Two’s company, three’s a crowd: population density and food availability affect katydid courtship

doi:10.21203/rs.3.rs-7448537/v1

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Two’s company, three’s a crowd: population density and food availability affect katydid courtship

https://doi.org/10.21203/rs.3.rs-7448537/v1

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Animals are predicted to vary their investment in mating behaviors depending on the availability of resources, but there is much to be discovered about the underlying mechanisms. Chloroscirtus discocercus is a Neotropical katydid that makes unusually large investments in mating behaviors, a situation where changing mating behavior according to environmental conditions may be advantageous. In this experiment, varying food availability and population density revealed that changes in the environment influenced the strategies that males used to attract mates. Well-fed high density males called less and moved more, suggesting a switch from acoustic mate attraction to active mate seeking tactics. These findings suggest katydids make use of flexible courtship strategies in response to changing environmental conditions and shed light on how populations might respond to changing environmental conditions.

Bioacoustics

behavioral plasticity

calling rate

calorie intake

population density

reproductive behavior

Environmental factors play an important role in mating strategy. Many animals respond to fluctuations in environmental conditions with altered behavior (Charmantier et al. 2008; Gross et al. 2010; Moczek 2010; Gage 1995; Zahavi 1977). Responsiveness to internal and external conditions can be considered along a spectrum, with one end exemplified by highly plastic responses that track variations in the environment, and the other extreme characterized by biological robustness, allowing behavior to stay constant under variable conditions (Kitano 2004). Where a particular species lies on this spectrum likely depends on the environmental context and the life history of the organism. It is important to understand the mechanisms with which animals respond to different environmental conditions in order to deepen our understanding of species’ life history and to gain insight on how different species may respond in a changing world (Thornes 2016). Many environmental conditions might interact with behavioral strategy. In this study, we focus on two important contextual variables: calorie availability and population density (Mattei et al. 2010; Kokko & Rankin 2006; Martin et al. 2008; Gage 1995).

Calorie availability influences most if not all species on Earth (Paine 1971) and can mediate critical behaviors, including reproduction (Martin et al. 2008; Given 1988). Many behaviors associated with reproduction require significant caloric investments, such as stridulation or spermatophore creation (Symes et al. 2015; Andersson and Iwasa 1994; Given 1988; Gwynne 1988). Empirical examples show that the physical condition of an individual often dictates behavioral responses such as which sex is choosier and whether males invest in parental care (Kokko & Rankin 2006; Barta et al. 2002; Wearing-Wilde 1996). The condition-dependent signaling hypothesis posits that animals will adjust investment in signaling according to internal physiological conditions in order to maximize fitness trade-offs between survival and reproduction (Penn & Szamado 2020; Zahavi 1977). While the condition-dependent signaling hypothesis is specific to signaling, other high-investment strategies for enhancing mating success, such as mate searching or territory defense, could also follow the same logical framework that tracks availability of energy. We therefore predict that animals will minimize their investments in mate searching and signalling in response to scarcity of calories.

Population density can also have profound impacts on animal mating behavior (McCartney et al. 2012; Mattei et al. 2010; Kokko & Rankin 2006; Gage 1995). Higher density populations can result in increased male-male competition for access to females (Mattei et al. 2010; Kokko & Rankin 2006), driving the evolution of costly sexual traits for competition. In such situations where males compete for females, females are generally considered choosier and seek out more desirable traits (Kokko & Rankin 2006). Low-cost mate searching and competition encourage investment in costly traits (McCartney et al. 2012; Mattei et al. 2010; Kokko & Rankin 2006; Gage 1995). However, in some systems, increased competition may beget interference and can decrease reproduction, therefore driving the population density lower (Kokko & Rankin 2006). In low density contexts, mate-searching costs increase and selectivity decrease based on limited availability of mate choices (Kokko & Rankin 2006). Operational sex ratio (OSR) is also known to influence mating behavior and can further increase competition in the sex that is presently abundant (Bateman 1997). Because male competition is a common driver in these interactions, we test the hypothesis that male signaling rate and investment in mate searching will increase in environments with more competing individuals. We predicted that females would take a more active role in mate-searching in low density environments due to lack of options.

Katydids (Orthoptera: Tettigoniidae) are a useful system for investigating how reproductive behaviors are affected by environmental factors because reproductive costs can be very high. Animals that make larger investments may benefit from greater behavioral flexibility because the larger an investment is, the greater the consequences if the individual does not receive proportionate returns on that investment. Male katydids provide a spermatophore during mating, a costly nuptial gift that in some species can be over 40% of a katydid’s weight (McCartney et al. 2012). Males who pursue mating should be in good physical condition to produce such a gift (del Castillo et al. 2007). Mate searching is also costly in the Neotropical rainforest because of high levels of competition and predation (Symes et al. 2021; ter Hofstede et al. 2017; McCartney et al. 2012). Orthopterans provide easily quantifiable acoustic signaling in mating interactions to help to facilitate mate searching that make them ideal for studying mating interest (Haskell 1958). The subfamily Phaneropterinae is especially useful to assess investment in reproductive behaviors due to the nature of female response; females invest in mate searching and duet acoustically with males (Heller et al. 2015; McCartney et al. 2012), albeit not producing calls with the complexity of male signals. Little is known about how mate searching efforts are divided between sexes, but in light trap captures on Barro Colorado Island, the phaneropterine C. discocercus is normally found at approximately 1:1 sex ratio (54% of 362 individuals were found to be male), an unusually equal ratio for light trap data (Symes et al. 2021). This would suggest there is a relatively equal investment in mate searching from both sexes, so we test the hypothesis that male and female C. discocercus move in relatively equal amounts, a diversion from the norm that males are the ones doing the mate searching. Many reproductive systems see a reversal of expected sex roles in courtship precipitated by changes in diet, sex ratio, and population density (Kokko and Rankin 2006; Wearing-Wilde 1996; Gwynne & Simmons 1990).

To evaluate these hypotheses and the role of environmental variation in shifting sex roles, we manipulated population density and diet in controlled mating trials of the phaneropterine C. discocercus and observed the impact on behavior, specifically male and female movement, approaches of the opposite sex, and male calling activity. We test the hypothesis that male signaling rate and investment in mate searching will increase when more individuals are present. We predicted that male investment in reproductive behaviors would increase with calorie and population density, due to greater access to resources and elevated male-male competition. We predicted that females would take a more active role in mate-searching in low density environments due to lack of options.

1. Specimen collection

We collected a total of 85 adult female (N = 47) and male (N = 38) C. discocercus (Phaneropterinae: Tettigoniidae) from building lights at the Barro Colorado Island (BCI) field station in Panamá (9.1648° N, 79.8366° W) between June 21st and July 27th in 2022 (22 individuals) and June 15th to August 21st in 2023 (63 individuals). We turned on field station lights at approximately 1800 hours each evening and collected katydids nightly at approximately 2200 hours and in the morning at 0500 hours using plastic cups and collection nets.

2. Housing and diet

After capture, we placed katydids in mesh cages of 32 cm x 32 cm x 32 cm and labelled them using numbered red, white, or green plastic tags glued to the dorsal pronotum with Krazy Glue brand adhesive (6655 Peachtree Dunwoody Road, Atlanta, GA). We took special care to not adhere the antennae, wings, or stridulatory apparatus. We recorded plastic tag numbers for each individual with sex (identified by presence or absence of ovipositor), length (from the tip of the head to the end of abdomen), and mass (using an OWAY digital pocket scale with 0.001 mg precision). We housed katydids with Exo Terra Forest Moss (305 Forbes Blvd., Mansfield, MA) or paper towel substrate. We sprayed the substrate with water daily to ensure a constant supply of drinking water and air moisture. Both sexes were able to hear each other during the day. Females lived together when not in trials and always had access to ad libitum water and apple (generally around double the low diet portion). Males were housed separately from females with two to four males to a cage and were kept on either high or low diet treatments. High diet males ate the same diet as females. We gave low diet males approximately 0.3 g of apple every two days. The apple portions may not have always been equally shared by males. We observed a fight between two low diet males competing for food near the end of the study period, showing that the katydids were indeed food-limited. We implemented diets for a minimum of 48 hours before trials began in order to ensure previous nutrient intake was completely out of the system at the time of behavioral testing. Observationally, subjects that were deprived of food for longer than this began to display high mortality rates, indicating that existing energy reserves were depleted. There was no maximum time period for katydids to be on their treatment. We weighed male katydids daily in 2022 (Supplemental Table 1) to evaluate the effectiveness of the protocol. The same protocol was followed in 2023 with the exception that daily weights were no longer collected to minimize handling stress.

3. Mating trials

For mating trials, katydids were placed in the same mesh enclosures with each containing trios consisting of one female plus two males from the same diet treatment. Keeping katydid trios in individual cages allowed us to track individual responses while creating acoustic groupings of different sizes. Trio compositions were never duplicated two nights in a row and we tried to keep groupings as different as possible from night to night. We manipulated group size by altering the number of enclosures, and therefore trials consisted of a total of either three, six, nine, or 12 katydids (one, two, three, or four enclosures). The group size was determined based on the number of available katydids each night, meaning larger trials tended to coincide with collections around the new moons. This timing enabled us to collect data within a few days of capture. The data for each individual katydid were extracted from the first trial in which they were used (or the first successfully video recorded trial in case of video failure). Focusing on the initial trial, helped to standardize the amount of time that insects were in captivity and on a diet treatment when data were collected. During the trials, the females had access to the diet of the males with which they were paired. We formed trios at approximately 1630 hours on the day of the mating trial and gave a minimum of 2.5 hours for insects to acclimate to the enclosure and recover from handling.We set enclosures outside by 1800 hours every evening and they were not moved or disturbed until the mating trial concluded. Behavioral trials began at 1900 hours and concluded at 2200 hours, a period of high acoustic activity (Symes et al. 2024). Each enclosure was sampled twice per night using audio and video recording [Canon EOS Rebel T3i or Canon EOS T100/4000D (1 Canon Park, Melville, NY)] and the timing of each sample was selected using an online random time generator. Depending on the availability of recording equipment, we either recorded each cage at separately generated times or recorded all cages simultaneously with independent sets of equipment. We scored behavior of focal individuals using the video and audio tracks from the recording. In some trials, supplemental audio recordings were captured with TASCAM DR-40 Linear PCR recorders (10410 Pioneer Blvd., Unit #1, Santa Fe Springs, CA), and in these cases the TASCAM recording was used for the audio analysis. Recordings lasted from seven to 12 minutes, varying haphazardly each night. A total of 53 trials were run (15 nights in 2022 and 38 in 2023). We used data from 24 video trials: 19 from 2022 and 19 from 2023. In each case, we scored only the first video in which a katydid appeared, although they may have been used as a non-focal male in later videos.

4. Behavioral Scoring

We used video and audio recordings to score movement, approaches, and calls. To minimize observer bias, blinded methods were used when all behavioral data was scored. We identified females by either color of tag or presence of ovipositor. We identified individual males by comparing data for body length and mass for both individuals in each enclosure. For both sexes, movement was defined as the time interval between when a katydid started moving to the time that it stopped for more than two seconds. A change in the angle a katydid was facing was classified as movement even if there was no change in location. We divided the number of seconds the katydid spent moving per video recording by the number of seconds in the video recording to calculate the proportion of time spent moving for each individual. In addition, we quantified the number of approaches in each video recording. Approaches were defined by one sex coming within its body’s length distance of the opposite sex for at least three seconds, whether these seconds consisted of a full stop or a noticeable reduction in speed, minimizing the scoring of events where individuals incidentally crossed paths. The approach was attributed to the individual moving; if both individuals moved towards each other, two separate approaches were recorded. The number of approaches was divided by the number of minutes in the video to quantify the approach rate for each individual.

We analyzed the audio recordings for acoustic events using Raven Pro 1.6.4. Each call was defined as a multi-pulse acoustic emission from a male katydid that was separated from other events by at least 50 milliseconds. These calls are spectrally differentiated from the “ticks” that both males and females produce; complex calls from C. discocercus contain 6.4 ± 0.5 pulses on average while a tick generally contains one pulse (ter Hofstede et al. 2020). Calls were attributed to a specific male katydid in the video by noting visible wing shaking associated with stridulation and sound production. We did not include ticks because the wing shaking was unreliable for identifying which individual produced the signal. Furthermore, those complex calls that did not have a clear identification to an individual were excluded. We could confidently attribute calls to individuals at least 95% of the time in all group sizes and diet treatments. The number of calls was divided by the number of minutes in the video to quantify the call rate for each individual (Supplemental Table 2).

5. Statistical analysis

To test the efficacy of the diet treatments, we used a linear mixed-effects model on regularly collected body masses from seven males in the high and low diet treatments in 2022 with individuals as a random effect. We then used multiple linear regression to examine the effects of group size, diet, and sex on call rate, movement rate, and number of approaches to determine which environmental factors were correlated with behaviors. We used a multiple linear regression to determine the effects of diet and group size on calling rate with a sample size of 35 male individuals. Each individual’s data included the group size and their own call rate. We used a link function of log (y + 1) in the model to adjust for nonnormality and lack of equal variances in the data. We then evaluated the factors affecting movement with a multiple linear regression to determine the effects of group size, diet, and sex on movement rate with a sample size of 57 individuals (35 male and 22 female). We used a link function of log (y + 1) to meet assumptions for the test as well. Finally, we tested for a correlation between time spent moving and number of approaches to see if movement is a good metric for interest in mating. We used a Spearman rank correlation to assess the association between the rate of movement and the number of approaches to account for non-normality of data. Code may be referenced in the supplementary data as “Project Code 2024”. All statistical analyses were performed using R Studio Version 4.22.

6. Ethical note

We kept katydids in captivity for up to 10 weeks for the duration of the study. Individuals were always mature adults. Because C. discocercus is abundant on Barro Colorado Island, we anticipated minimal population impacts. Labelling katydids lasted for a period of up to five minutes, and the handling caused notable stress to most individuals, including regurgitating food. We performed handling and weighing as little as possible to minimize stress. Many katydids died during the study due to what seemed to be either old age or parasitoids brought in from the wild (this was especially prominent in males during the 2023 period of study). Those who survived to the end of the study were released back into vegetation. Research activities on Barro Colorado Island are conducted by permission of the Smithsonian Institution, through agreement with the Republic of Panama. All necessary permissions were obtained as part of the research visit approval.

1. Diet Treatment Test

We used a linear mixed-effects model to test male katydid mass as a function of days on either the high or low diet treatment. Individual katydid ID was used as a random effect. The test revealed that katydid mass changed over time, depending on what diet treatment individuals were on (Fig. 1). Katydids on low diet tended to not gain weight (ß = -0.0004, SE = 0.0009, t_181.6 = -4.27, p < 0.001), while katydids on high diet gained weight (ß = 0.0028, SE = 0.0007, t_181.9 = 4.18, p < .0001).

2. Factors Contributing to Call Rate

Multiple linear regression was used to test if male call rate was affected by group size and diet treatment. We used a link function of log (y + 1) in the model to adjust for nonnormality and lack of equal variances in the data. The fitted regression model (Fig. 2) was:

(1) Call Rate = 1.28–0.11(Group Size) – 1.26(Diet) + 0.15(Group Size) (Diet)

While the overall regression for male call rate (Fig. 2) was not significant (R² = 0.176, t_3,31 = 2.132, p = 0.117), many of the predictors revealed significant relationships in the data. Group size had a negative main effect on call rate (ß = − 0.113, SE = 0.049, t_3,31 = − 2.29, p = 0.030). Diet treatment also had a negative effect (ß = − 1.261, SE = 0.521, t_3,31 = − 2.42, p = 0.022). We found the interaction term between group size and diet predicted call rate (ß = 0.145, SE = 0.065, t = 2.23, p = 0.033), showing that the effect of group size on calling rate differed by diet treatment. We found that high diet males called less as group size increased, while low diet males called slightly more as group size increased.

3. Factors Contributing to Time Spent Moving

Multiple linear regression was used to test if group size and sex of the individuals significantly predicted movement rate. We used a link function of log (y + 1) in the model to adjust for nonnormality and lack of equal variances in the data. The fitted regression model (Fig. 3) was:

(2) Movement Rate = 0.58–0.05(Group Size) – 0.57(Sex) + 0.08(Group Size) (Sex)

The overall regression for movement (Fig. 3) was significant (R² = 0.189, F_3,53 = 4.029, p = 0.012). Group size had a negative main effect on movement (ß = − 0.045, SE = 0.017, t = − 2.63, p = .011). Sex had a significant main effect, as well (ß = − 0.569, SE = 0.177, t = − 3.22, p = .002). The interaction between group size and sex was also significant (ß = 0.076, SE = 0.022, t = 3.47, p = .001), indicating that the effect of group size on movement depended on the sex of the individual. Female katydids moved less as group size increased, while males moved more in larger groups.

4. Relationship Between Movement and Mating Interest

Individuals who spent more time moving were also approaching and interacting with members of the opposite sex more often (ß = 0.256, SE = 0.041, t₅₄ = 6.29, p < .0001) (Fig. 4).

Environmental variability is a pervasive feature of natural environments. In this study, we explore two major ways in which environments can vary in order to understand if and how organisms respond. We focused on a species where mating costs are high, both in terms of predation risk as well as physiological investment. We tested the prediction that the katydid C. discocercus would shift their investment in acoustic signaling and other mating behaviors in response to changes in calorie availability and population density. We found that diet and group size were both important factors in predicting proportion of time spent moving, the frequency of approaches between potential mates, and male call rate. We found that C. discocercus katydids showed phenotypic plasticity in response to population density and diet, indicating that these variables are important for resource maximization strategies.

We found a significant interaction between diet and group size (Fig. 2), where male call rate decreased with increasing group size in high diet katydids, while call rate increased slightly with an increase in group size in calorie-deprived katydids. Mating behaviors are calorically expensive (McCartney et al. 2012), so, unsurprisingly, calories played a component in predicting behavior. It is more surprising that call rate decreased as group size increased in the high diet treatment. We had originally predicted that increased male-male competition and high caloric stores would promote mating behaviors like acoustic signaling. However, we found that males only move more, not call more, in high density environments (Fig. 3). The lower calling rate in high diet males may be due to males prioritizing searching rather than calling when density is high. Utilization of phonotaxis in larger groups may become more difficult when there are more individuals to track. This result provides support for the condition-dependent signaling hypothesis, as katydids are changing signaling rates based on dietary status (Penn & Szamado 2020; Zahavi 1977).

The population density was found to predict time spent moving, mediated by sex (Fig. 3). As the group size of the mating trial increased we saw that males tended to move more, and females moved less. Movement was also shown to be correlated with more approaches between members of the opposite sex (Fig. 4), suggesting that the proportion of time spent moving might be a good measure of mating interest in some scenarios. Our method of scoring approaches, based on change in movement rate and proximity,minimized the scoring events where individuals incidentally crossed paths. Additionally, we observed that approaches would often result in individuals remaining in close proximity for an extended period of time, often accompanied by calling. This is not the first described instance of sex-specific mate searching strategies that vary with environment (Gage 1995, Kokko & Rankin 2006). Males may have moved more in larger groups because of elevated male-male competition, or because females reduce searching behavior, remaining stationary and evaluating males. When females remain stationary, it may also reduce localization confusion that would arise from many individuals that were both producing sound and moving. The results suggest it may be advantageous to katydids to adjust their movement in sex-specific strategies based on the population density in the direct vicinity.

It is important to note that the structure of the groupings is important for contextualizing these results. Initially, we observed that katydid calling rates were low when only a male and female were paired, but we observed increased signaling behavior with groupings that had two males instead of one during the pilot experiment. These higher signaling rates prompted us to proceed with trios containing two males. We did not add a second female because it was too difficult to consistently visually differentiate between four individuals in each video and we were interested primarily in the male signaling rate. Sex ratios may vary in the wild and govern various mating dynamics (Mattei et al. 2010; Kokko & Rankin 2006; Wearing-Wilde 1996). While it is important to note the ratio used here was male-biassed, the females used had been isolated from males for several days without the opportunity to mate, meaning that the operational sex ratio of males to receptive females was perhaps more similar to natural environments than if the number of receptive females had matched the number of males. While manipulating group size by adding additional enclosures of three allowed us to maintain ease of tracking individuals and kept diet treatments separate, we note that it could have affected behavioral dynamics if individuals were searching without being able to approach or see other individuals who were calling nearby. In nature, however, these animals often interact in dense vegetation where mate localization takes time and complex habitats, obstacles, and extended searching are not uncommon (Robinson & Hall 2002).

In both of the main interactions that we found during this study, group size was an important variable for predicting behaviors. Changes in behavior in response to group size may allow katydids to maximize fitness in a variety of contexts. One of the ways in which behavioral plasticity based on population density might benefit katydids is if they become more reproductively active around food sources. Other insects take advantage of aggregations around food sources to facilitate mate searching (Hartbauer et al. 2014), which could particularly benefit C. discocercus since mate searching is difficult in the Neotropics (Symes et al. 2021; ter Hofstede et al. 2017; McCartney et al. 2012). Digestive content analysis revealed that most katydid species on Barro Colorado Island do not specialize on specific plant species, but may prefer new growth across a wide variety of plant species and aggregate around these (Palmer et al. 2022). Furthermore, there is an increasing amount of evidence that plant volatiles, used often to aid in foraging for insects, are being used concurrently as a means of finding mates in a timely and efficient manner (Xu & Turlings 2018). Conversely, we found that high diet katydids tended to call more at low densities, suggesting that calling may serve as a mate-searching technique for solitary katydids.

The finding that the katydid C. discocercus responds to changes in the environment has interesting implications for further studies. We chose katydids as our study system because we speculated that species with higher investment in reproduction may be more likely to exhibit behavioral plasticity. Because this hypothesis was supported, it would be worth evaluating plasticity across related species with a broader range of mating costs to test the specific hypothesis that higher investment begets more flexibility. While our hypothesis is different from the existing condition-dependent hypothesis in that it incorporates behaviors in addition to signalling and extends to the external condition of population density, it builds on a similar framework (Penn & Szamado 2020; Zahavi 1977). Given that well-fed individuals call less as group size grows, it would be valuable to investigate whether aggregations occur naturally in the wild, such as around new vegetation and other transient food sources. If individuals are not uniformly distributed through the environment, it will be important to apply caution when inferring density from acoustic recordings of this and other insect species. In addition, it would be valuable to test the role of plant volatiles beginning with evaluating whether volatiles attract katydids in the wild. Future studies might also consider manipulating protein in the diet. This study only manipulated calorie intake, while protein may be more important in spermatophore creation or physical condition (Gwynne 1988). Manipulating protein and other components of the diet could provide more mechanistic insight into the changes in mating behavior, and could shed light on the conditions in the wild that could precipitate the responses documented in the lab. Further insight into how C. discocercus responds to the environment will allow us to discover the biological underpinnings of how they respond to variation in the environment, including the consequences for individual signaling rate, an important parameter for interpreting acoustic data (Symes et al. 2022). As extreme changes in the environment become more prevalent, the study of phenotypic plasticity and robustness becomes increasingly important to understand sensitivity and resilience.

STATEMENTS AND DECLARATIONS

The authors have no competing interests to declare that are relevant to the content of this article.

FUNDING

We are grateful to the Smithsonian Bat Lab for its support of this project. Special thanks to Melissa Caño and Isis Ochoa of STRI and all the guards at the Gamboa Laboratory and Barro Colorado Island. HH also thanks the Entomology Department and Cole Gilbert at Cornell University for advising on HH’s senior honors thesis, which served as a pilot project for this paper. Thank you to Maxwell Cantelmo for his intellectual contributions and logistical assistance, to Philip Hamann, Janet Hamann, Rémi Mauxion, and Ciara Kernan for crucial support with katydid collection and husbandry, and to Andrew Siefert from the Cornell Statistical Consulting Unit for key assistance with the analysis.

Author Contribution

(CRediT guidelines) HEH contributed to conceptualization, data curation, formal analysis, funding acquisition, investigation, project administration, software, validation, visualization, writing – original draft, and writing – review & editing. LBS contributed to project administration, resources, software, supervision, validation, and writing – review & editing. RAP contributed to project administration, resources, supervision, validation, and writing – review & editing.

Acknowledgement

We are grateful to the Smithsonian Bat Lab for its support of this project. Special thanks to Melissa Caño and Isis Ochoa of STRI and all the guards at the Gamboa Laboratory and Barro Colorado Island. HH also thanks the Entomology Department and Cole Gilbert at Cornell University for advising on HH’s senior honours thesis, which served as a pilot project for this paper. Thank you to Maxwell Cantelmo for his intellectual contributions and logistical assistance, to Philip Hamann, Janet Hamann, Rémi Mauxion, and Ciara Kernan for crucial support with katydid collection and husbandry, and to Andrew Siefert from the Cornell Statistical Consulting Unit for key assistance with the analysis.

Data Availability

Data is provided within supplementary information files.

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No competing interests reported.

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Two’s company, three’s a crowd: population density and food availability affect katydid courtship

Status:

Version 1

Abstract

Figures

INTRODUCTION

METHODS

2. Housing and diet

3. Mating trials

4. Behavioral Scoring

5. Statistical analysis

6. Ethical note

RESULTS

1. Diet Treatment Test

2. Factors Contributing to Call Rate

3. Factors Contributing to Time Spent Moving

4. Relationship Between Movement and Mating Interest

DISCUSSION

Declarations

STATEMENTS AND DECLARATIONS

FUNDING

Author Contribution

Acknowledgement

Data Availability

References

Additional Declarations

Supplementary Files

Status:

Version 1