DOI: 10.5061/dryad.4b8gthtr2
title: Data from: Mate competition and relatedness among males mediate the evolution of lethal fights in bulb mites

description: Aggression can enhance direct fitness by aiding the aggressor’s in
 securing reproductive resources, but it negatively impacts inclusive
 fitness when directed toward kin. We investigated the trade-off between
 the indirect fitness costs of aggression among kin and the direct benefits
 of increased success in mate competition using the bulb mite Rhizoglyphus
 echinopus, a male dimorphic species in which male fighters kill rivals
 with their modified third legs, while unmodified male scramblers seek
 unguarded females to mate. Our experiments showed that fighter aggression
 was never directed toward females, suggesting that fighter aggression
 evolved as a tactic to monopolize mates. Fighters grab other males before
 killing them, and grabbing behavior increased in the presence of a female,
 regardless of the presence of kin. Scrambler mortality increased with
 fighters’ grabbing activity, but whereas the presence of mate competition
 increased lethal aggression, kinship decreased it, as higher mortality was
 observed among non-kin. These findings suggest that aggressive behavior
 intensifies under mate competition, but the decision to escalate
 aggression to lethal levels is influenced by kinship. In conclusion, this
 study provides insight into the trade-offs underlying kin-discriminatory
 aggression and direct benefits.
description: ## Description of data and files ### MITES Aggression Analysis.R This
 script conducts all multi-model analyses and data visualizations included
 in the manuscript. ### Data\_Main\_Analyses.csv This dataset includes
 three explanatory variables — relatedness, female presence, and fighter
 presence — and three response variables — number of kills, number of grabs
 by fighters, and number of grabs between scramblers. Description of
 columns (variables): * Relatedness: Relatedness between the focal fighter
 and scramblers ("Related" = full-siblings; "Unrelated"
 = non-siblings). * Female: Presence of a female ("Present" or
 "Absent"); the female was unrelated to both the fighter and the
 scramblers. * Fighter: Presence of a focal fighter ("Absent" =
 fighter-absent control groups). * Fighter_family: Family ID of the focal
 fighters. Initially planned for use as a random effect, but it was not
 included in the final model analyses for the response variables below, as
 models without this random effect were more parsimonious. (However, it was
 used as a random effect in the mating-status analysis; see below in 3.
 Data_Mating.csv.) * Killing: Number of dead scramblers per group (maximum
 = 4, as each group included four scramblers). * Grab: Number of observed
 grabbing behaviors by the focal fighter (defined as prolonged handling of
 a scrambler). * Wrestling: Number of grabbing interactions observed
 between scramblers. Recorded only in female-present treatments, as
 scrambler interactions were otherwise brief and lacked typical fight-like
 behavior when no female was present. ### Data\_Mating.csv This dataset was
 used specifically to analyze the killing rate depending on the
 fighters' mating status. Only replicates where fighter mating was
 observed are included. Description of columns (variables): * Relatedness:
 Same as above. * Female: Same as above. * Fighter_ID: Family ID of the
 focal fighters. Included as a random effect, as "Before" and
 "After" observations are paired within each fighter family. *
 Mating: Mating status of the fighter ("Before" or
 "After" mating). * Killing: Number of dead scramblers in the
 group for the given duration. * Duration: Number of days over which deaths
 occurred, before and after mating. (Duration varied because mating
 occurred on different days across replicates.) * Killing_rates: Killing
 (number of scrambler deaths) divided by Duration (number of days). This
 was calculated to graphically represent the combined effects of mating
 status and duration, especially given the small sample size.