DOI: 10.5061/dryad.cg464
title: Data from: Ecological context and the probability of mistakes underlie speed choice

description: 1.Movement is fundamental to the ecology of animals, and an animal's
 choice of movement speed determines the duration, energetic costs, and
 probability of success of any given activity. It is often assumed that
 animals should use maximum speeds when escaping from predators, but an
 increasing number of studies find animals rarely move as fast as they can
 in nature because faster speeds come with a greater chance of mistakes.
 Mathematical modelling suggests that, when escaping predators, prey
 animals should optimise speeds to simultaneously outrun their pursuer and
 minimise their probability of slipping. This can be particularly important
 when running along narrow structures like branches. When foraging,
 however, animals should avoid moving at high speeds, which are often
 energetically costly and decrease the ability to detect food or predators.
 2.In this study, we examined how trade-offs between speed and probability
 of slipping influenced the speed choice of wild antechinus (Antechinus
 mysticus) during escaping and foraging behaviours. We also examined how
 this trade-off affected foraging behaviour. 3.Antechinus ran significantly
 faster when escaping (1.207 ± 0.033 ms-1) than foraging (0.145 ± 0.002
 ms-1), and slipped 37% more often during escapes. However, foraging
 antechinus still slipped frequently on narrow branches, despite running an
 order of magnitude more slowly than they did on wide branches.
 Furthermore, antechinus slipped at lower speeds when foraging than they
 did when escaping, suggesting that avoiding mistakes is less highly
 prioritized when foraging. 4.Antechinus visited the feeding station
 accessed by a wide branch more frequently (and ate more while there)
 compared with feeding stations accessed by narrow branches, even when
 those branches were 33% or 67% shorter. This suggests that foraging
 decisions may be based on potential limitations to speed and the
 probability of slipping over distance to cover. 5.Though activities such
 as running can be fundamental to animals’ fitness, a general framework to
 understand how animals select speeds in nature is still being developed.
 We test the assumption that animals choose running speeds to minimise
 their motor mistakes, and demonstrate the cost of mistakes is likely to be
 different across ecological and behavioural contexts.
description: Foraging
 preferencesThis file contains the
 data used to analyse the foraging preferences of buff-footed antechinus
 (Antechinus mysticus) foraging along narrow and wide beams of varying
 length. It contains: individual antechinus ID, sex, mass (g), beam type,
 beam diameter (mm), beam length (m), beam position within the experimental
 enclosure, proportion of food eaten from the platform at the end of the
 beam, proportion of time spent at the platform at the end of the beam, and
 proportion of total visits made to the platform at the end of the
 beam.Escape
 behaviourThis file contains the
 stride-by-stride data used to analyse the escape speeds and behavioural
 decisions of buff-footed antechinus (Antechinus mysticus) escaping along
 narrow and wide beams. It contains: individual antechinus ID, sex, mass
 (g), beam diameter (mm), trial number, stride number, maximum stride
 velocity (ms-1), presence of a slip, time to return to 1.1 ms-1 after the
 slip, strides to return to 1.1 ms-1 after the slip, and whether or not the
 animal ever returned to 1.1 ms-1 after the slip.Foraging behaviour and
 experiment comparisionsThis file contains the
 data used to analyse the foraging movement speeds and behavioural
 decisions of buff-footed antechinus (Antechinus mysticus) foraging on
 narrow and wide beams. It also contains comparative data for escaping
 antechinus, to compare foraging and escape movement decisions. It
 contains: individual antechinus ID, sex, experiment (foraging or
 escaping), mass (g), beam type, beam diameter (mm), beam length (m), trial
 number, movement speed (ms-1, mean speed over first 20cm of the beam),
 presence of a slip, number of slips, and direction of
 movement.