Effects of social conditions during early development on stress response and personality traits in great tits (Parus major)

Abstract

Environmental conditions during early development play a crucial role in shaping an organism's phenotype. To test how social group size affects stress response and behavioral characteristics, we used great tits (Parus major) from selection lines for exploratory behavior, a proxy for an avian personality trait, and birds from the wild in a brood size manipulation experiment. Nestlings were tested for stress response using an established stress test and after independence subjects were tested for exploratory behavior. Nestlings from small broods showed a stronger stress response than nestlings from normal-sized broods. Exploratory behavior was not affected by brood size but associated with sex ratio in the nest. Birds from female-biased broods became faster explorers than those from male-biased broods. The results demonstrate that early social conditions can affect physiological stress responses in nestlings and that behavioral personality traits measured after fledging can be affected by the social experience in the nest.

The Influence of Rearing on Behavior, Brain Monoamines, and Gene Expression in Three-Spined Sticklebacks

“…More specifically, based on previous work on sticklebacks and other animals, we predicted neophobia would decrease for fish raised with increased simulated predator stress, habitat complexity, or social stress [e.g., Elvidge et al, 2016;Christensen and Nielsen, 2004;Naguib et al, 2011;Bannier et al, 2017]. We found that fish raised in complex physical or socially stressful environments were less neophobic, confirming our predictions and matching findings also in birds [Christensen and Nielsen, 2004].…”

“…DOI: 10.1159/000489942 Lima and Dill, 1990;Bell and Sih, 2007;Naguib et al, 2011;Taborsky and Oliveira, 2012]. We found that fish raised in complex physical environments were more aggressive, and fish in our other early environmental treatments did not differ in aggression relative to control fish.…”

“…Additionally, more complex physical or social environments can alter individuals' behavior [van Praag et al, 2000;Christensen and Nielsen, 2004;Lazic et al, 2007;Patzke et al, 2009], where individuals exposed to more complex environments tend to increase in exploratory behavior and decrease in neophobia [Christensen and Nielsen, 2004]. Further, aspects of early social environment can influence exploration [Naguib et al, 2011]. Despite these findings that a variety of environmental aspects influence behavioral responses, little is known about the mechanisms translating early environmental variation into behavioral differences later in life.…”

“…Sticklebacks are a mobile species and exploration is required to find both food and mates; aggression is likely important for both social interactions and for males to establish breeding burrows and attract females; and neophobia is important for avoiding predators [e.g., Ostlund-Nilsson et al, 2007]. Based on previous work, we predict that exposure to predation stress increases aggressiveness [Lima and Dill, 1990;Bell and Sih, 2007] and neophobia [e.g., Elvidge et al, 2016], and decreases exploration [e.g., Abbey- Lee et al, 2016;Moses and Sih, 1998;Hedrick and Kortet, 2006]; exposure to habitat complexity increases exploration behavior and decreases neophobia [e.g., Christensen and Nielsen, 2004]; and exposure to variable social environment increases aggression and decreases neophobia [e.g., Bannier et al, 2017;Naguib et al, 2011]. Additionally, we predict that monoamine levels, their metabolites, and the expression of genes related to monoaminergic transmission will vary in the brain depending on early environmental treatment, but, as the relationship between the environment and monoaminergic systems is not well understood, we have no directional predictions [Winberg and Nilsson, 1992;Carere and Maestripieri, 2013].…”

Early development influences ontogeny of personality types in young laboratory rats

“…Dimitsantos et al, 2007). Surely, we cannot rule out that potential epigenetic or neuroendocrine correlates of early life conditions, in particular of sibling number or litter size, might also be involved in shaping the behavioral development of the young (Champagne, 2008;Koolhaas et al, 1999;Koolhaas, de Boer, Coppens, & Buwalda, 2010;Naguib, Flörcke, & van Oers, 2011;Rödel et al, 2010;Sachser et al, 2011;Siegeler, Sachser, & Kaiser, 2011). However, due to the strong effects of starting body mass-overriding the effects of litter size-we suggest that the individual body mass and size directly and causally affect the ontogeny of personality traits.…”