Male aggressiveness does not explain the frequency of reversed sexual cannibalism

Male aggressiveness does not explain the frequency of reversed sexual cannibalism | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Male aggressiveness does not explain the frequency of reversed sexual cannibalism Narmin Beydizada, Stano Pekár This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5281954/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract In a few species, males often face a choice between mating and/or cannibalizing females. Various factors influence this decision, making it essential to decipher the role of male behavioural variation. In particular, aggressiveness has been proposed to face sexual selection and increase the incidence of cannibalism in such systems. In this study, we investigated the role of male aggressiveness in the likelihood of reversed sexual cannibalism occurring in the female-cannibalistic ground spider Micaria sociabilis . We conducted behavioural experiments to measure male aggressiveness level, and to assess male mating behaviour, along with potential seasonal (spring and summer) and morphological traits (body size, female size). We found that male aggressiveness was a repeatable trait. However, it was not significantly linked to the likelihood of reversed cannibalism or to the likelihood of copulation. Similarly, aggressiveness did not affect the size of a mating plug. Seasonal variation significantly affected reversed cannibalism, with males more likely to engage in cannibalism during summer, while copulation frequency remained consistent between seasons. Additionally, while aggressiveness was not related to male attacks on females, seasonality had a notable impact, with males attacking females more frequently in summer, while females attacked males more in spring. These findings highlight the complexity of mating dynamics in M. sociabilis , pointing to a multifaceted interaction between intrinsic personality traits and extrinsic factors, such as ecological pressures and female condition. Significant statement In some species, males must navigate a trade-off between mating and cannibalizing their female partners. Our study presents surprising results on the complexities behind that choice in Micaria sociabilis spider. While male aggressiveness is often thought to increase the likelihood of cannibalism or mating success, our findings reveal it plays a less decisive role. Instead, seasonal shifts were stronger influences, with males behaving in a choosy way and being more prone to cannibalize in summer, while in spring females were choosier, likely due to high sexual receptivity, a consequence of what was zero reversed cannibalism. These insights challenge traditional views of male aggressiveness and highlight how external factors and mate quality, rather than personality traits, shape mating and cannibalism dynamics. This research offers a fresh perspective on how behavior and ecology intertwine in cannibalistic species. Male aggression copulation seasonal pattern Micaria sociabilis Figures Figure 1 Figure 2 Introduction Because males and females rarely share identical biological imperatives when it comes to reproduction, this often leads to sexual conflict between the sexes (Rowe et al. 1994 ; Chapman et al. 2003 ). Sometimes, such divergent selective pressures on males and females can reach extreme levels, which result in sexual cannibalism (Chapman and Partridge 1996 ; Schneider and Lubin 1998 ; Schneider 2014 ) where one partner—typically the female—kills and consumes the other before, during, or after mating (Polis and Farley 1979 ; Elgar 1992 ). This behaviour has been observed mainly in insects and arachnids (Schneider and Elgar 2005 ), and several hypotheses have been proposed to explain its evolution – for example, mistaken identity (Gould 1984 ), female mate choice (Elgar and Nash 1988 ), or a nutritional benefit for the cannibalizing individual (Newman and Elgar 1991 ). The first one suggests that female aggressiveness, selected for during juvenile phases, spills over into adulthood, resulting in lethal encounters (Arnqvist and Henriksson 1997 ). Although sexual cannibalism has been mainly studied from the female perspective, males can also be selective or aggressive towards potential mates. In a few rare instances, males kill females, a phenomenon known as reversed sexual cannibalism. This behaviour has been observed in a few taxa, including amphipods (Dick 1995 ); isopods (Tsai and Dai 2003 ); crabs (Haddon 1995 ), and spiders (Schütz and Taborsky 2005 ; Sentenská and Pekár 2013 , 2014 ). For example, male Micaria sociabilis Kulczyński spiders may differentiate between old and young females, selectively killing older females while mating with younger ones, likely according to the reproductive potential of the female. This discrimination is driven more by reproductive capacity than by female size or mating status, as reported by Sentenská and Pekár ( 2013 ). Additionally, the highest frequency of reversed cannibalism in this species has been documented when prey availability decreased – only, however, when the sex ratio was female-biased. This suggests that the motivation of M. sociabilis males to attack females can also include some foraging advantages, probably affected by male feeding history during different seasons (Sentenská and Pekár 2013 , 2014 ). These authors also found that bigger males from the summer generation were more likely to cannibalize females, probably because of their physical capability. However, there is room for other proximate factors predicting the incidence of sexual cannibalism and/or its frequency. To date, very few studies have been done to support the impact of behavioural type (personality), and, if so, then only in the case of classic cannibalism. Berning et al. ( 2012 ) brought evidence that more aggressive females of the funnel-web spider Agelenopsis pennsylvanica Koch were more likely to cannibalize mate partners than less aggressive ones. A similar result has also been found in the wolf spider Lycosa hispanica Walckenaer, where less voracious/aggressive females killed only males in poor condition (Rabaneda-Bueno et al. 2014 ). Foellmer and Khadka ( 2013 ) reported that aggressiveness in females of the orb-web spider Argiope aurantia Lucas predicted the likelihood of sexual cannibalism. These examples postulate that sexual cannibalism could be a facet of aggressiveness in an overarching behavioural syndrome (Sih et al. 2004 , 2012 ), and that selection favouring aggressiveness in one context can indirectly increase the incidence of sexual cannibalism (Berning et al. 2012 ). In the context of reversed sexual cannibalism, male aggressiveness in mate choice, i.e. attacking undesired females but mating with preferred ones (Hebets 2003 , 2007 ; Kralj-Fišer et al. 2012 ), could explain the incidence and/or rate of cannibalism. Another factor with a potential to explain the occurrence of cannibalism is the mating status of females. In M. sociabilis , males deposit an amorphous material (plug) on or in the female genitalia once mated, to reduce the access of other males to the female (Sentenská et al. 2015 ). Plugging is a male strategy to avoid sperm competition by monopolizing a female with a single insertion and is widely distributed in spiders (Wigby and Chapman 2004 ; Uhl et al. 2010 ). The property, size, and amount of the plug material in the female genital system differ (Jackson 1980 ; Uhl et al. 2010 ; Kunz et al. 2014 ). In systems such as M. sociabilis , the presence of plug in/on female genitalia may affect or predict male behaviour, i.e., it may trigger males to attack or cannibalize such females or simply to avoid copulating with them (Sentenská and Pekár 2013 , 2014 ; Sentenská et al. 2015 ). Thus, our aim here was to explore whether male aggressiveness could explain the occurrence of copulation or reversed cannibalism in M. sociabilis . We hypothesized that more aggressive males would cannibalize females more often than simply ignoring them, and, most intensively, mated (non-virgin) females. Furthermore, we also expected females with plugs to be more likely to be ignored or attacked/cannibalized by males. Material and Methods Study animal : collection and housing Approximately 103 (in total) individuals (April: 11 adult males, 11 adult females, and 13 juveniles; July: 20 adult males, 12 adult females, 9 subadult females, and 27 juveniles) of M. sociabilis were collected in the field (Lednice park, Brno, Czech Republic) by hand from the tree bark of dozens of oak trees in April and July 2023. Captured spiders were housed individually in glass tubes (diameter 15 mm, length 60 mm) with a layer of gypsum at the bottom, moistened with a few drops of water daily to maintain the required humidity. Spiders were kept at room temperature (approx. 22°C) in 40% relative humidity (RH) and under a natural long-day regime. They were fed regularly with springtails ( Sinella curviesta Brook) to satiation at three-days intervals. Subadult individuals were raised until they reached adulthood, and only then used in experiments. Experimental procedure Each spider was kept in the lab for four to six weeks in total, during which it underwent two behavioural experiments: personality (only males) and mating (males and females). The level of starvation was always standardized for each individual before starting each experiment. All experiments were performed in the laboratory. A small proportion of virgin females ( n = 9) were obtained from the subadult specimens (raised in the lab). Virgin individuals were used in the mating experiment five days after moulting to the adult stage. The body size (prosoma length) of spiders was measured by an ocular micrometer on a stereomicroscope (Olympus SZX 9). Personality assay The personality, namely the aggressiveness (toward prey, Michalko et al. 2017 ; Beydizada and Pekár 2023 ) of males ( n = 31), was recorded according to the number of overkilled (not consumed) prey during a period of 90 min. The personality test was conducted using a small Petri dish (diameter 35 mm, height 11 mm). Spiders were left undisturbed once the experiment started. After the given time elapsed, each spider was carefully removed from its dish, and the total number of killed but not consumed collembolans was recorded under the stereomicroscope. Consumed collembolans were easily recognized from unconsumed ones by having a sucked gaster. The higher the number of overkilled prey, the more aggressive the individual was determined to be (e.g., Maupin and Riechert 2001 ). The trial was repeated after three days, during which time the spiders were starved. Both personality trials were performed under the same conditions (the same start time on both days, approximately at 10 am and the same light regime etc.). In the personality test, the number of collembolans offered was standardized ( n = 10 for each spider). Mating trial In this experiment, the preference of males for mating or cannibalism based on female status (i.e., mating experience) was tested (for each male and female: n = 31). The mating history of spiders from the field collection was unknown (except for those small number of females raised from the sub-adult individuals in the lab), so adult female spiders were assumed to be non-virgin. Mating trials were carried out in transparent containers (diameter 35 mm, height 40 mm) to maximize the encounter rate. The trial was recorded using a Canon Legria HF R606. Spiders were released into the container one after the other (female before male). The female was released into the dish 15 min prior to male release. Recording started once the male was released into the container, and the occurrence of the following behaviours were assessed: 1) classical cannibalism (when the female kills and consumes the male); 2) reversed cannibalism (when the male kills and consumes the female); 3) copulation. When neither copulation nor cannibalism occurred within 20 min from the first contact between male and female, the trial was terminated. Recording was stopped once any event occurred (e.g., cannibalism, copulation). After the mating trial was completed, females were preserved in pure ethanol. The size of the plug (Fig. 1 ) was measured (in µm) as an area using a KEYENCE VHX-5000 digital microscope. It was not possible to score experimental trials blindly due to the way of observations (both manual and video recording). To minimize an observer effect, all observations were conducted by the same person. Data analysis All statistical analyses were conducted in the R environment, version 4.4.0 (R Core Team 2023 ). To assess the repeatability of male aggressiveness, we used a linear mixed-effects model (LME) (Nakagawa and Schielzeth 2010 ) with the number of overkilled prey as the response variable, body size as an explanatory variable, and individual identity as a random variable. Repeatability (R) was estimated using the “rpt”-function from the “rptR”-package. Generalized linear models (GLMs) with a binomial distribution were used to examine the effect of male aggressiveness, male body size, female body size, and season (spring, summer) on the occurrence of reversed cannibalism, copulation, and attack behaviour. A general linear model (LM) was used to study the effect of male size, aggressiveness, and season on the plug size. Results Aggressiveness (the number of overkilled prey) was found to be repeatable in males (LME, R = 0.88, 95% CI [0.773, 0.938], P < 0.0001). The aggressiveness was not affected by season (LME, F 1,28 = 0.14, P = 0.71) nor by male body size (LME, F 1,28 = 0.11, P = 0.75). Neither male aggressiveness (GLM-b, X 2 1 = 0.1, P = 0.8), nor female body size (GLM-b, X 2 1 = 0.4, P = 0.51), nor male body size (GLM-b, X 2 1 = 1.4, P = 0.22) had a significant effect on the likelihood of reversed cannibalism. However, reversed cannibalism was significantly more frequent in summer than in spring (GLM-b, X 2 1 = 11.3, P = 0.0008): it was zero in spring and 50% in summer. In spring, females were more choosy, often ignoring or attacking males. Males copulated with six out of nine (66%) virgin females. Two out of nine (22%) were rejected, and only one (11%) was cannibalized. Males copulated with six out of 22 (27%) non-virgin females. Eight out of 22 (36%) were rejected and eight out of 22 (36%) were cannibalized (see, Supplementary Material S2, ESM1, and ESM2 for copulation and reversed cannibalism respectively). We did not observe classic cannibalism, i.e., female cannibalizing male. The likelihood of copulation was not affected by male aggressiveness (GLM-b, X 2 1 = 0.42, P = 0.51), female size (GLM-b, X 2 1 = 0.06, P = 0.81), male size (GLM-b, X 2 1 = 1.6, P = 0.21), or season (GLM-b, X 2 1 = 2.7, P = 0.10). There was no significant effect of season (LM, F 1,20 = 0.17, P = 0.68), feµale body size (LM, F 1,20 = 0.32, P = 0.58), aggressiveness (LM, F 1,20 = 1.8, P = 0.19), or male body size (LM, F 1,20 = 4.11, P = 0.06) on plug size. Attacks on females by males were not significantly related to male aggressiveness (GLM-b, X 2 1 < 0.1, P = 0.99), female size (GLM-b, X 2 1 = 2.8, P = 0.095), or male size (GLM-b, X 2 1 = 2.2, P = 0.14), but were significantly higher in summer than in spring (GLM-b, X 2 1 = 8.5, P = 0.004, Fig. 2 ). On the other hand, attacks on males by females were significantly higher in spring than in summer (GLM-b, X 2 1 = 13.9, P = 0.0002, Fig. 2 ). Discussion Micaria sociabilis exhibited a repeatable behavioural trait, suggesting it is a stable component of male personality. However, aggressiveness was not associated with either copulation or the likelihood of reversed cannibalism, implying other factors are at play. Interestingly, the frequency of reversed cannibalism varied significantly between spring and summer generations, although no seasonal variation was found for copulation frequency. While male aggressiveness did not correlate with attack behaviour toward females, seasonality had a notable effect, with males being more likely to attack in summer compared to spring. Below, we discuss each of these findings and propose potential explanations for the observed patterns. The repeatability of male aggressiveness, as indicated by the number of overkilled prey, was found to be high, suggesting that this trait is consistent across time and different contexts for individual males. High repeatability in behavioural traits is often indicative of a stable personality component (Réale et al. 2007 ). This finding supports the notion that aggression may be an intrinsic, stable trait in M. sociabilis males, potentially serving as an adaptive strategy in prey acquisition or mating situations. Contrary to our expectations, male aggressiveness had no significant effect on the likelihood of reversed cannibalism. This is surprising because aggressive behaviours often correlate with boldness and risk-taking traits (Sih et al. 2004 ) that could influence the outcome of male-female interactions in cannibalistic species. The lack of association may suggest that reversed cannibalism could be a more opportunistic behaviour, less tied to consistent personality traits, and more affected by immediate physiological conditions (i.e., hunger, nutrient deficiency, or other stress). Alternatively, reversed cannibalism in M. sociabilis might be driven by other factors unrelated to male aggression, such as female condition (body quality, age), as indicated by Sentenská and Pekár ( 2013 ). Alongside female age, we assume that further patterns such as the mating status of both sexes may also shape the occurrence of reversed cannibalism. We also expected that aggressiveness might correlate with male body size, and that the bigger the male, the more cannibalistic it is (Sentenská and Pekár 2013 ). Our study failed to confirm this. We speculate that body size might not have a simple linear relationship with aggression or cannibalism. It is also hard to conclude that there is an optimal size range for males where reversed cannibalism occurs most frequently. Furthermore, some studies have also reported no correlation between body size and aggression (Bakker 1986 ; FitzGerald and Kedney 1987 ). It is also possible that aggression might be driven more by individual personality traits or behavioural syndromes than by physical size. This means that smaller males could be just as aggressive as larger males, leading to no observable size-based pattern in aggression or cannibalism. In another block of experiments, we observed that small males frequently and successfully attacked females almost twice their size, such attacks sometimes resulting in cannibalism (unpublished data). We concur with Sentenská and Pekár ( 2013 ) that deciding whether males were attempting to copulate or kill the female was challenging, as both behaviours share similar patterns, such as active pursuit by the male and brief front-leg attacks. As a result, in our records where neither copulation nor cannibalism occurred within the allotted time (20 minutes), potential data on these behaviours may have been missed, leading to gaps in our understanding of the outcomes. Further examination of male behaviour is essential to better understand the motivations behind copulation attempts versus lethal attacks on females also in natural circumstances. Another intriguing question is when the male’s decision to cannibalize or mate is made. In our experiments, we observed several males abruptly kill a female upon contacting her, while in other cases males performed short attacks following an encounter with a female. This suggests that the decision by males is made before contact with a female. In Philodromus cespitum Wlackenaer, males were able to recognize fine-scale information about the female’s mating status (i.e., virginity and the presence of a plug) from her dragline silk (Sentenská and Pekár 2019 ). We witnessed males following the dragline; thus, their decision to cannibalize could be made on the basis of information from the dragline. It is worth mentioning that males also differed in their motivations to kill females. Some males only killed females but did not consume them, which indicates that nutritional motivation can be excluded. The most often-proposed assumption is that sexual cannibalism happens to prevent starvation (Elgar 1992 ). Indeed, several studies have confirmed that hungry individuals tend to kill their partners at a higher rate than satiated ones (e.g., Andrade 1996 , 1998 ; Schneider and Elgar 2001 ; Wilder and Rypstra 2008 ; Roggenbuck et al. 2011 ). However, the previous study by Sentenská and Pekár ( 2014 ) on M. sociabilis similarly found no significant difference between well-fed and food-deprived males in laboratory experiments, consistent with our results. We failed to find that male aggressiveness affects the copulation frequency either, although previous studies in other species reported that aggressiveness and/or boldness correlate with reproductive success (Sih et al. 2004 ; reviewed by Schuett et al. 2010 ; Munson et al. 2020 ). We suspect the impact of male aggressiveness might be species-specific and/or dependent on the context in which it is displayed. For example, aggressiveness in this species could be more important in male-male competition or resource acquisition than in interactions with females. If aggressiveness primarily serves to deter rival males, it may not play a direct/primary role in influencing copulation success with females. It appears that copulation frequency is more influenced by female status, particularly mating experience (e.g., plug presence), and possibly age. Our data suggest that high copulation occurred with females in the spring period and with virgin females. Surprisingly, the last finding contradicts what was revealed by Sentenská and Pekár ( 2013 ); however, it fits the general pattern of male preference for virgin females, widespread among entelegyne spiders (e.g., Austad 1982 ; Herberstein et al. 2002 ; Gaskett et al. 2004 ; Stoltz et al. 2007 , but see Elgar 1998; Eberhard 2004 ). Moreover, in the cannibalistic wolf spider Allocosa brasiliensis (Petrunkevitch), males also preferentially copulate with virgin females, while mostly killing those which have already mated (Aisenberg et al. 2011 ). Furthermore, we found that the female plug size was not predicted by male aggressiveness, male body size, or season. In our study, we lacked accurate information about the mating statuses of females used in the mating experiments. It is often possible that females with no plug can also be non-virgin, as not all males may apply plugs during mating. However, it is interesting to mention here that the plug was present in all ignored or cannibalized non-virgin females (they were checked only after the mating trial was completed see Mating trial experiment). This indicates the high probability of those females already being plugged before, i.e. having a mated status, according to which we may conclude that plug presence can act as one of the indicators for subsequent male behaviour, which has also been documented in other spider species (Schneider and Lesmono 2009 ). A previous study also reported that M. sociabilis males are not highly successful in removing the plug and/or show little interest in mating with plugged females (Sentenská et al. 2015 ). The seasonal effect on reversed cannibalism was significant, with males being more likely to cannibalize females in July compared to April. It is reasonable to assume that seasonal variation may be linked to a factor such as the natural history, maturation rate, or physiological condition of the species (female receptivity or hormonal levels) or to differences in environmental conditions, such as temperature, humidity, photoperiod changes, or food availability, which could, on the whole, influence mating scenarios or reproductive patterns. For instance, April might indicate the beginning of the breeding season when females are sexually more receptive, and males are more motivated to mate (before the peak of competition later in the season) rather than cannibalize them. Our observation of females behaving in a more selective way toward males in spring compared to summer might support this statement. In contrast, the frequency of copulation was not affected by the season, with no significant difference between April and July. This suggests that copulation may not be strongly influenced by temporal or broader seasonal trends such as the breeding season or environmental conditions. Given the multitude of interacting factors, further research, including controlled experiments (e.g., using energetically stressed males and well-fed males) and detailed ecological observations, would be necessary to clarify whether cannibalism is an adaptive strategy based on immediate need rather than personality, or to unravel the specific mechanisms driving these seasonal variations in M. sociabilis behaviour. Conclusion Our study demonstrates that aggression in M. sociabilis is a consistent and repeatable trait, suggesting that it represents a stable aspect of male personality. However, aggression did not significantly influence copulation frequency or the occurrence of reversed cannibalism, suggesting that these behaviours are driven by other factors, possibly female status or complex environmental conditions. We also observed clear seasonal effects, with reversed cannibalism being more frequent during the summer than in the spring, while copulation rates remained consistent across seasons. Additionally, while male aggressiveness did not predict male attack behavior towards females, seasonality had a notable impact, with males attacking more frequently in summer. These results suggest that aggressiveness may play a more nuanced role, potentially related to male-male competition or resource acquisition, rather than directly influencing mating outcomes. We do not, however, exclude the possibility that other factors such as the nutritional state of the male (a deficit of certain nutritive components in the diet) might better explain the occurrence of copulation and/or reversed cannibalism; indeed, further research is needed to test these possibilities. Such research should explore the potential roles of ecological and physiological factors in shaping these behaviours, including the interaction between male condition (nutritional state, mating status), complex environmental factors, and personality traits. Declarations Competing Interest Authors have no conflict of interest to declare. Author Contribution N. I. Beydizada & S. Pekár: Conceptualization; Designing the experiment; Methodology; Material collection; Data analysis; Review & editing, N. I. Beydizada: Writing–Original draft; Conducting the experiments; Data preparation, S. Pekár: Supervision. Both authors contributed critically to the drafts and gave final approval for publication. Acknowledgment We also thank our colleagues (Masaryk University: Dr. Sepideh Shafai, Dr. Domagoj Gajski, and Ph.D student Warbota Khum, Mendel University) who systematically helped us with the material collection. 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Evol Ecol 19:419–433 Schneider JM, Lesmono K (2009) Courtship raises male fertilization success through post-mating sexual selection in a spider. Proc Royal Soc B: Biol Sci 276:3105–3111 Schneider JM, Elgar MA (2001) Sexual cannibalism and sperm competition in the golden orb-web spider Nephila plumipes (Araneoidea): female and male perspectives. Behav Ecol 12:547–552 Schneider JM (2014) Sexual cannibalism as a manifestation of sexual conflict. Cold Spring Harb Perspect Biol 6(11):a017731 Schuett W, Tregenza T, Dall SR (2010) Sexual selection and animal personality. Biol Rev 85(2):217–246 Schütz D, Taborsky M (2005) Mate choice and sexual conflict in the size dimorphic water spider Argyroneta aquiatica (Araneae, Argyronetidae). J Arachnol 33:767–775 Sih A, Bell A, Johnson JC (2004) Behavioral syndromes: an ecological and evolutionary overview. Trends Ecol Evol 19:372–378 Sih A, Cote J, Evans M, Fogarty S, Pruitt JN (2012) Ecological implications of behavioral syndromes. Ecol Lett 15:278–289 Stoltz JA, McNeil JN, Andrade MCB (2007) Male assess chemical signals to discriminate just-mated females from virgins in redback spiders. Anim Behav 74:1669–1674 Tsai ML, Dai CF (2003) Cannibalism within mating pairs of the parasitic isopod, Ichthyoxenus fushanensis. J Crust Biol 23:662–668 Uhl G, Nessler SH, Schneider JM (2010) Securing paternity in spiders? a review on occurrence and effects of mating plugs and male genital mutilation. Genetica 138:75–104 Wigby S, Chapman T (2004) Sperm competition. Curr Biol 14:R100–R103 Wilder SM, Rypstra AL (2008) Sexual size dimorphism mediates the occurrence of state-dependent sexual cannibalism in a wolf spider. Anim Behav 76:447–454 Supplementary Files ESM1M.sociabliscopulation.mp4 ESM2M.sociabilisreversedcannibalism.mp4 MICARIA.xlsx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5281954","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":369833293,"identity":"2ef69bd3-ec08-426d-bc74-32dbf49676cb","order_by":0,"name":"Narmin Beydizada","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0002-2882-0292","institution":"Masaryk University: Masarykova Univerzita","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Narmin","middleName":"","lastName":"Beydizada","suffix":""},{"id":369833294,"identity":"3b337b0b-6b7b-4538-aba3-82c022c50b66","order_by":1,"name":"Stano Pekár","email":"","orcid":"","institution":"Masaryk University: Masarykova Univerzita","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Stano","middleName":"","lastName":"Pekár","suffix":""}],"badges":[],"createdAt":"2024-10-17 10:24:06","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5281954/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5281954/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":67638392,"identity":"29e1eae1-e176-45fa-b410-39c6227bf920","added_by":"auto","created_at":"2024-10-28 09:49:06","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1010327,"visible":true,"origin":"","legend":"\u003cp\u003ePlug forms in/on the epigyne of a female of \u003cem\u003eM. sociabilis\u003c/em\u003e: (a) no plug (epigyne is uncovered); (b) partial plug (epigyne is not completely covered by a dark substance); (c) a plug before becoming hardened; and (d) a hardened plug covering the whole epigyne. Photos: N. Beydizada.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-5281954/v1/e5f5c2ae413e97a663db7c20.png"},{"id":67638394,"identity":"fff54334-5c70-49b4-b270-a203f259ca32","added_by":"auto","created_at":"2024-10-28 09:49:06","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":6374,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of the attack frequencies between males and females in spring and summer.\u003c/p\u003e","description":"","filename":"Onlinedrawingimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-5281954/v1/c0e5553305ece94ae030e43d.png"},{"id":77048428,"identity":"6ef34185-a442-4795-82e7-b5f1b5e4dfee","added_by":"auto","created_at":"2025-02-24 15:18:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1357487,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5281954/v1/31449627-c4e2-4a41-8296-1b02804f8a9c.pdf"},{"id":67638395,"identity":"3e6220d4-ac30-47c7-99b1-2102bd175048","added_by":"auto","created_at":"2024-10-28 09:49:06","extension":"mp4","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":13330458,"visible":true,"origin":"","legend":"","description":"","filename":"ESM1M.sociabliscopulation.mp4","url":"https://assets-eu.researchsquare.com/files/rs-5281954/v1/eb7d77d01e26c09fb0605128.mp4"},{"id":67638396,"identity":"a3db582f-02e7-42a5-90db-2af2c075bec4","added_by":"auto","created_at":"2024-10-28 09:49:07","extension":"mp4","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":60850291,"visible":true,"origin":"","legend":"","description":"","filename":"ESM2M.sociabilisreversedcannibalism.mp4","url":"https://assets-eu.researchsquare.com/files/rs-5281954/v1/ddc2530b4c670d7f1e12c8d1.mp4"},{"id":67638393,"identity":"4a09baac-c7f8-42b3-81f0-1185f91d0fe3","added_by":"auto","created_at":"2024-10-28 09:49:06","extension":"xlsx","order_by":6,"title":"","display":"","copyAsset":false,"role":"supplement","size":12854,"visible":true,"origin":"","legend":"","description":"","filename":"MICARIA.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-5281954/v1/3a6b45e52002a08b2bfdf8ef.xlsx"}],"financialInterests":"","formattedTitle":"Male aggressiveness does not explain the frequency of reversed sexual cannibalism","fulltext":[{"header":"Introduction","content":"\u003cp\u003eBecause males and females rarely share identical biological imperatives when it comes to reproduction, this often leads to sexual conflict between the sexes (Rowe et al. \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e1994\u003c/span\u003e; Chapman et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2003\u003c/span\u003e). Sometimes, such divergent selective pressures on males and females can reach extreme levels, which result in sexual cannibalism (Chapman and Partridge \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e1996\u003c/span\u003e; Schneider and Lubin \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e1998\u003c/span\u003e; Schneider \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) where one partner\u0026mdash;typically the female\u0026mdash;kills and consumes the other before, during, or after mating (Polis and Farley \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e1979\u003c/span\u003e; Elgar \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1992\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis behaviour has been observed mainly in insects and arachnids (Schneider and Elgar \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2005\u003c/span\u003e), and several hypotheses have been proposed to explain its evolution \u0026ndash; for example, mistaken identity (Gould \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e1984\u003c/span\u003e), female mate choice (Elgar and Nash \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e1988\u003c/span\u003e), or a nutritional benefit for the cannibalizing individual (Newman and Elgar \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e1991\u003c/span\u003e). The first one suggests that female aggressiveness, selected for during juvenile phases, spills over into adulthood, resulting in lethal encounters (Arnqvist and Henriksson \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e1997\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAlthough sexual cannibalism has been mainly studied from the female perspective, males can also be selective or aggressive towards potential mates. In a few rare instances, males kill females, a phenomenon known as reversed sexual cannibalism. This behaviour has been observed in a few taxa, including amphipods (Dick \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e1995\u003c/span\u003e); isopods (Tsai and Dai \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2003\u003c/span\u003e); crabs (Haddon \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e1995\u003c/span\u003e), and spiders (Sch\u0026uuml;tz and Taborsky \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2005\u003c/span\u003e; Sentensk\u0026aacute; and Pek\u0026aacute;r \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). For example, male \u003cem\u003eMicaria sociabilis\u003c/em\u003e Kulczyński spiders may differentiate between old and young females, selectively killing older females while mating with younger ones, likely according to the reproductive potential of the female. This discrimination is driven more by reproductive capacity than by female size or mating status, as reported by Sentensk\u0026aacute; and Pek\u0026aacute;r (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Additionally, the highest frequency of reversed cannibalism in this species has been documented when prey availability decreased \u0026ndash; only, however, when the sex ratio was female-biased. This suggests that the motivation of \u003cem\u003eM. sociabilis\u003c/em\u003e males to attack females can also include some foraging advantages, probably affected by male feeding history during different seasons (Sentensk\u0026aacute; and Pek\u0026aacute;r \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). These authors also found that bigger males from the summer generation were more likely to cannibalize females, probably because of their physical capability.\u003c/p\u003e \u003cp\u003eHowever, there is room for other proximate factors predicting the incidence of sexual cannibalism and/or its frequency. To date, very few studies have been done to support the impact of behavioural type (personality), and, if so, then only in the case of classic cannibalism. Berning et al. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2012\u003c/span\u003e) brought evidence that more aggressive females of the funnel-web spider \u003cem\u003eAgelenopsis pennsylvanica\u003c/em\u003e Koch were more likely to cannibalize mate partners than less aggressive ones. A similar result has also been found in the wolf spider \u003cem\u003eLycosa hispanica\u003c/em\u003e Walckenaer, where less voracious/aggressive females killed only males in poor condition (Rabaneda-Bueno et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Foellmer and Khadka (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2013\u003c/span\u003e) reported that aggressiveness in females of the orb-web spider \u003cem\u003eArgiope aurantia\u003c/em\u003e Lucas predicted the likelihood of sexual cannibalism. These examples postulate that sexual cannibalism could be a facet of aggressiveness in an overarching behavioural syndrome (Sih et al. \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2004\u003c/span\u003e, \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), and that selection favouring aggressiveness in one context can indirectly increase the incidence of sexual cannibalism (Berning et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). In the context of reversed sexual cannibalism, male aggressiveness in mate choice, i.e. attacking undesired females but mating with preferred ones (Hebets \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2003\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Kralj-Fišer et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), could explain the incidence and/or rate of cannibalism.\u003c/p\u003e \u003cp\u003eAnother factor with a potential to explain the occurrence of cannibalism is the mating status of females. In \u003cem\u003eM. sociabilis\u003c/em\u003e, males deposit an amorphous material (plug) on or in the female genitalia once mated, to reduce the access of other males to the female (Sentensk\u0026aacute; et al. \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Plugging is a male strategy to avoid sperm competition by monopolizing a female with a single insertion and is widely distributed in spiders (Wigby and Chapman \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Uhl et al. \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). The property, size, and amount of the plug material in the female genital system differ (Jackson \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e1980\u003c/span\u003e; Uhl et al. \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Kunz et al. \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). In systems such as \u003cem\u003eM. sociabilis\u003c/em\u003e, the presence of plug in/on female genitalia may affect or predict male behaviour, i.e., it may trigger males to attack or cannibalize such females or simply to avoid copulating with them (Sentensk\u0026aacute; and Pek\u0026aacute;r \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Sentensk\u0026aacute; et al. \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2015\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThus, our aim here was to explore whether male aggressiveness could explain the occurrence of copulation or reversed cannibalism in \u003cem\u003eM. sociabilis\u003c/em\u003e. We hypothesized that more aggressive males would cannibalize females more often than simply ignoring them, and, most intensively, mated (non-virgin) females. Furthermore, we also expected females with plugs to be more likely to be ignored or attacked/cannibalized by males.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003e \u003cem\u003eStudy animal\u003c/em\u003e: \u003cem\u003ecollection and housing\u003c/em\u003e\u003c/p\u003e \u003cp\u003eApproximately 103 (in total) individuals (April: 11 adult males, 11 adult females, and 13 juveniles; July: 20 adult males, 12 adult females, 9 subadult females, and 27 juveniles) of \u003cem\u003eM. sociabilis\u003c/em\u003e were collected in the field (Lednice park, Brno, Czech Republic) by hand from the tree bark of dozens of oak trees in April and July 2023. Captured spiders were housed individually in glass tubes (diameter 15 mm, length 60 mm) with a layer of gypsum at the bottom, moistened with a few drops of water daily to maintain the required humidity. Spiders were kept at room temperature (approx. 22\u0026deg;C) in 40% relative humidity (RH) and under a natural long-day regime. They were fed regularly with springtails (\u003cem\u003eSinella curviesta\u003c/em\u003e Brook) to satiation at three-days intervals. Subadult individuals were raised until they reached adulthood, and only then used in experiments.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eExperimental procedure\u003c/h2\u003e \u003cp\u003eEach spider was kept in the lab for four to six weeks in total, during which it underwent two behavioural experiments: personality (only males) and mating (males and females). The level of starvation was always standardized for each individual before starting each experiment. All experiments were performed in the laboratory. A small proportion of virgin females (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;9) were obtained from the subadult specimens (raised in the lab). Virgin individuals were used in the mating experiment five days after moulting to the adult stage. The body size (prosoma length) of spiders was measured by an ocular micrometer on a stereomicroscope (Olympus SZX 9).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePersonality assay\u003c/h3\u003e\n\u003cp\u003eThe personality, namely the aggressiveness (toward prey, Michalko et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Beydizada and Pek\u0026aacute;r \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) of males (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;31), was recorded according to the number of overkilled (not consumed) prey during a period of 90 min. The personality test was conducted using a small Petri dish (diameter 35 mm, height 11 mm). Spiders were left undisturbed once the experiment started. After the given time elapsed, each spider was carefully removed from its dish, and the total number of killed but not consumed collembolans was recorded under the stereomicroscope. Consumed collembolans were easily recognized from unconsumed ones by having a sucked gaster. The higher the number of overkilled prey, the more aggressive the individual was determined to be (e.g., Maupin and Riechert \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2001\u003c/span\u003e). The trial was repeated after three days, during which time the spiders were starved. Both personality trials were performed under the same conditions (the same start time on both days, approximately at 10 am and the same light regime etc.). In the personality test, the number of collembolans offered was standardized (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10 for each spider).\u003c/p\u003e\n\u003ch3\u003eMating trial\u003c/h3\u003e\n\u003cp\u003eIn this experiment, the preference of males for mating or cannibalism based on female status (i.e., mating experience) was tested (for each male and female: \u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;31). The mating history of spiders from the field collection was unknown (except for those small number of females raised from the sub-adult individuals in the lab), so adult female spiders were assumed to be non-virgin.\u003c/p\u003e \u003cp\u003eMating trials were carried out in transparent containers (diameter 35 mm, height 40 mm) to maximize the encounter rate. The trial was recorded using a Canon Legria HF R606. Spiders were released into the container one after the other (female before male). The female was released into the dish 15 min prior to male release. Recording started once the male was released into the container, and the occurrence of the following behaviours were assessed: 1) classical cannibalism (when the female kills and consumes the male); 2) reversed cannibalism (when the male kills and consumes the female); 3) copulation. When neither copulation nor cannibalism occurred within 20 min from the first contact between male and female, the trial was terminated. Recording was stopped once any event occurred (e.g., cannibalism, copulation).\u003c/p\u003e \u003cp\u003eAfter the mating trial was completed, females were preserved in pure ethanol. The size of the plug (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) was measured (in \u0026micro;m) as an area using a KEYENCE VHX-5000 digital microscope.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIt was not possible to score experimental trials blindly due to the way of observations (both manual and video recording). To minimize an observer effect, all observations were conducted by the same person.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eData analysis\u003c/h2\u003e \u003cp\u003eAll statistical analyses were conducted in the R environment, version 4.4.0 (R Core Team \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). To assess the repeatability of male aggressiveness, we used a linear mixed-effects model (LME) (Nakagawa and Schielzeth \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) with the number of overkilled prey as the response variable, body size as an explanatory variable, and individual identity as a random variable. Repeatability (R) was estimated using the \u0026ldquo;rpt\u0026rdquo;-function from the \u0026ldquo;rptR\u0026rdquo;-package. Generalized linear models (GLMs) with a binomial distribution were used to examine the effect of male aggressiveness, male body size, female body size, and season (spring, summer) on the occurrence of reversed cannibalism, copulation, and attack behaviour. A general linear model (LM) was used to study the effect of male size, aggressiveness, and season on the plug size.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eAggressiveness (the number of overkilled prey) was found to be repeatable in males (LME, R\u0026thinsp;=\u0026thinsp;0.88, 95% CI [0.773, 0.938], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). The aggressiveness was not affected by season (LME, \u003cem\u003eF\u003c/em\u003e\u003csub\u003e1,28\u003c/sub\u003e = 0.14, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.71) nor by male body size (LME, \u003cem\u003eF\u003c/em\u003e\u003csub\u003e1,28\u003c/sub\u003e = 0.11, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.75).\u003c/p\u003e \u003cp\u003eNeither male aggressiveness (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;0.1, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.8), nor female body size (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;0.4, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.51), nor male body size (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;1.4, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.22) had a significant effect on the likelihood of reversed cannibalism. However, reversed cannibalism was significantly more frequent in summer than in spring (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;11.3, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0008): it was zero in spring and 50% in summer.\u003c/p\u003e \u003cp\u003eIn spring, females were more choosy, often ignoring or attacking males. Males copulated with six out of nine (66%) virgin females. Two out of nine (22%) were rejected, and only one (11%) was cannibalized. Males copulated with six out of 22 (27%) non-virgin females. Eight out of 22 (36%) were rejected and eight out of 22 (36%) were cannibalized (see, Supplementary Material S2, ESM1, and ESM2 for copulation and reversed cannibalism respectively). We did not observe classic cannibalism, i.e., female cannibalizing male. The likelihood of copulation was not affected by male aggressiveness (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;0.42, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.51), female size (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;0.06, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.81), male size (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;1.6, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.21), or season (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;2.7, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.10).\u003c/p\u003e \u003cp\u003eThere was no significant effect of season (LM, \u003cem\u003eF\u003c/em\u003e\u003csub\u003e1,20\u003c/sub\u003e = 0.17, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.68), fe\u0026micro;ale body size (LM, \u003cem\u003eF\u003c/em\u003e\u003csub\u003e1,20\u003c/sub\u003e = 0.32, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.58), aggressiveness (LM, \u003cem\u003eF\u003c/em\u003e\u003csub\u003e1,20\u003c/sub\u003e = 1.8, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.19), or male body size (LM, \u003cem\u003eF\u003c/em\u003e\u003csub\u003e1,20\u003c/sub\u003e = 4.11, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.06) on plug size.\u003c/p\u003e \u003cp\u003eAttacks on females by males were not significantly related to male aggressiveness (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.1, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.99), female size (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;2.8, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.095), or male size (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;2.2, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.14), but were significantly higher in summer than in spring (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;8.5, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.004, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). On the other hand, attacks on males by females were significantly higher in spring than in summer (GLM-b, \u003cem\u003eX\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;13.9, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0002, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003e \u003cem\u003eMicaria sociabilis\u003c/em\u003e exhibited a repeatable behavioural trait, suggesting it is a stable component of male personality. However, aggressiveness was not associated with either copulation or the likelihood of reversed cannibalism, implying other factors are at play. Interestingly, the frequency of reversed cannibalism varied significantly between spring and summer generations, although no seasonal variation was found for copulation frequency. While male aggressiveness did not correlate with attack behaviour toward females, seasonality had a notable effect, with males being more likely to attack in summer compared to spring. Below, we discuss each of these findings and propose potential explanations for the observed patterns.\u003c/p\u003e \u003cp\u003eThe repeatability of male aggressiveness, as indicated by the number of overkilled prey, was found to be high, suggesting that this trait is consistent across time and different contexts for individual males. High repeatability in behavioural traits is often indicative of a stable personality component (R\u0026eacute;ale et al. \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). This finding supports the notion that aggression may be an intrinsic, stable trait in \u003cem\u003eM. sociabilis\u003c/em\u003e males, potentially serving as an adaptive strategy in prey acquisition or mating situations.\u003c/p\u003e \u003cp\u003eContrary to our expectations, male aggressiveness had no significant effect on the likelihood of reversed cannibalism. This is surprising because aggressive behaviours often correlate with boldness and risk-taking traits (Sih et al. \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2004\u003c/span\u003e) that could influence the outcome of male-female interactions in cannibalistic species. The lack of association may suggest that reversed cannibalism could be a more opportunistic behaviour, less tied to consistent personality traits, and more affected by immediate physiological conditions (i.e., hunger, nutrient deficiency, or other stress). Alternatively, reversed cannibalism in \u003cem\u003eM. sociabilis\u003c/em\u003e might be driven by other factors unrelated to male aggression, such as female condition (body quality, age), as indicated by Sentensk\u0026aacute; and Pek\u0026aacute;r (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Alongside female age, we assume that further patterns such as the mating status of both sexes may also shape the occurrence of reversed cannibalism.\u003c/p\u003e \u003cp\u003eWe also expected that aggressiveness might correlate with male body size, and that the bigger the male, the more cannibalistic it is (Sentensk\u0026aacute; and Pek\u0026aacute;r \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Our study failed to confirm this. We speculate that body size might not have a simple linear relationship with aggression or cannibalism. It is also hard to conclude that there is an optimal size range for males where reversed cannibalism occurs most frequently. Furthermore, some studies have also reported no correlation between body size and aggression (Bakker \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e1986\u003c/span\u003e; FitzGerald and Kedney \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1987\u003c/span\u003e). It is also possible that aggression might be driven more by individual personality traits or behavioural syndromes than by physical size. This means that smaller males could be just as aggressive as larger males, leading to no observable size-based pattern in aggression or cannibalism. In another block of experiments, we observed that small males frequently and successfully attacked females almost twice their size, such attacks sometimes resulting in cannibalism (unpublished data).\u003c/p\u003e \u003cp\u003eWe concur with Sentensk\u0026aacute; and Pek\u0026aacute;r (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e) that deciding whether males were attempting to copulate or kill the female was challenging, as both behaviours share similar patterns, such as active pursuit by the male and brief front-leg attacks. As a result, in our records where neither copulation nor cannibalism occurred within the allotted time (20 minutes), potential data on these behaviours may have been missed, leading to gaps in our understanding of the outcomes. Further examination of male behaviour is essential to better understand the motivations behind copulation attempts \u003cem\u003eversus\u003c/em\u003e lethal attacks on females also in natural circumstances.\u003c/p\u003e \u003cp\u003eAnother intriguing question is when the male\u0026rsquo;s decision to cannibalize or mate is made. In our experiments, we observed several males abruptly kill a female upon contacting her, while in other cases males performed short attacks following an encounter with a female. This suggests that the decision by males is made before contact with a female. In \u003cem\u003ePhilodromus cespitum\u003c/em\u003e Wlackenaer, males were able to recognize fine-scale information about the female\u0026rsquo;s mating status (i.e., virginity and the presence of a plug) from her dragline silk (Sentensk\u0026aacute; and Pek\u0026aacute;r \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). We witnessed males following the dragline; thus, their decision to cannibalize could be made on the basis of information from the dragline.\u003c/p\u003e \u003cp\u003eIt is worth mentioning that males also differed in their motivations to kill females. Some males only killed females but did not consume them, which indicates that nutritional motivation can be excluded. The most often-proposed assumption is that sexual cannibalism happens to prevent starvation (Elgar \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1992\u003c/span\u003e). Indeed, several studies have confirmed that hungry individuals tend to kill their partners at a higher rate than satiated ones (e.g., Andrade \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e1996\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e1998\u003c/span\u003e; Schneider and Elgar \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2001\u003c/span\u003e; Wilder and Rypstra \u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e2008\u003c/span\u003e; Roggenbuck et al. \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). However, the previous study by Sentensk\u0026aacute; and Pek\u0026aacute;r (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) on \u003cem\u003eM. sociabilis\u003c/em\u003e similarly found no significant difference between well-fed and food-deprived males in laboratory experiments, consistent with our results.\u003c/p\u003e \u003cp\u003eWe failed to find that male aggressiveness affects the copulation frequency either, although previous studies in other species reported that aggressiveness and/or boldness correlate with reproductive success (Sih et al. \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; reviewed by Schuett et al. \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Munson et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). We suspect the impact of male aggressiveness might be species-specific and/or dependent on the context in which it is displayed. For example, aggressiveness in this species could be more important in male-male competition or resource acquisition than in interactions with females. If aggressiveness primarily serves to deter rival males, it may not play a direct/primary role in influencing copulation success with females. It appears that copulation frequency is more influenced by female status, particularly mating experience (e.g., plug presence), and possibly age. Our data suggest that high copulation occurred with females in the spring period and with virgin females. Surprisingly, the last finding contradicts what was revealed by Sentensk\u0026aacute; and Pek\u0026aacute;r (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e); however, it fits the general pattern of male preference for virgin females, widespread among entelegyne spiders (e.g., Austad \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e1982\u003c/span\u003e; Herberstein et al. \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2002\u003c/span\u003e; Gaskett et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Stoltz et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2007\u003c/span\u003e, but see Elgar 1998; Eberhard \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Moreover, in the cannibalistic wolf spider \u003cem\u003eAllocosa brasiliensis\u003c/em\u003e (Petrunkevitch), males also preferentially copulate with virgin females, while mostly killing those which have already mated (Aisenberg et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2011\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eFurthermore, we found that the female plug size was not predicted by male aggressiveness, male body size, or season. In our study, we lacked accurate information about the mating statuses of females used in the mating experiments. It is often possible that females with no plug can also be non-virgin, as not all males may apply plugs during mating. However, it is interesting to mention here that the plug was present in all ignored or cannibalized non-virgin females (they were checked only after the mating trial was completed see \u003cem\u003eMating trial\u003c/em\u003e experiment). This indicates the high probability of those females already being plugged before, i.e. having a mated status, according to which we may conclude that plug presence can act as one of the indicators for subsequent male behaviour, which has also been documented in other spider species (Schneider and Lesmono \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). A previous study also reported that \u003cem\u003eM. sociabilis\u003c/em\u003e males are not highly successful in removing the plug and/or show little interest in mating with plugged females (Sentensk\u0026aacute; et al. \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2015\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe seasonal effect on reversed cannibalism was significant, with males being more likely to cannibalize females in July compared to April. It is reasonable to assume that seasonal variation may be linked to a factor such as the natural history, maturation rate, or physiological condition of the species (female receptivity or hormonal levels) or to differences in environmental conditions, such as temperature, humidity, photoperiod changes, or food availability, which could, on the whole, influence mating scenarios or reproductive patterns. For instance, April might indicate the beginning of the breeding season when females are sexually more receptive, and males are more motivated to mate (before the peak of competition later in the season) rather than cannibalize them. Our observation of females behaving in a more selective way toward males in spring compared to summer might support this statement. In contrast, the frequency of copulation was not affected by the season, with no significant difference between April and July. This suggests that copulation may not be strongly influenced by temporal or broader seasonal trends such as the breeding season or environmental conditions. Given the multitude of interacting factors, further research, including controlled experiments (e.g., using energetically stressed males and well-fed males) and detailed ecological observations, would be necessary to clarify whether cannibalism is an adaptive strategy based on immediate need rather than personality, or to unravel the specific mechanisms driving these seasonal variations in \u003cem\u003eM. sociabilis\u003c/em\u003e behaviour.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur study demonstrates that aggression in \u003cem\u003eM. sociabilis\u003c/em\u003e is a consistent and repeatable trait, suggesting that it represents a stable aspect of male personality. However, aggression did not significantly influence copulation frequency or the occurrence of reversed cannibalism, suggesting that these behaviours are driven by other factors, possibly female status or complex environmental conditions. We also observed clear seasonal effects, with reversed cannibalism being more frequent during the summer than in the spring, while copulation rates remained consistent across seasons. Additionally, while male aggressiveness did not predict male attack behavior towards females, seasonality had a notable impact, with males attacking more frequently in summer. These results suggest that aggressiveness may play a more nuanced role, potentially related to male-male competition or resource acquisition, rather than directly influencing mating outcomes. We do not, however, exclude the possibility that other factors such as the nutritional state of the male (a deficit of certain nutritive components in the diet) might better explain the occurrence of copulation and/or reversed cannibalism; indeed, further research is needed to test these possibilities. Such research should explore the potential roles of ecological and physiological factors in shaping these behaviours, including the interaction between male condition (nutritional state, mating status), complex environmental factors, and personality traits.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCompeting Interest\u003c/h2\u003e \u003cp\u003eAuthors have no conflict of interest to declare.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e \u003cp\u003eN. I. Beydizada \u0026amp; S. Pek\u0026aacute;r: Conceptualization; Designing the experiment; Methodology; Material collection; Data analysis; Review \u0026amp; editing, N. I. Beydizada: Writing\u0026ndash;Original draft; Conducting the experiments; Data preparation, S. Pek\u0026aacute;r: Supervision. Both authors contributed critically to the drafts and gave final approval for publication.\u003c/p\u003e\u003ch2\u003eAcknowledgment\u003c/h2\u003e \u003cp\u003eWe also thank our colleagues (Masaryk University: Dr. Sepideh Shafai, Dr. Domagoj Gajski, and Ph.D student Warbota Khum, Mendel University) who systematically helped us with the material collection.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e \u003cp\u003eThe Supplementary Material (S1 and S2) provides all data generated during this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAisenberg A, Costa FG, Gonz\u0026aacute;les M (2011) Male sexual cannibalism in a sand-dwelling wolf spider with sex role reversal. Biol J Linn Soc 103:68\u0026ndash;75\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAndrade MCB (1996) Sexual selection for male sacrifice in the Australian redback spider. Science 271:70\u0026ndash;72\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAndrade MCB (1998) Female hunger can explain variation in cannibalistic behavior despite male sacrifice in redback spiders. Behav Ecol 9:33\u0026ndash;42\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eArnqvist G, Henriksson S (1997) Sexual cannibalism in the fishing spider and a model for the evolution of sexual cannibalism based on genetic constraints. Evol Ecol 11:255\u0026ndash;273\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAustad SN (1982) First male sperm priority in the bowl and doily spider, Frontinella pyramitela (Walckenaer). Evolution 36:777\u0026ndash;785\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBakker TCM (1986) Aggressiveness in sticklebacks (Gasterosteus aculeatus L.): a behaviour-genetic study. 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Anim Behav 76:447\u0026ndash;454\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Male aggression, copulation, seasonal pattern, Micaria sociabilis","lastPublishedDoi":"10.21203/rs.3.rs-5281954/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5281954/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn a few species, males often face a choice between mating and/or cannibalizing females. Various factors influence this decision, making it essential to decipher the role of male behavioural variation. In particular, aggressiveness has been proposed to face sexual selection and increase the incidence of cannibalism in such systems. In this study, we investigated the role of male aggressiveness in the likelihood of reversed sexual cannibalism occurring in the female-cannibalistic ground spider \u003cem\u003eMicaria sociabilis\u003c/em\u003e. We conducted behavioural experiments to measure male aggressiveness level, and to assess male mating behaviour, along with potential seasonal (spring and summer) and morphological traits (body size, female size). We found that male aggressiveness was a repeatable trait. However, it was not significantly linked to the likelihood of reversed cannibalism or to the likelihood of copulation. Similarly, aggressiveness did not affect the size of a mating plug. Seasonal variation significantly affected reversed cannibalism, with males more likely to engage in cannibalism during summer, while copulation frequency remained consistent between seasons. Additionally, while aggressiveness was not related to male attacks on females, seasonality had a notable impact, with males attacking females more frequently in summer, while females attacked males more in spring. These findings highlight the complexity of mating dynamics in \u003cem\u003eM. sociabilis\u003c/em\u003e, pointing to a multifaceted interaction between intrinsic personality traits and extrinsic factors, such as ecological pressures and female condition.\u003c/p\u003e \u003cp\u003eSignificant statement\u003c/p\u003e \u003cp\u003eIn some species, males must navigate a trade-off between mating and cannibalizing their female partners. Our study presents surprising results on the complexities behind that choice in \u003cem\u003eMicaria sociabilis\u003c/em\u003e spider. While male aggressiveness is often thought to increase the likelihood of cannibalism or mating success, our findings reveal it plays a less decisive role. Instead, seasonal shifts were stronger influences, with males behaving in a choosy way and being more prone to cannibalize in summer, while in spring females were choosier, likely due to high sexual receptivity, a consequence of what was zero reversed cannibalism. These insights challenge traditional views of male aggressiveness and highlight how external factors and mate quality, rather than personality traits, shape mating and cannibalism dynamics. This research offers a fresh perspective on how behavior and ecology intertwine in cannibalistic species.\u003c/p\u003e","manuscriptTitle":"Male aggressiveness does not explain the frequency of reversed sexual cannibalism","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-10-28 09:49:01","doi":"10.21203/rs.3.rs-5281954/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9355f22c-9371-45c7-be01-bd036f3767de","owner":[],"postedDate":"October 28th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-02-24T15:09:55+00:00","versionOfRecord":[],"versionCreatedAt":"2024-10-28 09:49:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5281954","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5281954","identity":"rs-5281954","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}