Journal Article

Skeletal age during hurricane impacts fluctuating asymmetry in Cayo Santiago rhesus macaques

Terhune, Claire E., Dickinson, Edwin, Romero, Ashly N., Turcotte, Cassandra M.

2023

Overview

As natural disasters become more frequent due to climate change, understanding the biological impact of these ecological catastrophes on wild populations becomes increasingly pertinent. Fluctuating asymmetry (FA), or random deviations from bilateral symmetry, is reflective of developmental instability and has long been positively associated with increases in environmental stress. This study investigates craniofacial FA in a population of free‐ranging rhesus macaques (Macaca mulatta) that has experienced multiple Category 3 hurricanes since the colony's inception on Cayo Santiago, including 275 individuals from ages 9 months to 31 years (F = 154; M = 121). Using geometric morphometrics to quantify FA and a linear mixed‐effect model for analysis, we found that sex, age, and decade of birth did not influence the amount of FA in the individuals included in the study, but the developmental stage at which individuals experienced these catastrophic events greatly impacted the amount of FA exhibited (p = .001). Individuals that experienced these hurricanes during fetal life exhibited greater FA than any other post‐natal developmental period. These results indicate that natural disasters can be associated with developmental disruption that results in long‐term effects if occurring during the prenatal period, possibly due to increases in maternal stress‐related hormones. Resumen A medida que los desastres naturales se vuelven más frecuentes debido al cambio climático, entender el impacto biológico de estas catástrofes ecológicas en poblaciones silvestres va en aumento pertinente. La asimetría fluctuante (AF), o desviaciones aleatorias de simetría bilateral, es reflejo de inestabilidad durante el desarrollo y se ha asociado positivamente con incrementos en estrés ambiental durante mucho tiempo. Este estudio investiga AF craneofacial en una población de macacos rhesus (Macaca mulatta) en libertad que ha experimentado múltiples huracanes categoría 3 desde el inicio de la colonia en Cayo Santiago, e incluye 275 individuos de 9 meses a 31 años de edad (F = 154; M = 121). Usando morfometría geométrica para cuantificar AF y un modelo lineal de efectos mixtos para análisis, encontramos que el sexo, la edad y la década de nacimiento no influyeron en la cantidad de AF en los individuos incluidos en el estudio, pero la etapa de desarrollo en la que los individuos experimentaron estos eventos catastróficos impactó altamente la cantidad de AF exhibida (p = .001). Los individuos que experimentaron estos huracanes durante el período fetal exhibieron mayor AF que cualquier otro período de desarrollo posnatal. Estos resultados indican que los desastres naturales pueden asociarse con trastornos del desarrollo que tienen efectos a largo plazo si ocurren durante el período prenatal, posiblemente debido al aumento de hormonas maternas relacionadas con el estrés. Fluctuating asymmetry (FA), or random deviations from symmetry, can be used as a proxy for developmental instability, and anthropogenic and natural disruptions have been associated with increased levels of FA. In this study, we investigate the effect of demographic variables (age, sex, and decade of birth) and hurricane experience on FA in a model primate taxon: rhesus macaques (Macaca mulatta) to better understand the impact major ecological catastrophes have on skeletal development. Individuals that experienced a hurricane event in utero exhibited higher levels of FA than juvenile or adult individuals that experienced that same event, which could be due to increased maternal stress hormones such as glucocorticoids that can disrupt fetal development.

• Publisher: John Wiley & Sons, Inc,John Wiley and Sons Inc,Wiley
• Subject: Age / Asymmetry / Catastrophic events / Cayo Santiago / Climate change / Demography / developmental instability / Developmental stages / Ecophysiology / Environmental stress / Females / Fetuses / Fluctuating asymmetry / Functional Ecology / Global Change Ecology / Hormones / hurricane / Hurricanes / Long-term effects / Macaca mulatta / Males / Monkeys & apes / Morphology / Morphometry / natural disaster / Natural disasters / Primates / rhesus macaque / skeletal morphology