Transgenerational plasticity (TGP) occurs when the environment experienced by a parent influences the development of their offspring. In this article, we develop a framework for understanding the ...mechanisms and multigenerational consequences of TGP. First, we conceptualize the mechanisms of TGP in the context of communication between parents (senders) and offspring (receivers) by dissecting the steps between an environmental cue received by a parent and its resulting effects on the phenotype of one or more future generations. Breaking down the problem in this way highlights the diversity of mechanisms likely to be involved in the process. Second, we review the literature on multigenerational effects and find that the documented patterns across generations are diverse. We categorize different multigenerational patterns and explore the proximate and ultimate mechanisms that can generate them. Throughout, we highlight opportunities for future work in this dynamic and integrative area of study.
A behavioural syndrome occurs when individuals behave in a consistent way through time or across contexts and is analogous to 'personality' or 'temperament'. Interest is accumulating in behavioural ...syndromes owing to their important ecological and evolutionary consequences. There are plenty of opportunities in this burgeoning young field to integrate proximate and functional approaches to studying behaviour, but there are few guidelines about where to start or how to design a study on behavioural syndromes. After summarizing what we do and do not know, this brief review aims to act as a general guide for studying behavioural syndromes. Although the array of possible behavioural combinations can seem overwhelming, there are at least four different strategies that can be used to choose which behaviours or contexts to study in a behavioural syndromes view. I describe the strengths and weaknesses of these non-exclusive strategies, and then discuss the methodological and statistical issues raised by such studies.
Animals in natural populations are constantly managing multiple demands on their time and energy, and decisions about ecologically relevant tradeoffs have important fitness consequences.Growing ...evidence for behavioral syndromes and shared mechanisms underlying behavior in different functional contexts prompts novel hypotheses about how animals balance competing demands.Mechanistic work in humans and model organisms suggests that distinct molecular, neural, and genetic mechanisms are often involved in decision-making, but little is known about variation in those mechanisms or how they evolve.Applying neurogenomic tools to nontraditional model organisms where the ecological constraints are understood has the potential to offer exciting insights into the evolution and adaptive significance of mechanisms for decision-making.
Animals in nature are constantly managing multiple demands, and decisions about how to adjust behavior in response to ecologically relevant demands is critical for fitness. Evidence for behavioral correlations across functional contexts (behavioral syndromes) and growing appreciation for shared proximate substrates of behavior prompts novel questions about the existence of distinct neural, molecular, and genetic mechanisms involved in decision-making. Those proximate mechanisms are likely to be an important target of selection, but little is known about how they evolve, their evolutionary history, or where they harbor genetic variation. Herein I provide a conceptual framework for understanding the evolution of mechanisms for decision-making, highlighting insights on decision-making in humans and model organisms, and sketch an emerging synthesis.
Animals in nature are constantly managing multiple demands, and decisions about how to adjust behavior in response to ecologically relevant demands is critical for fitness. Evidence for behavioral correlations across functional contexts (behavioral syndromes) and growing appreciation for shared proximate substrates of behavior prompts novel questions about the existence of distinct neural, molecular, and genetic mechanisms involved in decision-making. Those proximate mechanisms are likely to be an important target of selection, but little is known about how they evolve, their evolutionary history, or where they harbor genetic variation. Herein I provide a conceptual framework for understanding the evolution of mechanisms for decision-making, highlighting insights on decision-making in humans and model organisms, and sketch an emerging synthesis.
A perplexing new question that has emerged from the recent surge of interest in behavioural syndromes or animal personalities is - why do individual animals behave consistently when behavioural ...flexibility is advantageous? If individuals have a tendency to be generally aggressive, then a relatively aggressive individual might be overly aggressive towards offspring, mates or even predators. Despite these costs, studies in several taxa have shown that individuals that are more aggressive are also relatively bold. However, the behavioural correlation is not universal; even within a species, population comparisons have shown that boldness and aggressiveness are correlated in populations of sticklebacks that are under strong predation pressure, but not in low predation populations. Here, we provide the first demonstration that an environmental factor can induce a correlation between boldness and aggressiveness. Boldness under predation risk and aggressiveness towards a conspecific were measured before and after sticklebacks were exposed to predation by trout, which predated half the sticklebacks. Exposure to predation generated the boldness-aggressiveness behavioural correlation. The behavioural correlation was produced by both selection by predators and behavioural plasticity. These results support the hypothesis that certain correlations between behaviours might be adaptive in some environments.
Background:
Previous studies have identified abnormalities in brain and motor functioning after concussion that persist well beyond observed clinical recovery. Recent work suggests subtle deficits in ...neurocognition may impair neuromuscular control and thus potentially increase risk of lower extremity musculoskeletal injury after concussion.
Purpose:
To determine the odds of sustaining an acute lower extremity musculoskeletal injury during the 90-day period after return to play from concussion in a cohort of National Collegiate Athletic Association (NCAA) Division I collegiate athletes.
Study Design:
Cohort study; Level of evidence, 3.
Methods:
Included in this study were 87 cases of concussion among 75 athletes (58 men; 17 women) participating in NCAA Division I football, soccer, hockey, softball, basketball, wrestling, or volleyball at a single institution from 2011 to 2014. The 90-day period after return to play for each case of concussion was reviewed for acute noncontact lower extremity musculoskeletal injury. Each 90-day period after return to play was matched to the same 90-day period in up to 3 controls. Control athletes without a history of concussion in the previous year were matched to concussed athletes by sport team/sex, games played, and position. A total of 182 control (136 men; 46 women) 90-day periods were reviewed for acute injury. Conditional logistic regression was used to assess the association between concussion and subsequent risk of acute lower extremity musculoskeletal injury.
Results:
The incidence of acute lower extremity musculoskeletal injury was higher among recently concussed athletes (15/87; 17%) compared with matched controls (17/182; 9%). The odds of sustaining an acute lower extremity musculoskeletal injury during the 90-day period after return to play were 2.48 times higher in concussed athletes than controls during the same 90-day period (odds ratio, 2.48; 95% CI, 1.04-5.91; P = .04).
Conclusion:
Concussed athletes have increased odds of sustaining an acute lower extremity musculoskeletal injury after return to play than their nonconcussed teammates. The study results suggest further investigation of neurocognitive and motor control deficits may be warranted beyond the acute injury phase to decrease risk for subsequent injury.
In this paper I discuss how the challenge hypothesis (Wingfield et al., 1990) influenced the development of ideas about animal personality, and describe particularly promising areas for future study ...at the intersection of these two topics. I argue that the challenge hypothesis influenced the study of animal personality in at least three specific ways. First, the challenge hypothesis drew attention to the ways in which the environment experienced by an organism – including the social environment – can influence biological processes internal to the organism, e.g. changes to physiology, gene expression, neuroendocrine state and epigenetic modifications. That is, the challenge hypothesis illustrated the bidirectional, dynamic relationship between hormones and (social) environments, thereby helping us to understand how behavioral variation among individuals can emerge over time. Because the paper was inspired by data collected on free living animals in natural populations, it drew behavioral ecologists' attention to this phenomenon. Second, the challenge hypothesis highlighted what became a paradigmatic example of a hormonal mechanism for a behavioral spillover, i.e. testosterone's pleiotropic effects on both territorial aggression and parental care causes aggression to “spillover” to influence parenting behavior, thereby limiting behavioral plasticity. Third, the challenge hypothesis contributed to what is now a cottage industry examining individual differences in hormone titres and their relationship with behavioral variation. I argue that one particularly promising future research direction in this area is to consider the active role of behavior and behavioral types in eliciting social interactions, including territorial challenges.
•The challenge hypothesis influenced the study of animal personality.•The challenge hypothesis drew attention to the ways the social environment influences the neuroendocrine system.•The challenge hypothesis provided what became a paradigmatic example of limited plasticity.•The challenge hypothesis stimulated researchers to quantify individual variation in circulating hormone titres.
During the fall of 2020, some high schools across the United States allowed their students to participate in interscholastic sports while others cancelled or postponed their sport programs due to ...concerns regarding COVID-19 transmission. What effect this has had on the physical and mental health of adolescents is unknown.
To identify the effect of playing a sport during the COVID-19 pandemic on the health of student-athletes.
Cross-sectional study.
Sample recruited via email.
A total of 559 Wisconsin high school athletes (age = 15.7 ± 1.2 years, female = 43.6%, male = 56.4%) from 44 high schools completed an online survey in October 2020. A total of 171 (30.6%) athletes played (PLY) a fall sport, while 388 (69.4%) did not play (DNP).
Demographic data included sex, grade, and sport(s) played. Assessments were the General Anxiety Disorder-7 Item for anxiety, Patient Health Questionnaire-9 Item for depression, the Hospital for Special Surgery Pediatric Functional Activity Brief Scale for physical activity, and the Pediatric Quality of Life Inventory 4.0 for quality of life. Univariable comparisons between the 2 groups were made via t tests or χ2 tests. Means for each continuous outcome measure were compared between groups using analysis-of-variance models that controlled for age, sex, teaching method (virtual, hybrid, or in person), and the percentage of students eligible for free or reduced-price lunch.
The PLY group participants were less likely to report moderate to severe symptoms of anxiety (PLY = 6.6%, DNP = 44.1%, P < .001) and depression (PLY = 18.2%, DNP = 40.4%, P < .001). They also demonstrated higher (better) Pediatric Functional Activity Brief Scale scores (PLY = 23.2 95% CI = 22.0, 24.5, DNP = 16.4 95% CI = 15.0, 17.8, P < .001) and higher (better) Pediatric Quality of Life Inventory total scores (PLY = 88.4 95% CI = 85.9, 90.9, DNP = 79.6 95% CI = 76.8, 82.4, P < .001).
Adolescents who played a sport during the COVID-19 pandemic described fewer symptoms of anxiety and depression and had better physical activity and quality-of-life scores compared with adolescent athletes who did not play a sport.
Experiences of parents and/or offspring are often assumed to affect the development of trait values in offspring because they provide information about the external environment. However, it is ...currently unclear how information from parental and offspring experiences might jointly affect the information-states that provide the foundation for the offspring phenotypes observed in empirical studies of developmental plasticity in response to environmental cues. We analyze Bayesian models designed to mimic fully-factorial experimental studies of trans and within- generational plasticity (TWP), in which parents, offspring, both or neither are exposed to cues from predators, to determine how different durations of cue exposure for parents and offspring, the devaluation of information from parents or the degradation of information from parents would affect offspring estimates of environmental states related to risk of predation at the end of such experiments. We show that the effects of different cue durations, the devaluation of information from parents, and the degradation of information from parents on offspring estimates are all expected to vary as a function of interactions with two other key components of information-based models of TWP: parental priors and the relative cue reliability in the different treatments. Our results suggest empiricists should expect to observe considerable variation in the patterns observed in experimental studies of TWP based on simple principles of information-updating, without needing to invoke additional assumptions about costs, tradeoffs, development constraints, the fitness consequences of different trait values, or other factors.
Animals exhibit dramatic immediate behavioral plasticity in response to social interactions, and brief social interactions can shape the future social landscape. However, the molecular mechanisms ...contributing to behavioral plasticity are unclear. Here, we show that the genome dynamically responds to social interactions with multiple waves of transcription associated with distinct molecular functions in the brain of male threespined sticklebacks, a species famous for its behavioral repertoire and evolution. Some biological functions (e.g., hormone activity) peaked soon after a brief territorial challenge and then declined, while others (e.g., immune response) peaked hours afterwards. We identify transcription factors that are predicted to coordinate waves of transcription associated with different components of behavioral plasticity. Next, using H3K27Ac as a marker of chromatin accessibility, we show that a brief territorial intrusion was sufficient to cause rapid and dramatic changes in the epigenome. Finally, we integrate the time course brain gene expression data with a transcriptional regulatory network, and link gene expression to changes in chromatin accessibility. This study reveals rapid and dramatic epigenomic plasticity in response to a brief, highly consequential social interaction.
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