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Abstract Colour polymorphic species often exhibit variation in morphology, physiology, and behaviour among morphs. In particular, dominance status may be signalled by the interaction between behaviour and colour morph. Behavioural traits associated with dominance include boldness, exploration, and aggression, which influence access to preferred habitat, territorial defence, and mate acquisition. In ectotherms, the social structure associated with morphs may result in the exploitation of structural niches differing in thermal quality. Hence, social interactions among morphs may generate concordant variation in thermal preference and environmental temperature. However, few studies have assessed thermal preference variation in colour polymorphic species and its covariation with behaviour. Doing so can provide insight into niche specialization and the maintenance of colour polymorphism in populations. Here, we investigated the patterns of covariation in boldness behaviour, exploratory behaviour, and thermal preference in the tree lizard,Urosaurus ornatus. We assessed trait variation between territorial and non‐territorial male morphs and between orange and yellow female morphs. Boldness and exploratory behaviour were repeatable in maleU. ornatusand bolder individuals were significantly more likely to incur tail loss, a potential consequence of bold behaviour. Territorial male morphs were significantly bolder and more exploratory and preferred higher body temperatures with a narrowerTsetthan non‐territorial morphs. Female morphs did not vary in behavioural or thermal traits. This study highlights behavioural mechanisms that underly ecological niche segregation and variable habitat use between morphs in a colour polymorphic species.
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This content will become publicly available on June 1, 2026
Do differences in exploration and boldness inform species level responses to environmental change in montane chipmunks?
How animals behave in novel situations may significantly affect multiple aspects of their biology, including how they respond to environmental change. Two aspects of behaviour that are often used to assess interactions with new environments are exploration and boldness. Within species, variation in these responses to novelty is thought to reflect differences in individual behavioural phenotypes (e.g. behavioural syndromes). Between species, these responses may be influenced by the degree of ecological specialization, with members of more specialized taxa typically expected to display a reduced tendency to interact with novel habitats. To test the prediction that more ecologically specialized species are more neophobic, we used open-field assays to compare exploratory behaviour and boldness among free-living members of two partially sympatric species of chipmunks from the Sierra Nevada Mountains of California, U.S.A.: the lodgepole chipmunk, Tamias speciosus, a habitat generalist, and the alpine chipmunk, Tamias alpinus, a habitat specialist. Our analyses indicate that while behavioural measures of boldness did not differ between these species, individual T. speciosus were on average more exploratory than individual T. alpinus. Although the number of individuals tested per species was limited, these findings have important implications for understanding reported interspecific differences in elevational range shifts in response to changing environmental conditions in the Sierra Nevada. More generally, our analyses underscore the potential importance of behavioural responses to novelty in shaping species level patterns of response to environmental change.
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- Award ID(s):
- 2305665
- PAR ID:
- 10629471
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Animal Behaviour
- Volume:
- 224
- Issue:
- C
- ISSN:
- 0003-3472
- Page Range / eLocation ID:
- 123159
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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