DOI: 10.5061/dryad.zkh1893jv
title: Data from: Could adult or juvenile dispersal shape geographical parthenogenesis? Evidence from the facultatively parthenogenetic phasmid Megacrania batesii

description: Despite their individual reproductive flexibility, populations of many
 facultatively parthenogenetic animals vary in sex ratio and reproductive
 mode. Sex-specific dispersal could contribute to such spatial variation.
 We asked if sex-specific dispersal by adults or nymphs occurs in the
 facultatively parthenogenetic phasmid Megacrania batesii, which
 forms a geographical mosaic of mixed-sex (mostly sexually reproducing) and
 all-female (parthenogenetic) populations. If sex-specific
 dispersal contributes to sex-ratio variation in this species, we would
 expect to observe greater dispersal by females than by males. We
 carried out a mark-resighting field study over three years to investigate
 adult dispersal in mixed-sex and all-female populations. To better
 understand how males affect female behaviour, we also investigated pairing
 and mate-guarding. In addition, we investigated dispersal by hatchling
 nymphs in a semi-natural enclosure. Mean nightly movement distances did
 not differ between unpaired (single) females and males in the mixed-sex
 population. However, unpaired females moved further in mixed-sex than in
 all-female populations. Many adult females in the mixed-sex population
 continually carried guarding males on their dorsum. Pairs often remained
 together for multiple days, and few females or males were observed pairing
 with multiple partners. Paired females moved shorter distances than
 unpaired females, and such females’ movement increased following
 experimental removal of males. Hatchling nymphs rarely moved between
 plants. Our findings suggest that guarding males affect females’ movement
 patterns, but nymph and adult dispersal is unlikely to shape spatial
 variation in sex ratio in Megacrania batesii.
description: <em>Mark-resighting methodology</em>
 Within each population, we used a mark-resighting method to track
 movements of <em>Megacrania batesii </em>adults (and a few
 final-instar female nymphs). Individuals were marked on the first day of
 the study each year, and additional unmarked individuals were marked on
 subsequent days. Resighting data were collected either daily or every
 other day, starting on the 2<sup>nd</sup> or
 3<sup>rd</sup> day of the study. Newly sighted individuals
 were marked with unique codes on their thorax and/or wings. using black
 permanent marker (Artline xylene-free permanent marker, Shachihata, Japan)
 in situ on their host plants, without handling or restraining them. Host
 plants on which <em>Megacrania batesii </em>individuals were
 marked or resighted were tagged with numbered plastic tags. Both males and
 females can spray a defensive fluid when disturbed (Cermak and Hasenpusch
 2000; Jones and Bulbert 2020), which can complicate marking by depositing
 moisture on the thorax. If a spraying response occurred, we waited a few
 minutes and then attempted to write the same code on the forewings. When
 an individual was found at the base of a leaf, we gently tapped the tip of
 its abdomen to trigger it to crawl upwards to become accessible for
 marking. When marking male-female pairs, the male’s antennae sometimes
 blocked the female’s thorax. In such cases, the antennae were pushed to
 the side or the male was moved gently to the side or backwards to expose
 the female’s thorax. In 2020, we conducted a
 mark-resighting study from 2<sup>nd</sup> to
 14<sup>th</sup> February at CO and CB (only within the
 <em>Benstonea monticola</em> patch). At CO, we marked
 individuals on 2<sup>nd</sup> February, and then collected
 resighting data daily until 4<sup>th</sup> of February, and
 every second day thereafter until 14<sup>th </sup>of February.
 At population CB, we marked individuals on 3<sup>rd</sup>
 February, and then collected resighting data daily from
 4<sup>th</sup> February, and every second day thereafter until
 14<sup>th</sup> February. In addition to adult females, we
 also marked three final-instar female nymphs at CB. Almost no rain
 occurred during our mark-resighting study, and average maximum temperature
 was ~34.6ºC (Table S1-S3). In 2021, we conducted a mark-resighting study
 from 25<sup>th</sup> February to 8<sup>th</sup>
 March at CO and KB. At CO, we marked and resighted <em>Megacrania
 batesii </em>individuals in the same patch of <em>P.
 tectorius</em> plants as in 2020, as well as an adjacent patch (see
 Results). We marked individuals on 26<sup>th</sup> February,
 and then collected resighting data every other day until
 8<sup>th</sup> March. At KB, we marked individuals on
 26<sup>th </sup>February, and then collected resighting data
 every other day until 8<sup>th</sup> March. There was
 considerable rainfall during our mark-resighting study, and the average
 maximum temperature was ~30.5ºC (Table S1-S3). In 2022, we conducted a
 mark-resighting study from 22<sup>nd</sup> February to
 4<sup>th</sup> March at CO and CB (only within the
 <em>Pandanus tectorius</em> patch). At CO, we marked
 individuals in the same two patches as in 2021 on
 22<sup>nd</sup> February, and then collected resighting data
 every other day until 4<sup>th</sup> March. At CB, we marked
 individuals on 23<sup>rd</sup> February, and then collected
 resighting data every other day until 5<sup>th</sup> March.
 There was little rainfall during our field-study, and average maximum
 temperature was ~34.7 ºC (Table S1-S3). 
 <em>Dispersal</em> To estimate
 dispersal rates, we quantified how far individuals moved between
 successive sightings. We checked for previously marked individuals on each
 plant (absence or presence) on each resighting day, measured the distance
 between the previous sighting location and new location, and recorded the
 identity and pairing state (unpaired or paired) of each marked individual.
 We collected the Global Positioning System (GPS) coordinates of each
 individual at its point of initial sighting or resighting using a Garmin
 eTrex 20x GPS. Because GPS coordinates are imprecise over small distances,
 we also measured the linear distance between plants using a tape-measure
 and use these measurements in analyses of dispersal distance. The “nightly
 dispersal” distance was calculated for each individual each time it was
 resighted as the distance between the previous and current location
 divided by the number of nights between the current sighting and the
 previous sighting (since <em>Megacrania batesii </em>are
 mostly active at night). The mean nightly dispersal distance for each
 individual was calculated as the sum of the nightly dispersal distances
 divided by the number of nights between the initial sighting/marking and
 the final resighting. <em>Male removal
 experiment</em> To further investigate the effect
 of male guarding on female dispersal, we removed males from a patch of
 host plants at CO on the 3<sup>rd</sup> of March 2021,
 thoroughly checking both during the day and at night and removing any
 males that we could find. Locations of all females that had been separated
 from guarding males were recorded daily until the
 7<sup>th</sup> of March, and their nightly dispersals were
 measured. The removed males were kept in individual mesh cages in our
 field-laboratory, misted with water and provided fresh host plant leaves
 daily. The males were released in the same patch on
 7<sup>th</sup> of March.
 <em>Dispersal of hatchlings</em>
 We observed dispersal of <em>Megacrania batesii
 </em>hatchling nymphs from 25<sup>th</sup> July to
 28<sup>th</sup> August 2020 in a semi-natural enclosure set up
 inside a controlled-temperature room at UNSW Sydney. Hatchlings were
 obtained from eggs collected in the field between Cow Bay and Cape
 Tribulation, Queensland, in February 2020. Each day, newly hatched nymphs
 were sexed based on the morphology of the terminal abdominal sternites
 (see Miller et al. 2024a), marked individually with distinctive patterns
 of coloured dots using permanent marker (Sharpie, Australia), and released
 on <em>Pandanus tectorius</em> plants distributed on the floor
 of a controlled-temperature room (maintained at 25 ± 2°C and 60 ± 20%
 relative humidity; 12 hrs of cycle day/night with white and red lights).
 Six immature <em>Pandanus</em> plants (40 – 60 cm in height)
 were placed in the room, with one plant in each corner and two plants in
 the centre. Each morning, we recorded the locations of all hatchlings.
 Each nymph was monitored until it underwent its first molt, after which we
 were not able to track individuals because their individual markings were
 shed along with their exoskeletons. In total, we marked and released 55
 hatchlings (39 females, 16 males), and observed each hatchling over 10 ± 2
 days.
description: # Data from "Could adult or juvenile dispersal shape geographical
 parthenogenesis? Evidence from the facultatively parthenogenetic phasmid
 *Megacrania batesii*".
 [https://doi.org/10.5061/dryad.zkh1893jv](https://doi.org/10.5061/dryad.zkh1893jv) #### File: Individual\_summary\_publication.csv **Description:** Individual summary table while excluding male removal experiment  ##### Variables * year: The year (y) in which field study conducted. * pop_type: Whether the population is mixed-sex or all-female. * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * sex: The sex of the focal individual, represented as F for female and M for male. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. * Count: Total number of sightings for the focal individual including first observation. Individuals observed both paired and unpaired are listed twice, with the number of observations for each status shown in this column. Individuals observed both paired and unpaired are listed twice, with the number of observations for each status shown in this column. * Mean_disp_dist: Mean nightly dispersal distance for each individual. #### File: 7\_females\_no\_switching\_publication.csv **Description:** Male removal experiment  ##### Variables * year: The year (y) in which field study conducted. * date: Exact dates of annual visits to field sites. * days: The sequence of visits to each site is recorded, with each day labelled sequentially as day 1, day 2, and so forth. * time_interval: The time interval represents the number of nights between site checks. NA values are noted in this column for observation 1 and when an individual was not found. * observed_times: This variable indicates how many times the focal individual has been resighted after marking (e.g. obs3 indicates that the individual is sighted for the third time). If an individual is not found on a specific day, it is recorded as NA. * pop_type: Whether the population is mixed-sex or all-female. * location: Codes representing the three study sites (based on Miller et al. 2024 American Naturalist). * patch_type: Codes for host plant (Pandanus) patches at site CO. * sex: The sex of the focal individual, represented as F for female and M for male. * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of partner (guarding male or female being guarded). Individuals that are either found unpaired or not found at all on that observation day are recorded as NA. * status:The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. Individuals not found at all are recorded as NA. * plant_id: Unique ID for each host plant where a focal Megacrania batesii individual was found. If an individual is not found on a specific day, it is noted as NA. * dist_cm: The distance travelled (in cm) since the last observation each time (i.e., the distance between the previous and current host-plant where the individual was found). If an individual was not found on a specific day or was encountered for the first time, it is noted as NA. * nightly_dist:The nightly distance is calculated by dividing distance travelled by time interval (the number of nights between current and previous observation). If an individual was not found on a specific day or was encountered for the first time, it is noted as NA. * replacement: Indicates whether the individual is paired with the same individual as it was in previous observation or different individual. If an individual is missing on a specific day, it is noted as NA. * found_nf: Whether the individual is found or not found on each visit. * male_manipulation: Whether the observation is made while males were removed from patch B at CO in 2021 ("males removed") or not ("no male removal"). #### File: dispersal\_data\_all\_years\_publication.csv **Description:** Master data contains all three years of mark-resight studies  ##### Variables * year: The year (y) in which field study conducted. * date :Exact dates of annual visits to field sites. * days: The sequence of visits to each site, with each day labelled sequentially as day 1, day 2, and so forth. * time_interval: The time interval represents the number of nights between observations of the focal individual. NAs are present in this column for observation 1 because newly marked individuals were observed for the first time. * observed_times: This variable indicates how many times the focal individual has been resighted after marking (e.g. obs3 indicates that the individual is sighted for the third time). If an individual is not found on a specific day, it is recorded as NA. * pop_type: Whether the population is mixed-sex or all-female. * location: Codes representing the three study sites (based on Miller et al. 2024 American Naturalist). * patch_type: Codes for host plant (Pandanus) patches at site CO. All study sites have NA except for CO. * sex: The sex of the focal individual, represented as F for female and M for male. * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of partner (guarding male or female being guarded). Individuals that are either found unpaired or not found at all on that observation day are recorded as NA. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. Individuals not found at all are recorded as NA. * plant_id: Unique ID for the host plant where a Megacrania batesii focal individual was found. We did not keep track of individual plants across years, and therefore assigned a new ID to each host plant each year. If an individual was not found on a specific day, the plant ID is noted as NA. * dist_cm: The distance travelled (in cm) since the last observation each time (i.e., the distance between the previous and current host-plant where the individual was found). If an individual was not found on a specific day or was encountered for the first time, it is noted as NA. * nightly_dist: The nightly distance is calculated by dividing distance travelled by time interval (the number of nights between current and previous observation). If an individual was not found on a specific day or was encountered for the first time, it is noted as NA. * replacement: Indicates whether the individual is paired with the same individual as it was in previous observation or different individual. If an individual is missing on a specific day, it is noted as NA. * found_nf: Whether the individual is found or not found on each visit. Last day of observation of 2021, when males were reintroduced to the patch B is NA. This is because resightings of these males were not included in the analyses. * male_manipulation: Whether the observation is made while males were removed from patch B at CO in 2021 ("males removed") or not ("no male removal"). * exclude: Used to exclude rows with paired males in the ind_id column to avoid duplicates. Paired males are listed as partners in the "paired_with" column. #### File: all\_combined\_7females\_updated.csv **Description:** Supplementary Figure S3 ##### Variables * date: Exact dates of annual visits to field sites. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. * sex: The sex of the focal individual, represented as F * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of females whether they paired or unpaired. Any NAs represent females whose males were removed. * patch: Codes for host plant (Pandanus) patches at site CO. B represents Middle patch CO in 2021 * plant_id: Unique ID for the host plant where a Megacrania batesii focal individual was found. * lat: GPS coordinates of plants (Latitude). * long: GPS coordinates of plants (Longitude). * division :Connecting points to a line. Any NAs represent females that did not move and remained on the host plant. * order: Points are connected based on order of points. Any NAs represent females that did not move and remained on the host plant. * male_removal: Females status while paired represents "before", and while unpaired represents "after". #### File: non\_removal\_patch\_all\_publication.csv **Description:** Part of male removal experiment.  ##### Variables * year: The year (2021) in which field study conducted. * date : Exact dates of annual visits to field sites. * days: The sequence of visits to each site, with each day labelled sequentially as day 1, day 2, and so forth. * time_interval: The time interval represents the number of nights between observations of the focal individual. NAs are present in this column for observation 1 because newly marked individuals were observed for the first time. * observed_times: This variable indicates how many times the focal individual has been resighted after marking (e.g. obs3 indicates that the individual is sighted for the third time). If an individual is not found on a specific day, it is recorded as NA. * pop_type: Whether the population is mixed-sex or all-female. * location: Codes representing the three study sites (based on Miller et al. 2024 American Naturalist). * patch_type: Codes for host plant (Pandanus) patches at site CO. * sex: The sex of the focal individual, represented as F for female. * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of partner (guarding male or female being guarded). Individuals that are either found unpaired or not found at all on that observation day are recorded as NA. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. Individuals not found at all are recorded as NA. * plant_id: Unique ID for the host plant where a Megacrania batesii focal individual was found. We did not keep track of individual plants across years, and therefore assigned a new ID to each host plant each year. If an individual was not found on a specific day, the plant ID is noted as NA. * dist_cm: The distance travelled (in cm) since the last observation each time (i.e., the distance between the previous and current host-plant where the individual was found). If an individual was not found on a specific day or was encountered for the first time, it is noted as NA. * nightly_dist: The nightly distance is calculated by dividing distance travelled by time interval (the number of nights between current and previous observation). If an individual was not found on a specific day or was encountered for the first time, it is noted as NA. * replacement: Indicates whether the individual is paired with the same individual as it was in previous observation or different individual. If an individual is missing on a specific day or found unpaired, it is noted as NA. * found_nf: Whether the individual is found or not found on each visit. * male_manipulation: Patches where male removal did not occur. * male_removal: Paired females in Southern and Northern patches before and including March 3, 2021 (when males were removed from the Middle patch) with nightly dispersal distances of those females after this date. #### File: all\_combined\_2020\_CO.csv **Description:** Supplementary Figure S1 ##### Variables * date : Exact dates of annual visits to field sites. * sex: The sex of the focal individual, represented as F for female and M for male. * Individual code: The unique individual ID of each focal individual (i.e., each individual that was marked). * Paired with : Individuals that are found unpaired on that observation day are recorded as NA. * single/pairs: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. * Plant id : Unique ID for the host plant where a Megacrania batesii focal individual was found. * lat: GPS coordinates of plants (Latitude). * lon: GPS coordinates of plants (Longitude). * DIVISION : Connecting points to a line. Any Nas represent females that did not move and remained on the host plant. * ORDER: Connecting points to a line. Any Nas represent females that did not move and remained on the host plant. #### File: all\_combined\_patch\_a\_c.csv **Description:** Supplementary Figure S2 ##### Variables * date: Exact dates of annual visits to field sites. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. * sex: The sex of the focal individual, represented as F for female and M for male. * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of partner (guarding male or female being guarded). Individuals that are found unpaired on that observation day are recorded as NA. * patch: Codes for host plant (Pandanus) patches at site CO. A represents Southern patch while C represents Northern patch. * plant_id: Unique ID for the host plant where a Megacrania batesii focal individual was found. * lat: GPS coordinates of plants (Latitude). * long: GPS coordinates of plants (Longitude). * division : Connecting points to a line. * order: Points are connected based on order of points. #### File: all\_combined\_co\_2022.csv **Description:** Supplementary Figure S5 ##### Variables * date : Exact dates of annual visits to field sites. * patch_type: Codes for host plant (Pandanus) patches at site CO. A represents Southern patch and B represents Middle patch CO in 2021 * sex: The sex of the focal individual, represented as F for female and M for male. * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of partner (guarding male or female being guarded). Individuals that are found unpaired on that observation day are recorded as NA. * plant_id: Unique ID for the host plant where a Megacrania batesii focal individual was found. * lat: GPS coordinates of plants (Latitude). * long: GPS coordinates of plants (Longitude). * division : Connecting points to a line. * order: Points are connected based on order of points. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. #### File: all\_combined\_patch\_b\_excluding\_7females.csv **Description:** Supplementary Figure S4 ##### Variables * date: Exact dates of annual visits to field sites. * sex: The sex of the focal individual, represented as F * ind_id: The unique individual ID of each focal individual (i.e., each individual that was marked). * paired_with: The individual ID of partner (guarding male or female being guarded). Individuals that are found unpaired on that observation day are recorded as NA. * patch: Codes for host plant (Pandanus) patches at site CO. B represents Middle patch in 2021. C represents Northern patch. * plant_id: Unique ID for the host plant where a Megacrania batesii focal individual was found. * lat: GPS coordinates of plants (Latitude). * long: GPS coordinates of plants (Longitude). * division : Connecting points to a line. * order: Points are connected based on order of points. * status: The pairing status, whether the individual is found 'paired' or 'unpaired' on each visit. ## ## Access information Other publicly accessible locations of the data: * NA.  Data was derived from the following sources: * NA.