This report describes a reactive mesothelial hyperplasia as a reaction to a polyserositis in an African green monkey (Chlorocebus aethiops) mimicking an epitheloid mesothelioma. Histopathology, immunohistochemistry, fluorescence in situ hybridization, and electron microscopy were used to determine the benign nature of the mesothelial proliferation. For the first time, human genetic probes had been successfully applied to an African green monkey.

This report describes a case of unintended importation of tropical baby jumping spiders to a laboratory monkey colony. The spiders were detected in a cocoon attached to a banana for monkey consumption. In identifying the family of spiders as jumping spiders (Salticidae), it turned out that these spiders would not have been venomous to humans and they most likely would not have had the potential to establish a new spider colony in the facility.

In order to contribute to the discussion on the presence of a grooming claw in New World monkeys, we examined living animals, museum specimens and photos of saki monkeys, genus Pithecia. We found that some individuals may possess a grooming claw or at least a grooming claw-like nail on the second toe, while others do not.

Sleep is the longest and most continuous behavioral phase in the 24 h cycle of mammals. However, selection of postures, substrates, and tree parts during sleep has not been adequately explored, as well as their 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 Guiana, and Argentina. All three species were consistent in the use of a crouch.

Great apes and humans can develop similar health conditions, including heart disease. As lipids predict health risk in humans, we explored whether they do so in gorillas and also examined relationships with age and sex. Multiple sex and age differences were observed. Age, sex, and lower LDL / HDL ratio best predicted morbidity risk, which may be related to arthritis. Unlike humans, in gorillas age and sex alone best predicted cardiac disease, and mortality risk was best predicted only by age.