Rank-dependent compromises between growth and predator protection in lizard dominance hierarchies

• Published in: Animal behaviour Vol. 32; no. 4; pp. 1101 - 1107
• Main Author: Stamps, J.A.
• Format: Journal Article
• Language: English
• Published: Kent Elsevier Ltd 01.01.1984; Elsevier
• Subjects: Amphibia and reptilia; Animal ethology; Anolis aeneus; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Psychology. Psychoanalysis. Psychiatry; Vertebrata; Laboratory study; Vertebrata; Social behavior; Sauria; Growth; Defensive behavior; Reptilia; Social organization; Predation; Social hierarchy
• ISSN: 0003-3472; 1095-8282
• DOI: 10.1016/S0003-3472(84)80226-2

Juvenile Anolis aeneus lizards often live in dominance hierarchies, and in both the laboratory and field, rank was primarily determined by a juvenile's size relative to the others when it entered a hierarchy. Because juveniles entered hierarchies soon after hatching and left when they reached subadult sizes, most juveniles slowly rose in status during their sojourn in dominance hierarchies. In laboratory experiments, rank and growth rate were positively related when both food and perches were uniformly distributed. However, when perches were non-uniformly distributed, juveniles competed to live on those perch configurations which offered protection from predators. Under these conditions, growth was more weakly related to rank than in the uniform-habitat trials, and high-ranking juveniles living on the preferred (safe) perches had significantly lower growth rates than those living elsewhere. In contrast, low-ranking juveniles in non-uniform habitats experienced no such compromise between growth and safety, and those on the preferred perches tended to grow faster than those living elsewhere. Since most juveniles in the field seem to gradually rise from low to high rank, the behavioural strategies for optimizing growth and survival may change ontogenetically in this species.