Personality does not constrain social and behavioural flexibility in African striped mice

Abstract

The development and persistence of personality in nature are counterintuitive because, in heterogeneous environments, personality is expected to limit the degree of behavioural flexibility. Recent work has shown that personality and behavioural flexibility might be linked, but their interaction is not well understood and could be elucidated by studying a socially flexible species. Using well-established tests, we measured the personality traits of activity, boldness, exploration and aggressiveness in free-living striped mice (Rhabdomys pumilio) in South Africa. Specifically, we tested whether personality changes when individuals change their reproductive tactic, either from group-living philopatrics to solitary-living females and roaming males or from nonbreeding philopatrics to breeders. Our results showed that striped mice have personalities: Individuals behaved consistently for all the behavioural traits measured both over time and contexts (breeding to non-breeding season). While most of the personality traits measured remained consistent among tactics, they did not predict which tactic an individual would adopt next, suggesting that environmental conditions rather than personality influence tactic switching. Additionally, we found important differences in the consistency of the behaviours measured between males and females, indicating that sexual selection might play a prominent role in the maintenance of personality in this species. Our study demonstrates that some personality traits can be stable over an entire lifetime even in socially flexible species and that personality does not constrain social flexibility.

Validating standardised personality tests under semi‐natural conditions in wild house mice (Mus musculus domesticus)

“…In the same test apparatus as the open field test, a Lego toy was placed in the centre. The latency until the novel object was touched for the first time, and then the time spent sniffing the new object was measured over a period of 5 min (VerbeekDrent & Wiepkema, ; Yuen et al, ). At the end of the test the setup was cleaned with 30% Ethanol.…”

“…Studies investigating behaviour of wild rodents have used tests adapted from these standardised tests to study the interaction between personality traits and ecological characteristics (Boon, Reale, & Boutin, ; Herde & Eccard, ; Yuen, Pillay, Heinrichs, Schoepf, & Schradin, , ). Common voles ( Microtus arvalis ) were for example found to exhibit seasonal differences in activity, measured as number of movements and number of barrier crosses and boldness, measured as latency to move and cross a barrier in an open field and a barrier crossing test (Herde & Eccard, ).…”

“…Common voles ( Microtus arvalis ) were for example found to exhibit seasonal differences in activity, measured as number of movements and number of barrier crosses and boldness, measured as latency to move and cross a barrier in an open field and a barrier crossing test (Herde & Eccard, ). Red squirrel exploration (a composite principal component score) of an open field was found to affect habitat use and survival (Boon et al, ) while boldness/ activity in an open field and exploration of a novel object were not related to the use of reproductive tactics as indicated by stability of personality traits across tactic switches in African striped mice ( Rhabdomys pumilio , Yuen, Pillay, Heinrichs, Schoepf, & Schradin, ). The different interpretations (activity, exploration, boldness) of behaviours taken from the same standardised test setups such as the open field test, indicate the difficulty to relate standardised laboratory test setups to ecologically relevant situations.…”

“…Common voles (Microtus arvalis) were for example found to exhibit seasonal differences in activity, measured as number of movements and number of barrier crosses and boldness, measured as latency to move and cross a barrier in an open field and a barrier crossing test (Herde & Eccard, 2013). Red squirrel exploration (a composite principal component score) of an open field was found to affect habitat use and survival (Boon et al, 2008) while boldness/ activity in an open field and exploration of a novel object were not related to the use of reproductive tactics as indicated by stability of personality traits across tactic switches in African striped mice (Rhabdomys pumilio, Yuen, Pillay, Heinrichs, Schoepf, & Schradin, 2015 (Carter, Feeny, Marshall, Cowlishaw, & Heinsohn, 2013) and the validity of measurements from standardised laboratory test setups to reflect natural behaviour (Arvidsson, Adriaensen, Dongen, Stobbeleere, & Matthysen, 2017Lecorps, Kappel, Weary, & Keyserlingk, 2018Yuen, Pillay, Heinrichs, Schoepf, & Schradin, 2016 (Arvidsson et al, 2017, Lecorps et al, 2018. Arvidsson et al (2017) compared activity measured in a standardised test environment in great tits (Parus major) and compared to an exploration of a semi-natural enclosure.…”

Anxiety and exploratory behavior in the African striped mouse, Rhabdomys, taxa are partially modified by the physical rearing environment

“…However, BALB/c laboratory mice that were reared in enriched conditions (more objects in standard cages) were more anxious than un-enriched mice, but the opposite reaction was treatments. Yet, using similar protocols, studies of captive (Joshi & Pillay, 2016a, 2016bRymer & Pillay, 2012) and wild-caught (Yuen, Pillay, Heinrichs, Schoepf, & Schradin, 2015) striped mice found clear population differences. Perhaps the treatment (adding a platform, either simulating cover or no cover) itself might have increased the anxiety of R. pumilio (i.e., positive genotype-environment effect; Plomin, DeFries, & Loehlin, 1977) or resulted in unmatched treatment effects.…”