Urbanization and biological invasion shape animal personalities

Abstract

Novel selective pressures derived from human activities challenge the persistence of animal populations worldwide. Behavior is expected to be a major factor driving animals' responses to global change because it largely determines how animals interact with the environment. However, the role of individual variation in behavior to facilitate the persistence of animals in changing environments remains poorly understood. Here, we adopted an animal personality approach to investigate whether different behavioral traits allow animals to deal with two major components of global change: urbanization and biological invasions. By studying six populations of Anolis sagrei lizards, we found for the first time that anoles vary consistently in their behavior across different times and contexts. Importantly, these animal personalities were consistent in the wild and in captivity. We investigated whether behavioral traits are pulled in different directions by different components of global change. On the one hand, we found that lizards from urban areas differ from nearby forest lizards in that they were more tolerant of humans, less aggressive, bolder after a simulated predator attack, and they spent more time exploring new environments. Several of these risk-taking behaviors constituted a behavioral syndrome that significantly differed between urban and forest populations. On the other hand, the behavior of urban A. sagrei coexisting with the invasive predatory lizard Leiocephalus carinatus was associated with dramatic changes in their foraging niche. Overall, we provide evidence that differences in animal personalities facilitate the persistence of animals under novel selective regimes by producing adaptive behaviors relevant to their ecology such as predator avoidance. Our results suggest that natural selection can favor certain behaviors over others when animals are confronted with different ecological challenges posed by global change. Therefore, we underscore the need to incorporate behavioral ecology into the study of how animals adaptively respond to human-induced environmental changes.

Breath rate of passerines across an urbanization gradient supports the pace‐of‐life hypothesis and suggests diet‐mediated responses to handling stress

“…Finally, urban individuals may show behavioral differences with nonurban individuals (i.e., bold personality, reduced antipredator behavior, and decreased fear to humans) (Charmantier et al., ; Griffin et al., ; Lapiedra, Chejanovski, & Kolbe, ; Samia, Nakagawa, Nomura, Rangel, & Blumstein, ; Sepp et al., ; Sol et al., ; see also Atwell et al., ). However, we found no support to the “habituation‐induced stress response hypothesis.” Species inhabiting natural, rural, and urban locations, and individuals of the same species in rural and urban locations, showed similar BR at handling.…”

Great tits take greater risk toward humans and sparrowhawks in urban habitats than in forests

“…Humans in cities seldom pose direct threat to free‐living animals like birds (Clucas & Marzluff, ); thus, greater risk‐taking (e.g., reduced avoidance) toward humans can be advantageous in urban habitats. Reduced flight responses have been observed in many urban animals (Samia, Nakagawa, Nomura, Rangel, & Blumstein, ), including birds (Carrete & Tella, ; Møller et al, ; Myers & Hyman, ; Vincze et al, ), mammals (McCleery, ; Uchida, Suzuki, Shimamoto, Yanagawa, & Koizumi, ), and reptiles (Lapiedra, Chejanovski, & Kolbe, ; McGowan, Patel, Stroh, & Blumstein, ).…”

Marine subsidies change short‐term foraging activity and habitat utilization of terrestrial lizards

“…Alternatively, if the percentage of attacks that result in successful prey capture is higher in subsidized plots (e.g., because marine‐derived prey are easier to capture than terrestrial prey on average), then foraging in seaweed would not necessarily be associated with increased attack rate. Finally, it is possible that the observed shift in habitat use and activity was due to exploratory behavior by lizards in response to a novel stimulus (i.e., the addition of seaweed) (Lapiedra, Chejanovski, & Kolbe, ). Given that we have previously documented diet shifts in response to subsidy, we suspect that both exploratory and foraging responses are likely involved in the habitat and activity shift.…”