which regulates reproduction.