Consistency in boldness, activity and exploration at different stages of life

Antje Herde,Jana A Eccard

doi:10.1186/1472-6785-13-49

Abstract

BackgroundAnimals show consistent individual behavioural patterns over time and over situations. This phenomenon has been referred to as animal personality or behavioural syndromes. Little is known about consistency of animal personalities over entire life times. We investigated the repeatability of behaviour in common voles (Microtus arvalis) at different life stages, with different time intervals, and in different situations. Animals were tested using four behavioural tests in three experimental groups: 1. before and after maturation over three months, 2. twice as adults during one week, and 3. twice as adult animals over three months, which resembles a substantial part of their entire adult life span of several months.ResultsDifferent behaviours were correlated within and between tests and a cluster analysis showed three possible behavioural syndrome-axes, which we name boldness, exploration and activity. Activity and exploration behaviour in all tests was highly repeatable in adult animals tested over one week. In animals tested over maturation, exploration behaviour was consistent whereas activity was not. Voles that were tested as adults with a three-month interval showed the opposite pattern with stable activity but unstable exploration behaviour.ConclusionsThe consistency in behaviour over time suggests that common voles do express stable personality over short time. Over longer periods however, behaviour is more flexible and depending on life stage (i.e. tested before/after maturation or as adults) of the tested individual. Level of boldness or activity does not differ between tested groups and maintenance of variation in behavioural traits can therefore not be explained by expected future assets as reported in other studies.

Highlights

Animals show consistent individual behavioural patterns over time and over situations
We investigated the consistency over time in four behavioural tests, and used common voles (Microtus arvalis) in different life stages as a model organism
For the animals tested ‘over maturation’ correlations between the first and second round were found in the latency of the barrier test but not its activity

Summary

Introduction

Animals show consistent individual behavioural patterns over time and over situations. This phenomenon has been referred to as animal personality or behavioural syndromes. Animals of the same sex, weight, and population often differ consistently in their aggressiveness in different situations. This phenomenon has been referred to as behavioural syndromes [1,2,3] or animal personalities [4,5]. Studies on consistency over time in birds [19,20] and insects [21,22,23] showed that stability and repeatability is variable for different behaviours and for the species under investigation. It cannot generally be assumed that consistent individual differences in behaviour are stable throughout life and a validation for different behaviours, life stages and species is necessary

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