Currently, researchers seek to better understand the relationship between the Nazca obligate siblicide practice and NAV behavior practice. The physiological implications of booby’s both aggressive behaviors catalyze questions regarding causation, evolutionary significance, and potential permanent neuroendocrine alterations. Recent research on Nazca booby aggression addresses factors to the physiological understanding of aggression in vertebrate mammals. In vertebrate animals, androgen levels and corticosterone levels regulate aggression. Androgens are sex steroid hormones, including testosterone and progesterone, and corticosterone is a corticoid hormone secreted by the adrenal gland and comprises the primary avian stress response (Nelson 2006). Understanding the role of hormones and the adaptive significance of the aggressive behavior of the Nazca booby is a growing field of research Hypotheses In this research, two hypotheses focusing on siblicide and NAV behavior will be pursued. They are: 1. Lethal aggression levels in Nazca boobies are beneficial during the neonatal stage because they enable brood reduction. 2. Aggression becomes maladaptive in adulthood because it catalyzes a cycle of harmful adult visitor interactions (NAV). Each hypothesis will be evaluated through reading and analysis of existing literature. Findings Hypothesis 1: To address the first hypothesis, the significance of brood reduction through obligate siblicide must be established. Research demonstrates that the optimal brood size for the Nazca booby is one. A single chick is more likely to pass on its genes to future generations in
Currently, researchers seek to better understand the relationship between the Nazca booby’s obligate siblicide practice and NAV behavior practice. The physiological implications of both aggressive behaviors catalyze questions regarding causation, evolutionary significance, and potential permanent neuroendocrine alterations. Recent research on Nazca booby aggression addresses factors to the physiological understanding of aggression in vertebrate mammals. In vertebrate animals, androgen levels and corticosterone levels regulate aggression. Androgens are sex steroid hormones, including testosterone and progesterone, and corticosterone is a corticoid hormone secreted by the adrenal gland and comprises the primary avian stress response (Nelson 2006). Understanding the role of hormones and the adaptive significance of the aggressive behavior of the Nazca booby is a growing field of research Hypotheses In this research, two hypotheses focusing on siblicide and NAV behavior will be pursued. They are: 1. Lethal aggression levels in Nazca boobies are beneficial during the neonatal stage because they enable brood reduction. 2. Aggression becomes maladaptive in adulthood because it catalyzes a cycle of harmful adult visitor interactions (NAV). Each hypothesis will be evaluated through reading and analysis of existing literature. Findings Hypothesis 1: To address the first hypothesis, the significance of brood reduction through obligate siblicide must be established. Research demonstrates that the optimal brood size for the Nazca booby is one. A single chick is more likely to pass on its genes to future generations in
final_nazca_booby_paper.docx