Postural behavior during sleep in wild howler monkeys (Alouatta palliata, A. macconnelli, and A. caraya): an Assessment across the genus range

URBANI, BERNARDO; YOULATOS, DIONISIOS; KOWALEWSKI, M MARTIN

Curitiba

Congreso; XIV Congresso Brasileiro de Primatologia; 2011

Sociedad Brasileira de Primatologia

Sleep is the longest and more continuous behavioral phase in the diel cycle of mammals.However, selection of postures, substrates, and tree parts during sleep has not been adequately explored, as well as their ultimate evolutionary consequences. The present study investigates postural behavior,  Substrate and tree part use during sleep in three howler species (A. palliata, A. macconnelli, and A. caraya) in Nicaragua, French Guyana, and Argentina, respectively. All three species were consistent in the use of a crouched ball-like sit-in posture, on large, horizontal, single or with bifurcation substrates, and avoiding the periphery of the tree crowns. The regularity of these patterns are very likely functionally associated with protection from potential predators and extreme weather conditions, biomechanical stability, thermoregulation, and, most likely enhancement of the digestive process of hard to decompose plant material in association with extended sleeping periods. Further similar studies on other howler species, as well as other atelines and the highly folivorous colobines will help elucidate these functional relationships throughout the primate radiations. A. palliata, A. macconnelli, and A. caraya) in Nicaragua, French Guyana, and Argentina, respectively. All three species were consistent in the use of a crouched ball-like sit-in posture, on large, horizontal, single or with bifurcation substrates, and avoiding the periphery of the tree crowns. The regularity of these patterns are very likely functionally associated with protection from potential predators and extreme weather conditions, biomechanical stability, thermoregulation, and, most likely enhancement of the digestive process of hard to decompose plant material in association with extended sleeping periods.  Further similar studies on other howler species, as well as other atelines and the highly folivorous colobines will help elucidate these functional relationships throughout the primate radiations.A. palliata, A. macconnelli, and A. caraya) in Nicaragua, French Guyana, and Argentina, respectively. All three species were consistent in the use of a crouched ball-like sit-in posture, on large, horizontal, single or with bifurcation substrates, and avoiding the periphery of the tree crowns. The regularity of these patterns are very likely functionally associated with protection from potential predators and extreme weather conditions, biomechanical stability, thermoregulation, and, most likely enhancement of the digestive process of hard to decompose plant material in association with extended sleeping periods.  Further similar studies on other howler species, as well as other atelines and the highly folivorous colobines will help elucidate these functional relationships throughout the primate radiations.