DOI: 10.5061/dryad.0zpc8672b
title: Wolbachia-infected pharaoh ant colonies have higher egg production, metabolic rate, and worker survival

description: Wolbachia is a widespread endosymbiotic bacteria with diverse phenotypic
 effects on its insect hosts, ranging from parasitic to mutualistic.
 Wolbachia also commonly infects social insects, where it faces unique
 challenges associated with its hosts’ caste-based reproductive division of
 labor and colony living. Here we dissect the benefits and costs of
 Wolbachia infection on life-history traits of the invasive pharaoh ant,
 Monomorium pharaonis. Pharaoh ants are relatively short-lived and show
 natural variation in Wolbachia infection between colonies, thereby making
 them an ideal model system for this study. We quantified effects on the
 lifespan of queen and worker castes, the egg-laying rate of queens across
 queen lifespan, and the metabolic rates of whole colonies and colony
 members. Newly-infected queens laid more eggs than uninfected queens but
 had similar metabolic rates and lifespans. Surprisingly, infected workers
 outlived uninfected workers. At the colony level, infected colonies were
 more productive due to increased queen egg-laying rates and worker
 longevity, and infected colonies had higher metabolic rates during peak
 colony productivity. While some effects of infection, such as elevated
 colony-level metabolic rates may be detrimental in more stressful natural
 conditions, we did not find any costs of infection under relatively benign
 laboratory conditions. Overall, our study emphasizes the beneficial
 effects of Wolbachia on colony-level growth and metabolism in this
 species.
description: ## *Wolbachia*-infected pharaoh ant colonies have higher egg production,
 metabolic rate, and worker survival ### Reference Information This is the
 README file for the dataset associated with the paper
 "*Wolbachia*-infected pharaoh ant colonies have higher egg
 production, metabolic rate, and worker survival". This file uses
 Markdown syntax and has a .md extension *** ### General details of this
 README * **File name:** README(.md) * **Author(s):** Sachin Suresh *
 **Contributors(s):** Timothy A Linksvayer * **Date created:** 01/30/2023
 (mm/dd/yyyy) * **Date modified:** 09/10/2023 (mm/dd/yyyy) *** ### Dataset
 Version and Release History * **Version number:** 2.0.0 * **Date:**
 09/10/2023 (mm/dd/yyyy) * **Identifier:** DOI: 10.5061/dryad.0zpc8672b ***
 ### Dataset Attribution and Usage * **Dataset Title:** Data for the
 manuscript '*Wolbachia*-infected pharaoh ant colonies have higher egg
 production, metabolic rate, and worker survival' * **Dataset
 collection and contribution:** Rohini Singh * **License:** CC0 1.0
 Universal (CC0 1.0) * **Dataset usage:** The authors sincerely request the
 researchers to reach out for re-using this dataset
 (https://creativecommons.org/publicdomain/zero/1.0/) * **Dataset
 citation:** &gt; Rohini Singh, Sachin Suresh, Jennifer H. Fewell, Jon
 F. Harrison, Timothy A. Linksvayer. 2023. Data for the article
 '*Wolbachia*-infected pharaoh ant colonies have higher egg
 production, metabolic rate, and worker survival',
 https://doi.org/10.5061/dryad.0zpc8672b *** ### Contact Information *
 Name: Dr. Timothy A. Linksvayer (corresponding author) * Affiliations:
 Arizona State University; School of Life Sciences * Email:
 tlinksvayer@gmail.com * Alternate Email: tlinksva@asu.edu #### Alternative
 Contact * Name: Sachin Suresh (Ph.D. student) * Affiliations: Arizona
 State University; School of Life Sciences * ORCID ID:
 https://orcid.org/0000-0002-5245-7008 * Email: ssures53@asu.edu *
 Alternate Email: sachinddr3@gmail.com *** ### Funding This work was funded
 by the National Science Foundation (IOS-1452520) awarded to Timothy A.
 Linksvayer. *** ### Acknowledgments We are grateful to Dr. Juergen Liebig
 for letting us safely house the ants at Arizona State University, Xuaohui
 Guo in the Fewell lab and Trevor Fox in the Harrison lab at the Arizona
 State University for assisting with metabolic rate measurement *** ## Data
 and File Overview ### Summary Metrics * **File count:** 12 * **Total file
 size:** 270 KB * **File formats:** .csv, .R ### Table of Contents *
 2019-fec-new-queens.csv * met-rate-vid-activity.csv * mr-brood.csv *
 mr-colony.csv * mr-queens.csv * queen2020-survival.csv *
 work-surv2019-long.csv * qn\_fc.R * met\_rate.R * met-rate-queens.R *
 survival-assay.R * fec\_qn\_sachin\_sml.R *** ### Software **Recommended
 software/tools:** RStudio 2022.12.0; R version 4.2.2 *** ## File Details
 ### a) 2019-fec-new-queens.csv * **Description:** a comma-delimited file
 containing queen egg-laying data along with other colony attributes. This
 file is associated with the experiment which compares the egg-laying rates
 of queens in wolbachia-infected and -uninfected colonies. * **Format(s):**
 .csv * **Size:** 18.1 KB * **Dimensions:** 372 rows x 13 columns *
 **Variables:** * **date:** Date at which the data was collected *
 **wolbachia:** Refers to *wolbachia* infection status. * **day:** Number
 of days since the start of experimental protocol * **colonyID:** Unique
 identifier for the colonies * **q.age.days:** Age of queen(s) in days *
 **males:** Number of males in the colony * **workers:** Number of workers
 in the colony * **queens:** Number of queens in the colony * **eggs:**
 Number of eggs laid by the queens * **yl:** Number of young larvae *
 **ol:** Number of old larvae * **worker.pp:** Number of worker pre-pupae *
 **worker.pup:** Number of worker pupae ### b) met-rate-vid-activity.csv *
 **Description:** a comma-delimited file containing colony-activity data
 along with other colony attributes. This file is associated with the
 experiment which compares the metabolic rates of wolbachia-infected and
 -uninfected colonies. * **Format(s):** .csv * **Size:** 1.88 KB *
 **Dimensions:** 42 rows x 6 columns * **Variables:** * **year:**
 Respective year at which the data was collected * **colony:** Unique
 identifier for the colonies * **wolbachia:** Refers to *wolbachia*
 infection status. * **total.frames:** Total number of frames in the video
 analyzed for a colony * **avg.chg.pxl:** Average of the change in pixel
 value * **sd.chg.pxl:** Standard deviation of the change in pixel value
 ### c) mr-brood.csv * **Description:** a comma-delimited file containing
 metabolic rate for brood along with other colony attributes. This file is
 associated with the experiment which compares the metabolic rates of brood
 in wolbachia-infected and -uninfected conditions. * **Format(s):** .csv *
 **Size:** 5.52 KB * **Dimensions:** 23 rows x 30 columns * **Variables:**
 * **mr.date:** Date at which the data was collected * **colony:** Unique
 identifier for the colonies * **wolbachia:** Refers to *wolbachia*
 infection status. * **resp.chamber:** Type of respiratory chamber used *
 **queen.age:** Age of queen(s) in days * **eggs:** Number of eggs *
 **young.larvae:** Number of young larvae * **old.larvae:** Number of old
 larvae * **worker.pupae:** Number of worker pupae * **air.flow:** Rate of
 air flow (mL/min) * **rq:** respiratory quotient (ratio of carbon dioxide
 produced to oxygen consumed) (dimensionless number) * **mass.before:**
 Mass before the experiment (grams) * **mass.after:** Mass after the
 experiment (grams) * **measure:** Time taken for measurement of CO2
 emission (seconds) * **measure.time:** Time taken for measurement of CO2
 emission (minutes) * **co2.mean:** Mean CO2 emission from brood (ppm) *
 **co2. sd:** Standard deviation of the CO2 emission from brood (ppm) *
 **temp.mean:** Mean temperature of the brood setup (Degree celsius) *
 **temp. sd:** Standard deviation of the temperature of the brood setup
 (Degree celsius) * **humid.mean:** Mean humidity of the brood setup (ppm)
 * **humid. sd:** Standard deviation of the brood humidity (ppm) *
 **comments:** Comments regarding the experimental conditions *
 **trash.measure.sec:** Measurement of CO2 emission in trash in seconds *
 **trash.measure.min:** Measurement of CO2 emission in trash in minutes *
 **trash.co2.mean:** Mean CO2 emission from trash (ppm) * **trash.co2.
 sd:** Standard deviation of the CO2 emissions from trash (ppm) *
 **trash.temp.mean:** Mean temperature of the trash (Degree celsius) *
 **trash.temp. sd:** Standard deviation of the trash (Degree celsius) *
 **trash.humid.mean:** Mean humidity of the trash (ppm) * **trash.humid.
 sd:** Standard deviation of the trash humidity (ppm) ### d) mr-colony.csv
 * **Description:** a comma-delimited file containing metabolic rate for
 the whole colony along with other attributes. This file is associated with
 the experiment which compares the metabolic rates of whole-colonies in
 wolbachia-infected and -uninfected conditions. * **Format(s):** .csv *
 **Size:** 13.4 KB * **Dimensions:** 51 rows x 38 columns * **Variables:**
 * **year:** Respective year at which the data was collected * **mr.date:**
 Date at which the data was collected * **colony:** Unique identifier for
 the colonies * **wolbachia:** Refers to *wolbachia* infection status. *
 **resp.chamber:** Type of respiratory chamber used *
 **lighting.during.recording:** Whether lighting was used during recording
 * **humidity:** Refers to whether water tube is present/absent
 respirometer during measurement (yes/no) * **nest.shape:** Type of nest
 chamber used * **queen.age:** Age of queen(s) in days * **eggs:** Number
 of eggs * **young.larvae:** Number of young larvae * **old.larvae:**
 Number of old larvae * **worker.pupae:** Number of worker pupae *
 **queens:** Number of queens * **queens:** Number of workers *
 **air.flow:** Rate of air flow (mL/min) * **rq:** respiratory quotient
 (ratio of carbon dioxide produced to oxygen consumed)(dimensionless
 number) * **brood.prp:** Proportion of brood per colony * **mass.before:**
 Mass before the experiment (grams) * **mass.after:** Mass after the
 experiment (grams) * **measure:** Time taken for measurement of CO2
 emission (seconds) * **measure.time:** Time taken for measurement of CO2
 emission (minutes) * **co2.mean:** Mean CO2 emission from colony (ppm) *
 **co2. sd:** Standard deviation of the CO2 emission from colony (ppm) *
 **temp.mean:** Mean temperature of the colony (Degree celsius) * **temp.
 sd:** Standard deviation of the colony temperature (Degree celsius) *
 **humid.mean:** Mean humidity of the colony (ppm) * **humid. sd:**
 Standard deviation of the colony humidity (ppm) * **trash.measure.sec:**
 Measurement of CO2 emission in trash in seconds * **trash.measure.min:**
 Measurement of CO2 emission in trash in minutes * **trash.co2.mean:** Mean
 CO2 emission from trash (ppm) * **trash.co2. sd:** Standard deviation of
 the CO2 emissions from trash (ppm) * **trash.temp.mean:** Mean temperature
 of the trash (Degree celsius) * **trash.temp. sd:** Standard deviation of
 the trash (Degree celsius) * **trash.humid.mean:** Mean humidity of the
 trash (ppm) * **trash.humid. sd:** Standard deviation of the trash
 humidity (ppm) * **video-activity:** Date of the recorded video activity
 ### e) mr-queens.csv * **Description:** a comma-delimited file containing
 metabolic rate for just the queens along with other attributes. This file
 is associated with the experiment which compares the metabolic rates of
 queens in wolbachia-infected and -uninfected conditions. * **Format(s):**
 .csv * **Size:** 5.36 KB * **Dimensions:** 29 rows x 20 columns *
 **Variables:** * **Date:** Date at which the data was collected *
 **queens. id:** Unique identifier for the queens * **wolbachia:** Refers
 to *wolbachia* infection status. * **first.baseline:** Time at which first
 baseline measurment was taken * **start.settle:** Time at which queens
 settled down * **end.measure:** End time of measurement *
 **flow.duration.min:** Flow duration in minutes * **flow.duration. hr:**
 Flow duration in hours * **last.baseline:** Time at which last baseline
 measurment was taken * **queens:** Number of queens * **air.flow:** Rate
 of air flow (mL/min) * **rq:** respiratory quotient (ratio of carbon
 dioxide produced to oxygen consumed) (dimensionless number) * **mass:**
 Mass of the queens (grams) * **queen.age:** Age of the queen in days *
 **temp:** Temperature of the setup (Degree celsius) * **measure:** Time
 taken for measurement of CO2 emission in seconds * **measure.time:** Time
 taken for measurement of CO2 emission in minutes * **co2.mean:** Mean CO2
 emission from queens (ppm) * **co2. sd:** Standard deviation of the CO2
 emission from queens (ppm) * **comments:** Comments regarding the
 experimental conditions ### f) queen2020-survival.csv * **Description:** a
 comma-delimited file containing queen survival data along with other
 colony attributes. This file is associated with the experiment which
 compares the survival of queens in wolbachia-infected and -uninfected
 colonies. * **Format(s):** .csv * **Size:** 36.2 KB * **Dimensions:** 612
 rows x 15 columns * **Variables:** * **date:** Date at which the data was
 collected * **colony:** Unique identifier for the colonies *
 **wolbachia:** Refers to *wolbachia* infection status. * **week:** Week
 since the start of the observation * **day:** Number of days since the
 start of experimental protocol * **queen.age:** Age of queen(s) in days *
 **queens:** Number of queens in the colony * **worker:** Number of workers
 in the colony * **eggs:** Number of eggs laid by the queens *
 **young.larvae:** Number of young larvae * **old.larvae:** Number of old
 larvae * **worker.pre.pup:** Number of worker pre-pupae * **worker.pup:**
 Number of worker pupae * **queen.pup:** Number of queen pupae *
 **male.pup:** Number of male pupae * **comments:** Miscellaneous comments
 ### g) work-surv2019-long.csv * **Description:** a comma-delimited file
 containing worker survival data along with other colony attributes. This
 file is associated with the experiment which compares the survival of
 workers in wolbachia-infected and -uninfected colonies. * **Format(s):**
 .csv * **Size:** 35.6 KB * **Dimensions:** 1296 rows x 7 columns *
 **Variables:** * **groupID:** Identifier for the group * **day:** Number
 of days since the start of experimental protocol * **worker.age:** Age of
 worker(s) in days * **colony.source:** Identifier of the source colony *
 **sub.colony:** Sub colony identifier * **wolbachia:** Refers to
 *wolbachia* infection status. * **worker:** Number of workers ### h)
 qn\_fc.R * **Description:** an R script for visualization and analysis of
 queen egg-laying data. This file is associated with the experiment which
 compares the egg-laying rates of queens in wolbachia-infected and
 -uninfected colonies. All the commands and codes inside the script are
 annotated. * **Format(s):** .R * **Size:** 25.3 KB ### i) met\_rate.R *
 **Description:** an R script for visualization and analysis of metabolic
 rate data. This file is associated with the experiment which compares the
 metabolic rates of whole-colonies, workers and brood in wolbachia-infected
 and -uninfected conditions. All the commands and codes inside the script
 are annotated. * **Format(s):** .R * **Size:** 45.5 KB ### j)
 met-rate-queens.R * **Description:** an R script for visualization and
 analysis of queen metabolic rate data. This file is associated with the
 experiment which compares the metabolic rates of queens in
 wolbachia-infected and -uninfected conditions. All the commands and codes
 inside the script are annotated. * **Format(s):** .R * **Size:** 9.82 KB
 ### k) survival-assay.R * **Description:** an R script for visualization
 and analysis of queen and worker survival data. This file is associated
 with the experiment which compares the survival of queens and workers in
 wolbachia-infected and -uninfected colonies. All the commands and codes
 inside the script are annotated. * **Format(s):** .R * **Size:** 60.6 KB
 ### **l) fec\_qn\_sachin\_sml.R** * **Description:** an R script for
 visualization and analysis of queen egg-laying data. This file is
 associated with the experiment which compares the egg-laying rates of
 queens in wolbachia-infected and -uninfected colonies. All the commands
 and codes inside the script are annotated. Also, note that this script is
 a trimmed version of the R-script 'fec\_qn.r' to streamline the
 analysis and plots * **Format(s):** .R * **Size:** 13 KB *** ## Experiment
 Details A brief summary of the experiments and results performed in the
 paper is mentioned below. The data files and scripts associated with the
 individual studies are also mentioned. ### a) Egg laying by queens
 **Experiment 1a:** Comparison of egg-laying difference between newly-mated
 infected and uninfected queens over 50 days. **Result:** Newly-mated
 *Wolbachia*-infected queens produced more eggs over time than uninfected
 queens (GLMER: 2 = 7.6, p = 0.005; Fig 1a, main text). * **Raw data:**
 2019-fec-new-queens.csv * **R script:** qn\_fc.R **Experiment 1b:**
 Comparison of egg-laying differences between 20 *Wolbachia*-infected and
 uninfected queens when the queens were one, three, four, six, and nine
 months old to quantify differences across the queens' lifespan.
 \*\*Result: \*\**Wolbachia*-infected colonies have higher metabolic rates
 depending on the stage of the colony life cycle. * **Raw data:**
 2019-fec-new-queens.csv * **R script:** qn\_fc.R, fec\_qn\_sachin\_sml.R
 ### b) Metabolic Rates of whole colonies, queens, and brood **Experiment 2
 :** We compared metabolic rates of (a) infected versus uninfected whole
 colonies at two different colony life stages: colonies with one-month-old
 queens and three-month-old queens and (b) different colony members, namely
 the brood and the queens from colonies with one-month-old queens.
 **Results:** Metabolic rates differ between infected and uninfected
 whole-colonies but are dependent on colony life cycle stage and colony
 component. Metabolic rates did not differ between other infected and
 uninfected groups early in the colony life cycle (fig 2 and fig s4 in main
 text). * **Raw data:** met-rate-vid-activity.csv, mr-brood.csv,
 mr-colony.csv, mr-queens.csv * **R scripts:** met\_rate.R,
 met-rate-queens.R ### c) Survival of queens and workers **Experiment 3 :**
 We estimated the effect of Wolbachia infection status on worker survival.
 **Results:** Wolbachia-infected and uninfected queens had similar group-
 (Log-rank test, p = 0.8; Fig. 3a in main text) and individual-level
 survival rates (GLMM, 2 = 0.2, p &lt;0.05; Fig. 3b in main text).
 Infected workers had higher group-level survival (Log-rank test, p = 0.02;
 Fig 3c) and individual-level survival (GLMM, 2 = 12, p &lt; 0.001;
 Fig. 3d in) than uninfected workers (Fig. 3c,d). * **Raw data:**
 queen2020-survival.csv, work-surv2019-long.csv * **R script:**
 survival-assay.R *** End of README ***