Supplementary Information

The online version contains supplementary material available at 10.1038/s41598-025-91403-3.

Keywords: Kleptoparasitism, Pirate parasitism,Cotesia kariyai,Meteorus pulchricornis, Multiparasitism,Mythimna loreyi

Subject terms: Behavioural ecology, Animal behaviour, Entomology

Experiment 1: host acceptance and oviposition

Regardless of the host instar or previous oviposition by the heterogeneous parasitoid, allCk females exhibited oviposition behavior towardsMyl caterpillars, similar to their behavior toward their usual host,Mys (Supplementary FigureS1a). The number ofCk eggs in ovipositedMyl caterpillars, ranged from 53.7 ± 17.8 to 59.0 ± 18.3 (mean ± SD,n = 20 for each), and did not vary significantly among host instars or in relation to previous parasitism. The number ofCk eggs deposited did not differ significantly from those in the usual host,Mys (Supplementary FigureS1b, ANOVA,F_{6, 133} = 0.19,p > 0.05). Similarly, over 85.0% (n = 30 for each) ofMp females acceptedMyl caterpillars for oviposition, regardless of the host instar or previous oviposition by the heterogeneous parasitoid, and the difference in the host acceptance rate did not differ significantly amongMyl instars or in relation previous parasitism (χ² = 3.41, df = 5,p > 0.05, Supplementary FigureS1c). A singleMp egg was consistently oviposited inMyl caterpillars without exception (Supplementary FigureS1d).

Experiment 2: single-parasitism experiments

Regardless of the host instar,Ck never emerged fromCk-ovipositedMyl caterpillars (Supplementary Figure S2a,n = 200 for each). AmongCk-ovipositedMyl caterpillars, 83.0–86.5% of larvae survived until pupation, whereas the remainder died without emergence ofCk (Supplementary Figure S2a). In contrast,Mp successfully emerged from 76.7 to 86.7% ofMp-ovipositedMyl caterpillars (Supplementary Figure S2b,n = 30 for each). The difference in theMp emergence rate did not differ significantly amongMyl instars (χ² = 1.25, df = 2,p > 0.05, Supplementary Figure S2b).

Experiment 3: multiparasitism experiments in different host instars

Among multiparasitized caterpillars, parasitoid wasps emerged from 50.0 to 90.0% of the caterpillars (Fig. 1a). Regardless of host instar or order of oviposition, no instances were observed in which both parasitoid wasps emerged from a single larva. Interestingly,Ck emerged from 5.0 to 15.0% ofMyl caterpillars (Fig. 1a). The successful parasitism rate ofCk did not differ among treatments (χ² = 4.56, df = 5,p > 0.05). The number of emergedCk adult perMyl caterpillar, ranging from 25.7 ± 13.8 to 45.6 ± 21.4 (mean ± SD) on average, was not significantly different among caterpillar instars or order of oviposition. However, significantly fewerCk adults emerged fromMyl caterpillars than from their usual host,Mys (Fig. 1b, ANOVA,F_{6, 47} = 7.028,p < 0.05, Tukey-Kramer,p < 0.05).

Regardless of the host instar or order of oviposition, the successful parasitism rate ofMp (31.7–73.3%) was significantly higher than that ofCk (Fig. 1a, binomial test,p < 0.05). ForCk emerging fromMyl, all 30Ck females (5 per treatment) showed oviposition behavior towardMys caterpillars, and their offspring emerged from the caterpillars. The number ofCk adults that emerged from those caterpillars did not differ significantly among treatments (Supplementary Figure S3, ANOVA,F_{5, 24} = 0.256,p < 0.933).

Experiment 4: multiparasitism in different sequences and intervals

Successful parasitism byCk occurred whenCk oviposited from 24 h before until 12 h afterMp (Fig. 2a). Beyond these times, no successful parasitism byCk was observed. Under experimental conditions in which successful parasitism byCk was observed, the success rate ofCk ranged from 5.0 to 20.0%. The latter occurred whenCk oviposited 12 h beforeMp, but the success rate was significantly lower whenCk oviposited 24 h beforeMp (Fig. 2a, χ² = 38.04, df = 7,p < 0.05; Tukey’s WSD,p < 0.05). The number of emergedCk adults perMyl caterpillar, ranging from 26.0 ± 17.1 to 38.4 ± 11.7 (mean ± SD) on average, was not significantly different among conditions, but they were significantly fewer than the number ofCk adults that emerged from their usual host,Mys (78.1 ± 16.7) (Fig. 2b, ANOVA,F_{5, 36} = 16.05,p < 0.05, Tukey-Kramer,p < 0.05). In all conditions, the successful parasitism rate ofMp was significantly higher than that ofCk (Fig. 2a, binomial test,p < 0.001).

Experiment 5: observations of parasitoid larvae in multiparasitized caterpillars

Myl caterpillars were dissected in four conditionsFig. 3a) and parasitoid larvae were observedFig. 3b). NoCk larvae were observed inCk-ovipositedMyl caterpillars 8 days post-ovipositionFig. 3c). In the case of day 8-multiparasitizedMyl caterpillars, livingCk larvae were observed in 83.3% of caterpillars. Among these, 70.0% of caterpillars contained both livingCk and livingMp larvae whereas 13.3% contained onlyCk larvaeFig. 3c). NoCk larvae were observed in 16.7% of the caterpillars, whereas 3.3% contained onlyMp larva and the remaining 13.3% contained no parasitoid larvaeFig. 3c). In dead multiparasitizedMyl caterpillars from whichCk emerged, deadCk larvae were observed in 66.7% of the caterpillars, whereas the remaining caterpillars contained noCk larvae. NoMp larvae were observed in these cases. In dead multiparasitizedMyl caterpillars from whichMp emerged, deadCk larvae were observed in 86.7%, while the others contained no parasitoid larvae. Hyperparasitism, in whichCk larvae parasitize inMp larvae, was not observed (Fig. 3b).

Experiment 6: simultaneous free-oviposition rearing in cages

Of 10 replicates, 5 showed successful parasitism ofCk inMyl caterpillars (Fig. 4). Overall,Ck emerged from 6.0% ofMyl caterpillars. The number ofCk adults emerging fromMyl caterpillars was 21.6 ± 9.3 (mean ± SD).Mp emerged from 48.0% ofMyl. 22.0% of them pupate and another 22.0% died during experiments. Additionally, 2.0% ofMyl caterpillars disappeared during cage experiments.

Successful parasitism byC. kariyai in non-hostMy.loreyi parasitized byMe.pulchricornis

Attraction of parasitoid wasps to sympatric unsuitable host species and subsequent oviposition onto or into unsuitable hosts is widely documented. Females of the specialist endoparasitoid wasp,C.kariyai (Ck), also respond to chemical cues from unsuitable host species, including sympatricMy.loreyi (Myl), and exhibit oviposition behavior toward them^24,28,34,46. Our results demonstrate thatCk females recognizeMyl caterpillars and oviposit into them as into their usual host,My. separata (Mys) caterpillars (Experiment 1). However,Myl caterpillars parasitized solely byCk never producedCk adults (Experiment 2).

Remarkably, our multiparasitism experiments revealed thatCk can complete larval development inMyl caterpillars when these caterpillars are also parasitized by the naturally sympatric endoparasitoid wasp,Me. pulchricornis (Mp), which usesMyl as its usual host (Experiments 3 and 4). In essence,Ck can utilize unsuitable hostMyl caterpillars as hosts when multiparasitism withMp occurs. According to observations of parasitoid larvae in multiparasitizedMyl caterpillars, noCk larvae were found parasitizingMp larva (Experiment 5). Therefore, hyperparasitism (cf.⁶⁵), does not explain this phenomenon.

Ck females protect their eggs and their larvae from the immune response of their usual hosts,Mys caterpillars, by injecting polydnavirus (CkPDV) and venom^46,50,55,66. These maternal anti-immunity factors are effective againstMys caterpillars, but not against other caterpillars⁴⁶, which restricts the range of potential hosts forCk. In fact, althoughCk females oviposited 53.7–59.0 eggs intoMyl caterpillars (Experiment 1), noCk larvae were observed in hemocoels ofMyl caterpillars eight days post-oviposition (Experiment 5), and successful parasitism never occurred (Experiment 2). Similarly,Mp females introduce virus-like particles (MpVLPs) into host caterpillars along with a single egg, which then regulate the immune response of the host insects^51–53. Since 83.3% of multiparasitizedMyl caterpillars containedCk larvae eight days after oviposition, it is possible that maternal factors ofMp protect not onlyMp eggs and larvae, but alsoCk eggs and larvae, allowingCk larvae to survive inMyl caterpillars. However, identifying physiological mechanisms that allowCk to survive in unsuitable host caterpillars in multiparasitism remains a future challenge.

A series of studies by Magdaraog’s group^56–58 clarified intrinsic competition betweenCk andMp inMys caterpillars, which are ordinary hosts for both parasitoids. They demonstrated that multiparasitizedMys produce eitherCk orMp when the interval between the first and second oviposition is between 1 and 96 h, but the parasitoid species ovipositing first generally prevails over the other⁵⁶. For example, whenCk oviposited intoMys 1 h beforeMp, the successful parasitism rate ofCk was approximately 35%, which is significantly higher than that ofMp⁵⁶. In contrast, in our study, the successful parasitism rate ofCk in multiparasitizedMyl is significantly lower than that ofMp, regardless of oviposition order or host instar, with the maximum successful parasitism rate ofCk being only 20.0%, whenCk oviposited into 4th instarMyl caterpillars 12 h beforeMp (Experiment 4).

The outcome of intrinsic competition betweenCk andMp inMys was also mutually exclusive⁵⁶, as observed inMyl in this study, and is determined by three factors: resistance to the host immune response, direct conflict among larvae, and toxic effects of maternal anti-immunity factors (CkPDV, MpVLP or venom) on heterospecific parasitoid larvae⁵⁸. Our results showed that multiparasitized-Myl have the ability to produceCk when femaleCk ovipositedMyl caterpillars < 24 h beforeMp, or < 12 h afterMp. In cases in whichCk oviposited more than 48 h beforeMp,Ck eggs may have been killed by theMyl immune response beforeMp oviposition. Conversely, whenCk oviposited more than 48 h afterMp,Ck could not complete larval development becauseMyl caterpillars die soon afterMp emergence⁶⁷. This assumption is supported by observation of deadCk larvae insideMyl caterpillars from whichMp had emerged⁶⁷.

Kraaijeveld³¹ hypothesized that oviposition into sympatric, unsuitable host species by parasitoids could increase survival probability when the ordinary host species is absent, acting as a kleptoparasitoid by exploiting the anti-host immunity of another parasitoid species via multiparasitism. However, successful parasitism of a parasitoid in unsuitable host species when multipatrasitised with a naturally sympatric parasitoid had not been demonstrated previously^{31,32,42–44}. Our results present successful parasitism by a wasp in an unsuitable host through multiparasitism with a naturally sympatric parasitoid. Although the parasitism success rate byCk inMyl caterpillars multiparasitized withMp (< 20.0% ) was lower than that in the ordinary hostMys (> 70%^24,68), oviposition byCk females in unsuitable hostMyl caterpillars is clearly possible. Therefore, as Kraaijeveld³¹ predicted, oviposition of parasitoid wasps in unsuitable hosts can be adaptive, especially when females cannot find their ordinary hosts. For example, in the case ofCk in Japan, the ordinary host,Mys, cannot overwinter when the average winter temperature falls below 4 °C, so theMys population in spring is typically low. However, their numbers increase during summer and autumn due to mass migrations from China (Koyama & Matsumura⁶⁹ and its references). Under these conditions, temporary use of “non-host” species likeMyl, which occur stably throughout the year, may enhance the reproductive potential ofCk. Given that the parasitism rate ofMp on Myl in the wild can reach 42.9%⁴⁷, it is likely that multiparasitism withCk occurs. However, the emergence rate ofCk fromMyl in cage experiments (Experiment 6) was extremely low (6%), and currently, there are no records ofCk emerging fromMyl in the wild. The frequency of this phenomenon occurring in natural environments is likely extremely low, and further field investigations are required to document this interaction.

Pirate parasitism: introducing a new term

Over 100 years ago, Pemberton and Willard⁴³ discovered that the larval parasitoid waspTetrastichus giffardianus (Hymenoptera: Eulophidae), introduced into Hawaii from West Africa⁷⁰, could use a local, unsuitable host, the Hawaiian fruit fly,Bactrocera cucurbitae (= Dacus cucurbitae) (Diptera: Tephritidae), only when the fruit fly larva was previously parasitized by another parasitoid,Psyttalia fletcheri (= Opius fletcheri) (Hymenoptera: Braconidae), also introduced to Hawaii from India⁷¹. Based on this study, Askew⁷² called this phenomenon “obligatory multiparasitism”, without providing a definition. On the other hand, today, the term “obligatory multiparasitism” (or obligate multiparasitism) is also used to describe a phenomenon observed in species such asPseudorhyssa (Hymenoptera: Ichneumonidae) orEurytoma (Hymenoptera: Eurytomidae)^73,74. These wasps parasitize insects hidden in hard materials, such as timber or thick cocoons, as their hosts. However, they cannot drill through these materials themselves to reach the hosts. Therefore, these parasitoids attack hosts previously oviposited by another parasitoid by following an oviposition hole in the material created by the previous parasitoid. This behavior is often termed “obligate multiparasitism”^73,74. Consequently, the term “obligatory parasitism” currently connotes parasitism that cannot be completed without the help of oviposition by another parasitoid.

To avoid confusion, we propose a redefinition of the term “obligatory parasitism” and introduce a new term, “pirate parasitism” (Fig. 5). We redefine “obligatory multiparasitism” as kleptoparasitic parasitism by a parasitoid that requires oviposition by another parasitoid species to attack the host and/or complete development in/on the host body post-oviposition. In the latter case, as a subclass of obligatory multiparasitism, we propose a new term, “pirate parasitism”, defined as parasitism by parasitoids that necessitates prior parasitism by another parasitoid species, resulting in complete development through multiparasitism. We also propose referring to parasitoids that require multiparasitism to utilize an “unsuitable host” as “pirate parasitoids.” We call those parasitoid wasps that facilitate pirate parasitoids as “mediators” (Fig. 5).

In the case of the host/parasitoid system in our study,C.kariyai is a specialist parasitoid onMy.separata, but can utilizeMy.loreyi through “pirate parasitism” when multiparasitism withMe.pulchricornis occurs. In this case,C.kariyai is the “pirate parasitoid”, andMe.pulchricornis is the “mediator.”Meteorus pulchricornis, suffers a disadvantage due to pirate parasitism. However, there may also be cases of pirate parasitism in which the mediator suffers no disadvantage.

The ecological and evolutionary significance of the response and oviposition in unsuitable host species

The concept of pirate parasitism indicates that attraction to, acceptance of, and oviposition by parasitoids on unsuitable host species increases reproductive potential. If parasitoid wasps were only attracted to their customary hosts, their reproductive success would be reduced to zero whenever their usual host was absent. However, with pirate parasitism, parasitoids can oviposit in unsuitable hosts, thereby maintaining some reproductive potential and increasing their fitness. Specialist parasitoid wasps, in particular, are more likely than generalist parasitoids to encounter environments in which their hosts are absent. Therefore, reproducing via pirate parasitism might significantly increase their reproductive potential. This suggests that the seemingly maladaptive behavior of parasitoid wasps ovipositing in non-hosts may actually represent an adaptive behavior. In fact, many species of parasitoids are attracted to and oviposit not only in sympatric unsuitable hosts, but also in introduced unsuitable hosts (Kruitwagen et al.,⁷⁵ and references).

The concept of pirate parasitism is also important from the perspective of evolution of parasitoid host ranges. Host shifts and host range expansions of parasitoid wasps have been thought to occur through a process in which wasps accidentally oviposit in unsuitable host that they had not previously used^2,37–39. If development is successful in unsuitable hosts, newly emerged wasps learn the smell of that new host or its habitat, and subsequently show a preference for oviposition on it. The fact that our research results indicate that oviposition in unsuitable hosts can increase reproductive success implies that such oviposition behavior can serve as preadaptation in the context of host shifts and host range expansions in parasitoid wasps. This could increase the likelihood of the aforementioned “happy accident.”

Multiparasitism is also generally considered maladaptive for parasitoids as it reduces the likelihood of successful parasitism due to direct or indirect competition between parasitoid species⁷⁶. However, in the case of pirate parasitism, a pirate parasitoid increases its fitness through multiparasitism. This suggests that female pirate parasitoids can identify and preferentially oviposit in unsuitable hosts that have already been parasitized by mediators, but this possibility remains to be verified.

Even though multiparasitism is thought to occur frequently in the field, it is difficult to detect by host collection and rearing because in most cases, only one parasitoid species emerges from the host⁷⁶. Future studies need to investigate the presence, frequency, and generality of pirate parasitism in parasitoid-host systems by detecting multiparasitism using molecular tools with species-specific primers, as recently used for detection of hyperparasitism^77,78 and laboratory multiparasitising experiments.

Insects

Mythimna separata andC.kariyai were obtained from stock cultures in the Laboratory of Applied Entomology and Zoology, University of Tsukuba, Japan. Caterpillars ofMythimna loreyi were collected from maize and sorghum fields in Kimotsuki-cho, Kanoya City and Kagoshima City, Kagoshima Prefecture, Kyushu, Japan, between July 28 and 30, 2020. The original colony ofMeteorus pulchricornis was obtained fromM. separata caterpillars collected in the field, as described above. BothMys andMyl colonies were reared on an artificial diet (Silkmate^® 2 S, Nosan Corporation, Yokohama, Japan) in the laboratory (25 ± 1 °C, 16 L: 8D photoperiod and 60 ± 10% RH) following methods forMys described in Fukushima et al.⁷⁹ and Magdaraog et al.⁵⁶ under the same conditions as the herbivores. Populations of both parasitoid species have been maintained using 3rd instarMys caterpillars as hosts under laboratory conditions. ForCk, three to five-day-old mated, naïve females were used for all experiments. Because theMp strain we used was an apomictic thelytokous strain (cf. Fujie et al.,⁸⁰; Wachi et al.,⁸¹), unmated, 7-10-day-old females were used for all experiments.

Experiment 1: host acceptance and oviposition

Female parasitoids with no oviposition experience were used for the experiment. Each female parasitoid was placed individually in a Petri dish (5.3 cm diameter, 1.5 cm height) containing wet cotton 30–60 min prior to the experiment. A single caterpillar was then introduced into the Petri dish, and parasitoid’s behavior was observed for 10 min. Whether the parasitoid attacked the caterpillar was recorded. Throughout experiments in this study, oviposition was confirmed by observing a single insertion and withdrawal of the ovipositor from the caterpillar. ForCk, 3rd, 4th or 5th instar unparasitizedMyl caterpillars orMyl caterpillars previously oviposited byMp were offered. Similarly, 3rd, 4th or 5th instar unparasitizedMyl caterpillars orMyl caterpillars previously oviposited byCk were offered toMp. ParasitizedMyl caterpillars used for these experiments were prepared by single oviposition by parasitoids ca. 1 h before experiments. As a positive control forCk oviposition, 4th instar, unparasitizedMys caterpillars (ordinary host forCk) were also offered.

To confirm the presence of parasitoid egg(s) in the caterpillar body, caterpillars were dissected within 30 min after oviposition using the method of Aikawa et al.³⁴. Numbers of parasitoid eggs in the caterpillar were recorded. Dissected caterpillars were observed under a binocular stereo microscope (SMZ 1270, Nikon, Tokyo, Japan).

Experiment 2: single-parasitism experiments

Host suitability ofMyl caterpillars for the two parasitoids when each parasitoid oviposited alone was determined. Parasitoids with no prior oviposition experience were allowed to oviposit into 3rd, 4th or 5th instarMyl caterpillar in a Petri dish. The oviposited caterpillar was then transferred into a plastic container (100 mm in diameter, 40 cm in height, Sansho, Tokyo, Japan) and reared individually with artificial diet until the parasitoid emerged, the caterpillar pupated, or the caterpillar died.

Experiment 3: multiparasitism experiments in different host instars

To examine successful parasitism ofCk inMyl caterpillars parasitized withMp, the outcome of multiparasitism with both parasitoids in 3rd, 4th or 5th instarMyl caterpillars was observed. MultiparasitizedMyl caterpillars, with oviposition byCk andMp in either order in < 15 min, were prepared using methods described for Experiment (1). Parasitized caterpillars were reared individually, and outcomes were recorded as described for Experiment (2). WhenCk emerged fromMyl caterpillars, to verify their reproductive ability, five newly emerged female adults from each treatment were allowed to oviposit into their usual host,Mys, after mating. ParasitizedMys caterpillars were reared individually as described above, and outcomes were recorded using the methods described in the single-parasitism experiment section.

For positive control forCk parasitism, 4th instarMys was also offered toCk and ovipositedMys caterpillars were reared individually as same asMyl caterpillars. Then, the number of parasitoids per caterpillar was counted.

Experiment 4: multiparasitism in different sequences and intervals

To examine effects of the order and timing of oviposition by the two parasitoid species on outcomes of multiparasitism inMyl caterpillars, 4th instar caterpillars parasitized by the two parasitoid species in different sequences and intervals were reared. Both parasitoids were allowed to oviposit into caterpillars in either order of oviposition, at intervals of < 10 min, 12 h, 24 h, and 48 h. Parasitized caterpillars were reared individually, and outcomes were recorded using methods described above.

Experiment 5: observation of parasitoid larvae in multiparasitized caterpillars

Based on results of multiparasitism experiments, multiparasitizedMyl caterpillars produced not onlyMp, but alsoCk. To ascertain whether hyperparasitism occurred involving the two parasitoid species in the sameMyl caterpillars, multiparasitizedMyl caterpillars were dissected and parasitoid larvae in the caterpillars were observed. Multiparasitized 4th instarMyl caterpillars, which were oviposited byCk followed byMp within < 10 min, were prepared using methods described previously. Parasitized caterpillars were reared on artificial diet. Caterpillars were dissected in 70% ethanol-water solution before parasitoid emergence (on day 8 after oviposition) or within 12 h after parasitoid emergence to observe the presence or absence of parasitoid larvae, and whether hyperparasitism occurred between the two parasitoid species. Additionally,Myl caterpillars oviposited byCk alone were also dissected on day 8 after oviposition to determine whetherCk larvae survived inMyl. All observations were conducted under a binocular stereo microscope (SMZ 1270, Nikon, Tokyo, Japan).

Experiment 6: simultaneous free-oviposition rearing in cages

To examine whetherCk could emerge fromMyl in an environment in which it could freely oviposit, we created a rearing cage in whichCk,Mp, andMyl coexisted and evaluated the emergence rate ofCk fromMyl. This experiment was conducted in transparent plastic containers (17 × 19 cm, 29 cm high). Maize (“Honey-Bantam Peter 610”, Sakata Seed Co., Japan) was utilized as the host plant forMyl caterpillars. Maize plants were cultivated from seed in plastic flowerpots (14.0 cm diameter, 11.5 cm height) in a greenhouse (25 ± 1 °C, 16 L:8D photoperiod)⁸². Stems of 3- to 4-week-old maize plants containing 3–4 leaves, approximately 25 cm high, were cut and placed in a 50-mL beaker filled with water. Maize leaves were placed at the center of the container, and ten 4th instarMyl caterpillars were placed on the leaves. Three females each of bothCk andMp were released into the container. Honey and wet cotton were provided in the container for the wasps. These containers were maintained in a rearing room (25 ± 1 °C, 16 L: 8D photoperiod and 60 ± 10% RH) for 48 h. All caterpillars were then collected from the container and reared individually, and outcomes were recorded using the same methods described in the singleparasitism experiment section.

Statistical analysis

For experiment 1, differences in host acceptance rates of parasitoids among treatments were evaluated with Chi-square tests, and differences in numbers of eggs oviposited in caterpillars among caterpillar conditions were evaluated using analysis of variance (ANOVA). For experiment 2, the successful parasitism rate among host instars was evaluated with Chi-square tests. In experiment 3, the significance of the emergence percentage of the two wasps in each host instar and order of oviposition was analyzed using binominal tests. The successful parasitism rate ofCk among host instars and the order of oviposition were evaluated with Chi-square tests. Mean numbers ofCk adults that emerged from caterpillars were evaluated using Tukey-Kramer honestly significant difference (HSD) tests after ANOVA. In experiment 4, the successful parasitism rate ofCk by order and interval of oviposition was evaluated with Tukey’s wholly significant difference (WSD) tests after Chi-square tests, and mean numbers ofCk adults emerging from caterpillars were evaluated using Tukey-Kramer HSD tests after ANOVA. All analyses were performed in R v. 4.0.3 software⁸³ and Tukey-Kramer HSD tests and Tukey WSD tests were performed using an open-source package (http://aoki2.si.gunma-u.ac.jp/R/m_multi_ comp.html). Since experiments 5 and 6 were qualitative experiments, statistical analyses were not conducted.

Competing interests

The authors declare no competing interests.

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Supplementary Materials

Data Availability Statement

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.