DOI: 10.5061/dryad.2547d7wz2
title: Data from: Among-individual behavioural variation in the ornamental red cherry shrimp, Neocaridina heteropoda

description: Personality variation, defined as among-individual differences in
 behaviour that are repeatable across time and context, has been reported
 across animal taxa. From an evolutionary
 perspective, characterising the amount and structure of this
 variation is useful since differences among-individuals are the raw
 material for adaptive behavioural evolution. However, it is becoming
 apparent that behavioural variation among-individuals also has
 implications for more applied areas of evolution and ecology – from
 invasion biology, to ecotoxicology, and selective breeding in captive
 systems. Here, we investigate the structure of personality variation in
 the red cherry shrimp, Neocaridina heteropoda, a popular ornamental
 species that is readily kept and bred under lab conditions and is emerging
 as a decapod crustacean model across these fields, but for which basic
 biological, ecological, and behavioural data is limited. Using two assays
 and a repeated measures approach, we quantify behaviours putatively
 indicative of shy-bold variation and test for sexual dimorphism and/or
 size-dependent behaviours (as predicted by some state-dependent models of
 personality). We find moderate to high
 behavioural repeatabilities across traits. Although strong
 individual level correlations across behaviours are consistent with a
 major personality axis underlying these observed traits, the multivariate
 structure of personality variation does not fully match a priori
 expectations of a shy-bold axis. This may reflect our
 ecological naivety with respect to what really constitutes bolder, more
 risk prone, behaviour in this species.  We find no
 evidence for sexual dimorphism and only weak support size-dependent
 behaviour.  Our study contributes to the growing literature
 describing behavioural variation in aquatic invertebrates. Furthermore, it
 lays a foundation for further studies harnessing the potential of this
 emerging model system. In particular, this existing behavioural variation
 could be functionally linked to life-history traits and invasive success,
 and serve as target of artificial selection or bioassays. It thus holds
 significant promise in applied research across ecotoxicology, aquaculture,
 and invasion biology.
description: Refer to Methods in the associated manuscript.
description: # Among-individual behavioural variation in the ornamental red cherry
 shrimp, Neocaridina heteropoda  Authors Rosie A. Rickward, F.
 Santostefano, Alastair J. Wilson,  Data Collection - Rosie A. Rickward
  Code writing - Rosie A. Rickward, Francesca Santostefano, Alastair J.
 Wilson   data file name - 'raw.data.sheet.csv' Column headers
 with explanations:  ID: The identity assigned to each shrimp date: date
 the assay took place time.x: The time of day each trial took place
 tracklength: The total difstance travelled (cm) in the OFT trial
 wall_dist: The Average distance away from tank walls (cm) in the OFT trial
 area: The proportion of the total arena covered (%) in the OFT trial
 Trial.x: The type of assay and the trial repeat number time_arena: Time
 spent in the trackable part of the arena in the FST trial tl_arena:
 Distance travelled while outside shelter and food zones (cm) in the FST
 trial frz_arena: The total number of freezes in the arena in the FST
 trial. Defined as speed dropping &lt;4cm. s-1 for ≥25s shelter_duration:
 The total time spent in the shelter (s) in the FST trial Set.Up: The
 experimental arena used (tank A vs Tank B) Order: Reflecting the order of
 individuals tested between experimental water changes (from 1-6) Sex.mm:
 Sex recorded for each shrimp estimated from external morphology, after
 each trial estimated.sex1: Assigned single sex determination of a male or
 female if ≥5/6 trial-specific assessments were in agreement. We assigned
 sex as ‘unknown’ if this criterion was not met size: The length of each
 shrimp (from the tip of the rostrum to the posterior end of the telson to
 the nearest 0.001mm) recorded at the end of each trial weight: The masss
 of each shrimp (to the nearest 0.01g) recorded at the end of each trial
 OFT_tot_frz: The total number of freezes in the OFT trial. Defined as
 speed dropping &lt;4cm. s-1 for ≥25s food_latency2: Time to first entry of
 the food zone (s) in the FST trial Missing data code: NA Additional
 information: definition of transformed variables used for the final
 analyses - variables are transformed within the provided R script based on
 the raw data above replicate: Trial repeat number for each individual
 (from 1-3) res: Time of day each trial took place after transformation to
 minutes after midnight tracklength3: The square root transformation and
 scaling to standard deviation units of 'tracklength' area2:
 Scaling to standard deviation units of 'area' wall_dist2: The
 log transformation and scaling to standard deviation units of
 'wall_dist' freez2: The square root transformation, sign
 reversal and scaling to standard deviation units of
 'OFT_tot_frz' dur_NIS2: Time spent outside the shelter zone (s)
 in the FST trial (240-'shelter_duration'). This was then square
 root transformed and scaled to standard deviation units foodlat2: The log
 transformation, sign reversal and scaling to standard deviation units of
 'food_latency2' ATL2: The square root transformation and scaling
 to standard deviation units of 'tl_arena' AFRZ2: The square root
 transformation, sign reversal and scaling to standard deviation units of
 'frz_arena' time_arena_sqrt: The square root transformation of
 'time_arena'