Abstract: INTRODUCTION Thinking about Animals For nearly as long as anything can be inferred about human cognition, paleoanthropologists and archaeologists believe humans have thought carefully about animals, about the “predominant characteristic” of each animal, and about those “contradictory elements” that make up humankind. This careful thought has had many outcomes, some scientific, others not. Among the scientific outcomes in the 19th century was evolutionary thinking about the causes and consequences of domestication, including Charles Darwin's study (32) of the mechanics of human (artificial) selection of domesticated animal and plant population characteristics. In the 20th century, theoretical refinements and the painstaking collection of empirical data have led to studies of such disparate phenomena as the physical consequences of keeping pets (12); the spread of antibiotic-resistant bacteria as a result of feeding antibiotics to livestock (117); and the evolutionary consequences of milkdrinking (99). Speculation about the origins of human-animal interaction is not the exclusive province of scientists: religions and storytellers alike customarily try to account for the beginnings of human-animal interaction. Genesis does so

Abstract: Nursing behaviour and related aggression of mare-foal pairs was studied from birth (n = 21) to 24 weeks of age (n = 15) of the foal. Foals exhibited a decreasing length and frequency of nursing as they grew older. Mares rarely aggressed against their foals during nursing in the foal's first 4 weeks of life, but did so increasingly through Weeks 13-16, after which the rate of aggression during nursing decreased. Mares terminated nursing primarily by moving away, and were most likely to do so during the foal's first 4 weeks of life. They became gradually less likely to do so as the foal grew older. It was concluded that mares sometimes flex their hind limb on the side opposite the foal during nursing in order to conserve energy in a situation in which they would be remaining still anyway. There was no difference between colts and fillies in the frequency or duration of nursing or in the frequency with which their mothers aggressed against them or terminated nursing.

Abstract: Pigeons were exposed to autoshaping procedures under which 50% of red key illuminations were followed by 9-sec food deliveries, and 50% of blue key illuminations were followed by 3-sec food deliveries. When all key illuminations were 6 sec, pigeons preferred the red stimulus. Subsequent manipulations demonstrated that preference could be shifted to the blue stimulus by either increasing the duration of the red stimulus or imposing a delay interval between the offset of that stimulus and food delivery. A final experiment demonstrated that, in two of three subjects, preference for key illuminations associated with longer, but delayed, food deliveries generally increased as the duration of all key illuminations was lengthened. These results, obtained under conditions where keypecking had no programmed consequences, are similar to those previously observed under procedures involving a positive response-food dependency.

Abstract: In colts and fillies observed from birth to 24 weeks old, coprophagy occurred from Weeks 1 to 19. Its frequency was greatest during the first two months. Coprophagy was rarely observed in mares and stallions. Foals usually ate the faeces of their mother but were observed to eat their own and those of a stallion and another unrelated mare. Urination by the foal occurred before, during or after 26 per cent of the coprophagy incidents. It is hypothesised that foals may consume faeces in response to a maternal pheromone which signals the presence of deoxycholic acid or other acids which the foal may be deficient in and which it may require for gut immuno-competence myelination of the nervous system. Such a pheromone may also serve to accelerate growth and sexual maturation. Coprophagy may also provide nutrients and introduce normal bacterial flora to the gut.