DOI: 10.5061/dryad.44j0zpchh
title: Data for: Weak, but not strong, ties support coalition formation among wild female chimpanzees

description: In social species, individuals may be able to overcome competitive
 constraints on cooperation by leveraging relationships with familiar,
 tolerant partners. While strong social ties have been linked to
 cooperation in several social mammals, it is unclear the extent to which
 weak social ties can support cooperation, particularly among non-kin. We
 tested the hypothesis that weakly affiliative social relationships support
 cooperative coalition formation using 10 years of behavioural data on wild
 female chimpanzees. Female chimpanzees typically disperse and reside with
 non-kin as adults. Their social relationships are differentiated but often
 relatively weak, with few dyads sharing strong bonds. Females occasionally
 form aggressive coalitions together. Three measures of relationship
 quality - party association, five-meter proximity, and whether a dyad
 groomed - positively predicted coalitions, indicating that relationship
 quality influenced coalition partnerships. However, dyads that groomed
 frequently did not form more coalitions than dyads that groomed
 occasionally, and kin did not cooperate more than expected given their
 relationship quality. Thus, strong bonds and kinship did not bolster
 cooperation. We conclude that cooperative coalitions among female
 chimpanzees depend on social tolerance but do not require strong bonds.
 Our findings highlight social tolerance as a distinct pathway through
 which females can cultivate cooperative relationships.
description: This data is comprised of behavioral data on adult female
 chimpanzees living in Kibale National Park from 2010-2019. For analysis 1
 (long term correlational analysis), behavioural observations are
 summarized into dyadic rates and counts of behaviors per two year time
 periods. This includes the number of times the dyad was in the same party,
 the number of coalitions the dyad engaged in together, a five-meter
 association index, a grooming duration index, whethere or not the dyad
 ever groomed dudring the period (0/1) the combined rank of the dyad,
 whether the dyad involved any immigrant females, whether the dyad
 consisted of females related to each other, and the total time the dyad
 was in the same party when one of females was the focal. For analysis 2
 (partner selection analysis), data is organized per dyad at each coalition
 event. This dataset includes relevant information about the dyad as in
 analysis 1, but also indicates which dyad formed the coalition out of all
 available partners at the time of the coalition event. 
description: R free statistical computing software The
 following R libraries:  library(tidyverse)
 library(lme4) library(DHARMa)
 library(effects) library(ggeffects)
 library(MuMIn) library(gridExtra)
 library(MuMIn) library(grid)
 library(cowplot) library(emmeans)
 library(progress) ymd &lt;-
 lubridate::ymd mdy &lt;- lubridate::mdy
 month &lt;- lubridate::month year
 &lt;- lubridate::year ymd_hms &lt;-
 lubridate::ymd_hms hms &lt;-
 lubridate::hms select &lt;- dplyr::select
 filter &lt;- dplyr::filter contr &lt;-
 glmerControl(optimizer = "bobyqa", optCtrl =
 list(maxfun=2e5))