Acute and chronic stress increase DHEAS concentrations in rhesus monkeys.

Most studies on the stress-responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis have focused on glucocorticoids, while few studies have investigated the adrenal secretion of dehydroepiandrosterone sulfate (DHEAS), which is unique to primates. Monkeys were chair-restrained for 2h per day for seven consecutive days, and blood samples were collected upon placement in the chair, and at 15, 30, 60 and 120 min later. Like cortisol, DHEAS concentrations increased throughout the initial session of chair restraint (acute stress).

Overview: Expanding an animal's self-world to include conspecifics.

To further the thinking about animal communication, the authors have returned to J. von Uexküll's (1934/1957) original writings on the Umwelt. Applying J.