DOI: 10.5061/dryad.m63xsj49w
title: Social organization of necrophoresis: Insights into disease risk management in ant societies

description: Insect societies, which are at a high risk of disease outbreaks, have
 evolved sanitary strategies that contribute to their social immunity.
 Here, we investigated in the red ant Myrmica rubra, how the discarding of
 nestmate cadavers is socially organized depending on the associated
 pathogenicity. We examined whether necrophoresis is carried out by a
 specific functional group of workers or by any nestmates that may become
 short-term specialists. By observing the behavioural profiles of tagged
 individuals, we assigned half of the colony members to functional groups
 (foragers, intermittent-foragers, domestics, nurses and inactives).
 Following the introduction of uninfected or sporulating corpses into the
 nest, intermittent-foragers were the functional group most involved in
 necrophoresis, as they touched, moved, and discarded more cadavers.
 Interestingly, sporulating corpses induced a more generalized response in
 workers from all functional groups, thereby accelerating their rejection
 from the nest. The individuals contacting corpses were also
 prophylactically engaged in more grooming behaviour, suggesting the
 existence of hygienist workers within ant colonies. These findings raise
 questions about a trade-off existing between concentrating health risks on
 a few workers who are highly specialized in necrophoresis and exposing a
 larger population of nestmates who cooperate to speed up nest
 sanitisation.
description: <em>2.1   </em><em>Biological
 models</em> The ant species, <em>Myrmica
 rubra</em> is commonly used as a biological model in studies about
 social immunity [16,17, 40]. <em>Myrmica rubra</em> is a
 common ant species in temperate areas of Europe and is considered an
 invasive ant in North America. This polygynous species usually lives in
 semi-open forests and grasslands [41], with nest populations ranging from
 1 to 20 queens and 100 to 2500 workers in Europe [42]. Its nests are dug
 in various substrates, such as soil under stones, rotting wood, or roots
 of nettles and bramble bushes ([42], personal observations). Although ants
 share confined nest sites with genetically related nestmates, disease
 outbreaks leading to the death of the whole colony are rarely observed
 [43]. However, as an omnivorous species that frequently forages on prey,
 M. rubra workers are exposed to insect remains, which can be a source of
 entomopathogens. The ant genus <em>Myrmica</em> is actually
 exposed to a wide variety of parasites [44] and is commonly confronted
 <em>in naturae</em> to the generalist entomopathogenic fungus
 <em>Beauveria bassiana</em> [44,45]. Infection by this fungal
 pathogen starts with the attachment of conidia, i.e. asexual propagules,
 on their cuticle, and by the release of an enzymatic cocktail allowing a
 germ tube to penetrate the cuticle and enter the insect’s body [46]. The
 fungal mycelium then grows and invades the hemocoel, leading to the death
 of the host [47]. Ultimately, the fungus works its way outside the insect
 body to produce sporulating structures bearing conidia propagules [46]. At
 the last stage of infection, conidia are produced over the host cadaver,
 resulting in the white fluffy appearance of <em>B.bassiana
 </em>sporulating corpses, also called ‘white muscardine’
 [46]. <em>2.2   </em><em>Collection
 and rearing of ant colonies</em> Five
 <em>M. rubra</em> colonies were collected during the summer of
 2021 in woods located at Aiseau-Presles (Province of Hainaut: N
 50°25.657’; E 04°35.674’) and Sambreville (Province of Namur: N
 50°25.210’; E 04°37.878’). Nests were dug out from the litter and birch
 wood logs. Ant colonies were maintained in a room with constant
 temperature and humidity (21 ± 1C° and 50 ± 5%), and 12h :12h. Dark:Light
 regime and darkened test tubes were offered as nesting sites.
 From these colonies, we made five experimental colonies
 consisting of two queens, around 225 workers (1/3 foragers and 2/3
 internal workers), and 60 larvae at the second and third instars. Each
 experimental colony was derived from a different mother colony. Foragers
 were sampled from among ants walking outside the nests, and internal
 workers were removed from nesting test tubes. These ants were transferred
 to an experimental tray (30 cm × 22 cm × 7.5 cm), the bottom of which was
 covered by a 1 cm plaster layer, and the edges were coated with
 Fluon<sup>TM</sup> to prevent ants from escaping. A hole was
 drilled in the tray, vertical to the experimental nest. A cotton wick was
 inserted into the hole and placed over a sponge soaked daily to evenly
 moisten the plaster below the nest. The experimental
 nest was circular (3.45 cm radius) with a single chamber and a single
 entrance (5 × 5 × 2 mm). It was made of two square Plexiglas plates (8 cm
 on each side and 2 mm in thickness). The gap between these two plates
 created a 2 mm-high space between which ants settled in a monolayer, thus
 facilitating behavioural observations (Fig. 1). The nests were designed in
 vector drawings using the InkScape software and cut out using a laser
 cutter (HIGH-Z S-1000/T CNC ROUTER). The nest roof plate had a central
 circular hole (1.1 cm diameter) that could be alternately closed by one of
 the following two removable parts. The first removable part (red in Fig.
 1.a) was a column passing through the roof down to the plaster ground (1.1
 cm radius * 4.1 mm high). This created a space in the centre of the nest
 where workers could not settle and where corpses could be further dropped
 inside the nest with minimal disturbance to nestmates (see experimental
 procedure). The second removable part (blue in Fig. 1.d) was a transparent
 circular plug that served as a roof cover during the four hours of
 observations following the insertion of corpses. This plug allowed for the
 passage of ants underneath and provided them with access to the inserted
 items. Finally, the nest was surrounded by a plexiglass cage coated with
 Fluon<sup>TM</sup> (polytetrafluoroethylene) to prevent the
 ants from climbing above the nest and disturbing behavioural observations.
 Experimental colonies were provided with water, a 0.3M sucrose solution
 and ten dead fruit flies (<em>Drosophila melanogaster)</em>
 were placed daily in the area at 9:30 am. Fruit flies were chosen as the
 protein source because they were small enough to be retrieved by ants
 through the nest entrance and large enough to observe prey consumption by
 ants inside the nest. <em>2.3  
 </em><em>Experimental procedure</em>
 <em>2.3.1       
 </em><em>Planning</em> The experiment
 lasted for three weeks for each tested colony (Fig. 2). It began with two
 days of tagging, followed by two days of settlement and habituation of the
 ants to the experimental setup. It was organised into three distinct
 experimental sessions. During the first session, the behaviour of tagged
 ant individuals inside the nest was quantified for three days to further
 assign them to a functional group. The second session consisted of
 introducing uninfected corpses and, two days later, sporulating dead
 nestmates. This allowed us to quantify the dynamics of corpse removal.
 Particular attention was paid to the interaction of each tagged ant with
 corpses to assess whether their contribution to necrophoresis differed
 according to their functional group. During the third session, we
 monitored daily mortality and the causes of death of workers by placing
 their cadavers under sporulation conditions. This monitoring started on
 day 5, at the same time as session 1, and continued until day 21 (Fig.
 2). <em>2.3.2       
 </em><em>Tagging</em> Half of the
 worker population in each experimental colony was tagged individually. The
 tags were made of waterproof "toughprint" paper (0.9
 mm<sup>2</sup> square) marked with four tiny 0.45 mm * 0.45 mm
 coloured squares. One square was black and the other three had a
 combination of different colours, selected to maximise contrast on video
 recordings (blue, green, red, white, and yellow, Fig. 1). This allowed us
 to identify the ant individual, regardless of its position, simply reading
 the colours clockwise, starting with the black square.
 Before being tagged, the ants were briefly CO2-anaesthesized for
 45 seconds. To restrict their movements, the ant head and thorax were
 delicately placed in slits made of a professional make-up sponge
 (Cala<sup>TM</sup>). A droplet of glue droplet
 (Loctite<sup>TM</sup> superglue) was applied to the first
 abdominal segment using a small guitar string
 (D'Addario<sup>TM</sup> NYS007), and the coloured tag was
 placed using a toothpick (See SI). While being removed from the slit, the
 tagged ants were briefly anesthetized again for one minute and then
 isolated in Petri dishes until the glue dried completely. Four hours
 later, the tagged ants were placed in the experimental tray along with
 their conspecifics. As approximately 20% of the tagging attempts failed,
 we tagged 125 workers to ensure that we had approximately 100 tagged
 workers per colony at the beginning of the experiment (see SI for more
 details). The ants were randomly selected for tagging in a ratio of
 two-thirds internal to one-third external workers. We excluded callows or
 any individual showing signs of injury. In total, 491 workers were tagged
 successfully. As shown in previous studies, tagging had no significant
 effect on a worker's behaviour [48-50], except for a temporary
 increase in self-grooming behaviours that lasted no longer than 24
 hours. <em>2.3.3       
 </em><em>Session 1: Behavioural profile and assignment to a
 functional group</em> For each tagged individual,
 we quantified its location (outside VS inside the nest) as well as its
 behaviours inside the nest by observing it three times (10:30, 13:30, and
 16:30) for 3 min over three successive days (Fig. 1). The recorded
 behaviours are listed in Table 1. On video recordings, we quantified the
 proportion of time each tagged ant was engaged in a given behaviour over
 the total duration during which this ant was observed inside the nest. The
 time that a tagged worker spent outside the nest was considered as
 foraging. Inside the nest, if a behaviour stopped for less than five
 seconds, it was considered uninterrupted. If an ant was motionless and did
 not engage in any activity for at least five seconds, it was recorded as
 inactive (based on the same criteria as in [51] study). Any instance of
 grooming behaviour performed by a worker alone, cleaning any part of its
 body such as antennae or abdominal tip, was classified as ‘self-grooming’.
 Similarly, when a worker actively groomed a nestmate, it was reported as
 ‘allo-grooming’. Once the data were collected, we compiled a behavioural
 profile for each tagged worker. These proportion of time spent on each
 task were used in a cluster analysis to assign each worker to one of the
 functional groups (see the Statistical Analysis section for further
 details). <em>2.3.4 Session 2: Necrophoresis
 </em> We compared the behaviour of tagged
 individuals exposed to either 10 uninfected or 10 sporulating corpses. The
 10 uninfected cadavers were nestmates killed by freezing one day before
 their corpses were introduced into the nest (Fig. 1). Indeed, it takes 24
 hours for the cuticular profile of dead workers to become enriched in
 oleic and linoleic acids, which allows their recognition as cadavers and
 triggers necrophoresis [52,53]. The ten sporulating cadavers were
 nestmates that died from infection by the entomopathogenic fungus
 <em>B.bassiana </em>(Naturalis-L<sup>TM</sup>).
 These sporulating corpses were produced prior to the start of the
 experiment. To do so, we topically applied a droplet of
 Naturalis-L<sup>TM</sup> insecticide (± 4<em>
 µL</em>) to the abdomen of 30 nestmates that were isolated in a
 Petri dish with a wet cotton ball until their death. On the day of their
 death, ant cadavers were washed with ethanol and distilled water according
 to Lacey's method [54] to avoid contamination by microorganisms other
 than <em>B.bassiana </em>fungus. Following this treatment, the
 cadavers were placed on moist filter paper in a Petri dish sealed with
 parafilm and placed in a temperature-controlled cabinet at 25°C until the
 fungus sporulated over the ant body. As for the course
 of the necrophoresis experiment, ten uninfected cadavers were introduced
 on day 8 in the centre of the experimental nest (Fig. 1). After delicately
 removing the column from the nest (Fig. 1, in red), in a fast and smooth
 movement, we dropped the cadavers through the hole and immediately closed
 them with a circular plug (Fig. 1, in blue). As the video recordings were
 launched before the introduction of corpses, we could observe the first
 workers who came into contact with corpses. Workers’ behaviour was filmed
 continuously for four hours (10:00 to 14:00) and thereafter for three
 minutes every half hour for another four hours. After the last cadaver was
 discarded outside the nest, the roof plug was gently replaced by the
 column piece in order to create an empty space for the second insertion of
 sporulating bodies. After two days of rest (Fig. 2), 10 sporulating
 cadavers were introduced on day 11 following the same procedure as
 described above. For both uninfected and sporulating corpses, we measured
 the time elapsed before they were removed from the nest, the identity of
 the workers that interacted with them, and the time, number, and type of
 interactions that each tagged worker had with the corpses. Any interaction
 lasting more than two seconds was recorded as contact, regardless of
 whether the ant touched the corpse with its antennae or mandibles.
 Interactions lasting less than two seconds were not considered. If the
 worker grabbed the corpse with its mandibles and moved it from its
 location, the interaction was considered as a displacement. The last
 displacement of a corpse that carried the cadaver outside the nest was
 considered as a discarding. <em>2.3.5 Session 3:
 Mortality and sporulation</em> From days 5 to 21,
 the bodies of the dead workers were removed from the tray each morning.
 For each cadaver, we identified the dead worker by its tag (if present),
 and we determined the cause of death by placing it in sporulation
 following the Lacey method, as described above [54]. The sporulation
 status of the corpses was monitored for two weeks by placing them in a
 dark, thermoregulated cabinet at 20°C. <em>2.4.
 Statistical analyses</em> All statistical
 analyses were conducted using RStudio software (RStudio Desktop
 v1.3.1056). The graphs and tables were created using Excel and R
 (<em>ggplot2</em> and <em>flexplot
 </em>functions). The R code used to perform these analyses is
 provided in the supplementary materials for the reader's
 reference. <em>2.4.1 Behavioural profile and
 assignment to a functional group</em> Firstly, in
 order to determine the functional groups, behavioural data from all the
 tagged individuals from the five colonies were pooled to perform a
 Principal Component Analysis (stats package, princomp function). Based on
 the results of this analysis and data from the existing literature ([6],
 [55-60]), five different functional groups were identified: Foragers,
 Intermittent-foragers, Domestics, Nurses and Inactives (see the Results
 section). Secondly, in order to assign each tagged
 individual to one of the five functional groups, we used the dataset from
 its own colony, as this is the relevant level of study when examining work
 organisation. As brood care was observed to be a relatively rare
 behaviour, workers that spent at least 5% of their time taking care of
 brood were defined as nurses All other tagged workers were assigned to one
 of the four other functional groups by means of a centroid cluster
 analysis performed on their colony dataset (factoextra package, kmeans
 function). The procedure resulted in a well-balanced proportion of each of
 the five functional groups in each of the five colonies (for further
 details, refer to the SI). To test for possible changes
 in the behavioural profiles of tagged workers over the three days of
 observation, a Friedman test (friedmann.test function) was conducted,
 followed by post hoc analysis using pairwise Wilcoxon-Mann-Whitney tests
 (pairwise.wilcox.test function). We also conducted Kruskal-Wallis tests to
 compare behavioural profiles across colonies (kruskal.test function),
 followed by post-hoc Nemenyi tests (kwAllPairsNemenyiTest function).
 Further details are provided in the supplementary (SI Fig. 3).
 <em>2.4.2 Necrophoresis</em> The
 number of contacts with cadavers was compared across functional groups
 with a Kruskal-Wallis test followed, if significant, by pairwise
 comparisons using the Nemenyi Test. Owing to the many tied values, we used
 a correction procedure by randomizing the rank of those ties 50 times and
 keeping only the highest p-value obtained (<em>rank</em>
 function, ties.method = random). The proportion of tagged individuals
 contacting corpses or not was tested in each functional group using a
 Chi²<em> </em>test followed by pairwise Chi² independence
 tests with “False Discovery Rate” correction as post hoc tests (functions:
 <em>chisq.test </em>and<em>
 pairwiseNominalIndependence</em>, method =
 <em>fdr</em>). The same statistical analyses were applied to
 the proportion of tagged individuals in each functional group that
 displaced corpses (functions: <em>chisq.test
 </em>and<em> pairwiseNominalIndependence</em>,
 parameters; chisq = T, method = <em>fdr</em>). Since the same
 tagged workers were exposed to non-infected and sporulating corpses, the
 proportion of individuals contacting/displacing cadavers were compared
 between those two conditions using McNemar test (mcnemar.test
 function). <em>2.4.3 Mortality and Prophylactic
 grooming</em> The survival curves were compared
 across functional groups using Kaplan-Meier tests (<em>survfit
 </em>function). The same methodology was employed to control for the
 colonial effect on survival curves, with no significant differences
 observed between the five colonies (SI Fig. 5, Kaplan-Meier, n.s.). To
 assess whether different levels of exposure to the corpses had an impact
 on the mortality of workers, we performed Chi²<em> </em>test
 followed whenever needed by pairwise Chi² independence tests as post hoc
 (functions: <em>chisq.test </em>and<em>
 pairwiseNominalIndependence</em>, method =
 <em>fdr</em>). Wilcoxon tests were also
 conducted to determine whether workers who contacted corpses exhibited
 higher levels of self-grooming or mobility, prior to the introduction of
 cadavers, than workers that did not contact them
 (<em>wilcox.test</em> function). Finally, we tested the
 potential correlation between the time a worker spends grooming itself and
 their mobility. To this end, we employed the Pearson correlation
 (ggscatter function, cor.method = "pearson").
description: # Social Organization of Necrophoresis: Insights Into Disease Risk
 Management in Ant Societies
 [https://doi.org/10.5061/dryad.m63xsj49w](https://doi.org/10.5061/dryad.m63xsj49w) The dataset contains four files: * The 'R script' file contains the R script used to perform the statistical analysis for the paper. * The 'R tables' file contains the .txt tables necessary to run the R script. * The 'Excel Main Table' spreadsheet contains the main data table and some sub-tables with the unprocessed figures derived from them. * The 'Excel SI Table' spreadsheet contains additional data tables and the unprocessed figures used in the Supplementary Information. ## Description of the data and file structure * The R script, combined with the R tables file, is ready to use and will guide you through the analysis of the data and the production of the figures presented in the paper and generated in R. The script begins with general information, followed by an index table to guide you through the statistical analysis. In Chapter I, the script prompts you to load the necessary packages to run the analysis. The script then follows the same structure as the paper's results: * II) Behavioral Analysis to determine the 5 functional groups.  * III) Necrophoresis analysis.  * IV) Mortality.  * V) Prophylactic grooming and movement. **Note**: To run the script, all the .txt tables in the 'R tables' file must be in your R directory. The script was created using RStudio Desktop v1.3.1056. --- * The 'R tables' file contains four kinds of tables. After the table descriptions, you will find a glossary of every variable used in the .txt tables:  * **"ExcelFinalSansC5"**: The main table with all the unprocessed data. * **"ExcelFinalColoXsansNurse5%" (X = 1 to 5 for each colony)**: Five tables in which workers from the Nurse functional group are excluded, used for the Centroid cluster analysis. * **"DataFriedX" (X = C/F/I/N/P for each functional group)**: Five Tables where workers’ behavioral profiles are divided by analysis day (1 to 3). These tables are used in the script for Friedman tests. * **"Datacat"**: Includes four specific variables transformed into categorical data ('TpsNcat,' 'TpsCcat,' 'NbrNcat,' 'NbrCcat'). This table is used in the script to analyse the effect of number of both contact and time of contact on mortality. **Glossary  of variables:** * **ID**: Tag identification of each individual analyzed during the experiment. The first number represents the colony number, followed by letters denoting the colors of the individual's tag in order: R = Red, B = Blue, J = Yellow, V = Green, W = White. * **Forage**: Proportion of time each individual spent performing 'Foraging' behavior. * **Care**: Proportion of time each individual spent performing 'Brood care' behavior. * **Selfgroom**: Proportion of time each individual spent performing 'Self-grooming' behavior. * **Inactive**: Proportion of time each individual spent inactive. * **AllogroomG**: Proportion of time each individual spent performing 'Allo-Grooming' behavior * **Trophallaxis**: Proportion of time each individual spent performing 'Trophallaxis' behavior. * **Feed**: Proportion of time each individual spent eating. * **Move**: Proportion of time each individual spent moving. * **TpsN**: Total time spent in contact with uninfected cadaver (in seconds), calculated by summing the interaction times each worker had with each uninfected cadaver items in the nest. * **NbrN**: Number of contacts each individual had with uninfected cadavers. * **MoveN**: Number of times each individual moved an uninfected cadaver. * **ProbaN** = MoveN / NbrN * **SortiesN**: Number of times each individual discarded an uninfected cadaver. * **TpsC**: Total time spent in contact with sporulating cadaver (in seconds), calculated by summing the interaction times each worker had with each sporulating cadaver items in the nest. * **NbrC**: Number of contacts each individual had with sporulating cadavers.  * **MoveC**: Number of times each individual moved a sporulating cadaver. * **ProbaC**= MoveC / NbrC * **SortiesC**: Number of times each individual discarded a sporulating cadaver. * **Colony**: Colony number. * **Status**: Survival status. * **Dead**: The individual died during the experiment. * **Alive**: The individual survived until the end of the experiment. * **LostTag**: The individual's tag was recovered during the experiment, and survival status is uncertain. * **DayAfterInfection**: The day of the experiment when the '**Status**' occurred. If alive, this is simply the last day of the experiment ('11'). If LostTag, it is 'NA'. * **Zone**: Indicates the worker’s initial location before tagging (F = foraging area, I = interior of the nest). * **Sporulation**: Indicates whether the worker's body sporulated after death ('oui' = yes, 'non' = no, 'NA' = Not Available). * **AllogroomR**: relic from behavioural analysis meaning 'Allogrooming Received Passively,' later merged with inactivity. * **Groomext**: relic from behavioural analysis meaning 'Extensive Grooming,' later merged with self-grooming.  * **Selfgroom**: relic from behavioural analysis, is equal to the 'Self-grooming' proportion minus the 'Extensif grooming' proportion.       * **DendroB**: The functional group assigned to each worker using a centroid clustering methode presented in the article's methodology.  * **Inactive**: Worker with low activity levels. * **Forager**: Worker spending most of its time outside the nest. * **Nurse**: Worker taking care of the brood. * **Cleaner**: Became 'Domestic' in the paper. Worker extensively performing self-grooming and movement. * **Pre-forager**: Became 'Intermittent-forager' in the paper. Worker dividing its time between the inside and outside of the nest.          * **DendroA** : Earlier clustering method using dendrograms, later replaced by the centroid clustering method in **DendroB**.    * **ContactN**: Binary variable. If the worker contacted at least 1 Uninfected cadaver = 'Yes', if the worker did not ='No'      * **ContactC**: Binary variable. If the worker contacted at least 1 Sporulating cadaver = 'Yes', if the worker did not ='No'           * **MoveN2**: Binary variable. If the worker moved at least 1 Uninfected cadaver = 'Yes', if the worker did not ='No'             * **MoveC2**: Binary variable. If the worker moved at least 1 Sporulating cadaver = 'Yes', if the worker did not ='No'              * **Status0**: Survival status (0 = Survived, 1 = Died, NA= Lost tag)            * **Time**: Day of the experiment when the '**Status0**' occurred.For survivors, this is the last day of the experiment ('11'), and for LostTag, it is 'NA'. * **TpsNcat** : Categorical versions of **TpsN** * '**0s**' = No contact with cadavers * '**1_to_60s**' **=** 1 to 60 seconds of contact with cadavers * '**60s_or_more**' = More than 60 seconds of contact with cadavers * **TpsCcat**: Categorical versions of **TpsC** * '**0s**' = No contact with cadavers * '**1_to_60s**' **=** 1 to 60 seconds of contact with cadavers * '**60s_or_more**' =more than 60 seconds of contact with cadavers * **NrbNcat**: Categorical versions of **NrbN** * **'0_contact'** = No contact with cadavers * '**1_to_5_contacts**'  = 1 to 5 contact with cadavers * '**5_contacts_or_more**' = more than 5 contact with cadavers * **NrbCcat**: Categorical versions of **NrbC** * **'0_contact'** = No contact with cadavers * '**1_to_5_contacts**'  = 1 to 5 contact with cadavers * '**5_contacts_or_more**' = more than 5 contact with cadavers --- * The 'Excel Main Table' contains the main data table, with factors in columns and individuals in rows. Below are descriptions of each column in the file: * **ID**: Tag identification of each individual analyzed during the experiment. The first number represents the colony number, followed by letters denoting the colors of the individual's tag in order: R = Red, B = Blue, J = Yellow, V = Green, W = White. * **Forage**: Proportion of time each individual spent performing 'Foraging' behavior. * **Care**: Proportion of time each individual spent performing 'Brood care' behavior. * **Selfgroom**: Proportion of time each individual spent performing 'Self-grooming' behavior. * **Inactive**: Proportion of time each individual spent inactive. * **AllogroomG**: Proportion of time each individual spent performing 'Allo-Grooming' behavior * **Trophallaxis**: Proportion of time each individual spent performing 'Trophallaxis' behavior. * **Feed**: Proportion of time each individual spent eating. * **Move**: Proportion of time each individual spent moving. * **TpsN**: Total time spent in contact with uninfected cadaver (in seconds), calculated by summing the interaction times each worker had with each uninfected cadaver items in the nest. * **NbrN**: Number of contacts each individual had with uninfected cadavers. * **MoveN**: Number of times each individual moved an uninfected cadaver. * **ProbaN** = MoveN / NbrN * **SortiesN**: Number of times each individual discarded an uninfected cadaver. * **TpsC**: Total time spent in contact with sporulating cadaver (in seconds), calculated by summing the interaction times each worker had with each sporulating cadaver items in the nest. * **NbrC**: Number of contacts each individual had with sporulating cadavers.  * **MoveC**: Number of times each individual moved a sporulating cadaver. * **ProbaC**= MoveC / NbrC * **SortiesC**: Number of times each individual discarded a sporulating cadaver. * **Colony**: Colony number. * **Status**: Survival status. * **Dead**: The individual died during the experiment. * **Alive**: The individual survived until the end of the experiment. * **LostTag**: The individual's tag was recovered during the experiment, and survival status is uncertain. * **DayAfterInfection**: The day of the experiment when the 'Status' occurred. If alive, this is simply the last day of the experiment ('11'). If LostTag, it is 'NA'. * **DendroB**: The functional group assigned to each worker using a centroid clustering methode presented in the article's methodology.  * **Inactive**: Worker with low activity levels. * **Forager**: Worker spending most of its time outside the nest. * **Nurse**: Worker taking care of the brood. * **Cleaner**: Became 'Domestic' in the paper. Worker extensively performing self-grooming and movement. * **Pre-forager**: Became 'Intermittent-forager' in the paper. Worker dividing its time between the inside and outside of the nest. --- * The 'Excel SI Table' is divided into several spreadsheets, each named after the SI figure they were used to produce. * **Spreadsheet 1 (SI figure 2)**: Contains each individual’s (ID) behavioral profile (proportion of Forage, Care, Selfgroom, Inactive, AllogroomG, Trophallaxis, Feed, Move), divided across the three days of video analysis. Used to produce SI Figure 2. * **Spreadsheet 2 (SI figure 3)**: Contains a short table with the mean behavioral profile per colony. Used to produce SI Figure 3. * **Spreadsheet 3 (SI figure 4)**: Includes a table with categorized **ProbaN** and **ProbaC** values by frequency in rows (e.g., NA, 0, &gt;0% to 10% or &gt;50%) and functional group in columns (**DendroB**). Contains the first table with **ProbaN** (uninfected corpes) in the first 7 columns and the second table with **ProbaC** (sporulating corpses) in columns H to N.  The first row is partially left blank to differenciate those two tables. The last three rows represent: * **Never contacted** : Total number of worker that never contacted any of the respective types of cadavers * **Contacted never displace** : Total number of worker that contacted corpses but never displace any * **Displace at least once** : Total number of worker that displace at least 1 cadaver.  * **Spreadsheet 4 (SI figure 6)**: Contains a table with the mortality rate per day of the experiment for each colony: * **Planning day**: Detailed descriptions of each day are in the main manuscript's "Figure 2 Experimental Procedure." * **Colony**: Colony number. * **Mortality rate**: Daily and colony-specific mean mortality rates observed during the experiment. This table is used to produce the SI figure n°6.