Effects of Personality Traits on the Food-Scratching Behaviour and Food Intake of Japanese Quail (Coturnix japonica)

Overall foraging success and ultimate fitness of an individual animal is highly dependent on their food-searching strategies, which are the focus of foraging theory. Considering the consistent inter-individual behavioural differences, personality may have a fundamental impact on animal food-scratching behaviour, which remains largely unknown. In this study, we aimed to investigate how personality traits (i.e., boldness and exploration) affect the food-scratching behaviour and food intake of the domestic Japanese quail Coturnix japonica during the foraging process. The quails exhibited significant repeatability in boldness and exploration, which also constituted a behavioural syndrome. More proactive, that is, bolder and more explorative, individuals scratched the ground more frequently for food and began scratching earlier in a patch. Individuals that scratched more frequently had a longer foraging time and a higher food intake. The correlation between personality traits and temporary food intake during every 2 min varied over time and was sex dependent, with females exhibiting a positive correlation during the first half of the foraging stage and males after the initial stage. These findings suggest that personality traits affect the food-scratching behaviour and, thus, the food intake of quails. Our study provides insights into the impact of personality traits on animal’s foraging behaviour by influencing their food-searching strategies.

Inter-individual differences of calling and exploratory behaviour in a lebinthine cricket species hint at different mate-finding strategies

Individual fitness can be boosted by behavioural strategies that maximise mate-finding probability while minimising predation risk. Animals that use acoustics to find mates may benefit from using both stationary calling and active exploration, but these also expose them to different types of predators. Studying calling and searching behaviours concurrently allows us to understand their evolutionary trade-offs between survival and reproduction. Unlike most other crickets, lebinthine males alternate between singing and exploration to find females, which offer a unique and excellent opportunity to test for inter-individual differences and behavioural syndrome between call properties and exploratory behaviours. Our data demonstrate that call properties and exploratory behaviour were repeatable. We did not, however, find that call properties correlate with exploration as some consistently exploratory individuals produce longer calls while others produce shorter calls. Our study suggests that lebinthine males use different combinations of calling and exploratory behaviours to cope with unpredictable risk–benefit scenarios.

Male Mate Choice in Mosquitofish: Personality Outweighs Body Size

Background Despite its important implications in behavioural and evolutionary ecology, male mate choice has been little studied, and the relative contribution of personality and morphological traits remains largely unknown. Using standard two-choice mating trials, we studied whether personality traits (i.e. shyness and activity) and body size of both sexes affect mate choice in male mosquitofish Gambusia affinis. Results Both shyness and activity in males were significantly repeatable and constituted a behavioural syndrome. No overall directional preference for large (or small) females with the same activity levels was detected because larger males preferred larger females and smaller males chose smaller females. However, males spent more time associating with active females regardless of their body lengths and had an enhanced preference for inactive females when they increased activity levels. We also found that more proactive (bolder and more active) males had stronger preferences for more active females. Conclusions Our study supports the importance of body size in male mate choice but highlights that personality traits may outweigh body size preferences when males choose mating partners.

Adaptation, Validation and Preliminary Standardisation of the Frontal Systems Behaviour Scale – Apathy Subscale and the Dimensional Apathy Scale in Vietnamese Healthy Samples

Objective: Apathy, the reduction of motivation and goal-directed behaviour, is a ubiquitous behavioural syndrome in many neurological disorders. However, apathy measures are limited in non-English speaking countries. The present study aimed to develop a culturally appropriate version of the Vietnamese Frontal Systems Behavioural Scale-Apathy subscale (V-FrSBe-A) and Dimensional Apathy Scale (V-DAS), examine their internal reliability and construct validity (i.e., factor structure, convergent and divergent validity) in a Vietnamese healthy sample and establish preliminary normative cut-offs for clinical and research applications. Method: In total, 112 healthy subjects and 64 informants completed the self-report and informant report V-FrSBe-A and V-DAS, developed using a translation, back-translation and cultural adaptation procedure. McDonald’s omega was applied to examine internal reliability. The internal structure of the V-DAS was evaluated using exploratory structural equation model. For both apathy scales, convergent validity was determined by correlations between scales and between informant and self-report versions. Regarding divergent validity, participants completed the Vietnamese Depression Anxiety Stress Scale-21 and V-FrSBe-Disinhibition for depression and disinhibition assessment. Results: Both the V-FrSBe-A and V-DAS were reliable (ω t ≥ .74). Dimensional manifestations of apathy in executive, emotional and initiation domains were confirmed on the V-DAS. Both scales were also valid, convergent with each other and divergent from depression and disinhibition symptoms. Cut-off scores for both scales were higher than their English versions. Conclusion: The adapted V-FrSBe-A and V-DAS have good reliability and validity for the potential application in clinical groups to advance current knowledge about apathy transculturally and direct more effective clinical care for Vietnamese individuals with neurological disorders.

Inter-individual behavioural variation in the crested porcupine

In this study, we investigated on the existence of personality in the crested porcupine in Central Italy by measuring variation and repeatability of three behavioural traits. Porcupines were captured through metal traps located around and in the immediate surroundings of the burrows. Then, they were manipulated and set free. Capture and handling were the experimental contexts where we measured exploration, proactivity and aggressiveness of each individual. Our results provided evidence for consistent inter-individual differences in the measured traits, with a high value of individual repeatability in aggressiveness and proactivity. The positive correlation between traits suggest the existence of a behavioural syndrome, with some individuals more aggressive and active with respect to others.

Behavioural syndromes shape evolutionary trajectories via conserved genetic architecture

Behaviours are often correlated within broader syndromes, creating the potential for evolution in one behaviour to drive evolutionary changes in other behaviours. Despite demonstrations that behavioural syndromes are common, this potential for evolutionary effects has not been demonstrated. Here we show that populations of field crickets ( Gryllus integer ) exhibit a genetically conserved behavioural syndrome structure, despite differences in average behaviours. We found that the distribution of genetic variation and genetic covariance among behavioural traits was consistent with genes and cellular mechanisms underpinning behavioural syndromes rather than correlated selection. Moreover, divergence among populations' average behaviours was constrained by the genetically conserved behavioural syndrome. Our results demonstrate that a conserved genetic architecture linking behaviours has shaped the evolutionary trajectories of populations in disparate environments—illustrating an important way for behavioural syndromes to result in shared evolutionary fates.

Correlations between personality traits and roosting behaviours suggest a behavioural syndrome in little brown bats

Behavioural syndromes are composed of correlated suites of personality traits and can include traits related to the behaviour and ecology of free-ranging animals. We used captive little brown bats (Myotis lucifugus) to test the hypothesis that behaviours measured in standardized tests reflect personality traits and form behavioural syndromes with roosting behaviours. We predicted: (1) measured behaviours would be repeatable; (2) personality traits and roosting behaviours would form behavioural syndromes; and (3) individuals with similar personality scores would associate more strongly. We observed repeatability for some traits and evidence of behavioural syndromes. Activity was strongly repeatable across time and contexts. More central individuals roosted in larger groups, while individuals with high roost-fidelity roosted in larger groups. Individuals with similar activity scores were also more likely to associate in day roosts, suggesting some behavioural assortment. Our results have implications for how behavioural variation might influence transmission of white-nose syndrome.