Analysis of hair cortisol levels in captive chimpanzees: Effect of various methods on cortisol stability and variability

Hair cortisol has been reported to be a useful measure of long-term hypothalamic-pituitary-adrenal (HPA) axis activation in several species. It serves as a practical tool for long-term stress assessment, but it is important to understand the methodological factors that can affects hair cortisol assays to avoid methodological artifacts. To that end, we tested several procedures for measuring cortisol levels in hair collected from captive chimpanzees. The results showed that reproducibility was high, and we found no differences in cortisol levels among the various storage, drying, and sampling methods. However, the fineness of homogenized hair, sample weight, and extraction time affected absolute hair cortisol concentration. Although hair cortisol levels were stable over time, factors that may influence measurement results should be kept constant throughout a study.We modified and validated a methodology involving enzyme immunoassays to reliably measure the hair cortisol levels of captive chimpanzees.The results revealed that the fineness of homogenized hair, sample weight, and extraction time caused variations in absolute hair cortisol concentrations in chimpanzees. In contrast, storage, drying, and sampling from similar body parts did not affect the results

A Preliminary Report on Distribution of the Tschego Chimoanzee (Pan t. troglodytes) in the Region of Lekoumou, Republic of Congo

An extensive survey of tschego chimpanzees (Pan troglodytes troglodytes) was carried out in the south-western Congo from January to March, 1992. The survey was conducted by inquiries at 12 villages and by searching in the forests around 6 villages. The local people confirmed the presence of chimpanzees in all villages. Four parties of chimpanzee were observed directly in the forests around 4 villages, and 100 nests were recorded. Chimpanzee population density was low because of hunting and logging pressures in most of the areas. Higher population density was formed in an area without hunting. This area may be an acceptable location for a new research site if suitable measures for chimpanzee conservation are implemented as soon as possible

Origin of the human family

There are more than 300 species of primates, including human beings, on earth. Human beings share various characteristics such as morphology, physiology, ethology, and sociology with other primates. Primates have a common ancestor, and so a common evolutionary history. Various social units formed in primate societies exhibit a range of behaviors including monogamy, polygyny, polyandry, and multi-male/multi-female relations. Among all primates, however, only humans have a social “family” unit. The family is defined as a small-scale kin group consisting of a husband, a wife, and a child. This is the smallest social unit in human society, and it is found in almost all human societies. How would this social unit, unique to humans, have been formed? Johanson and White (1976) discovered the fossilized remains of Australopithecus afarensis, the Hominidae, who lived 3.75 million years ago, in Hadar, Ethiopia. These fossils were found to be a lineal ancestor to the human race, and were named the “first family, ” because the fossils of 13 individuals (both sexes, including children) were excavated from the same ruins. However, the first family's behaviors and societies were not fossilized. Development of the family unit was a dynamic process, and therefore it is only speculation that human evolution resulted from a group of close relatives who had in turn evolved from a common ancestor. Imanishi (1951) identified four conditions necessary to a human family as being: 1. a taboo against incest, 2. exogamy, 3. community, and 4. the division of labor. I would like to discuss the origins of human society by comparing our closest relatives, the society of apes, to the four conditions Imanishi described as necessary to a human family

Comparison of proximity and social behaviors between calves and juveniles in wild giraffe

March 16-17, 2016To date, no study has quantitatively compared the proximity or social interactions between calves and other giraffes except their mothers. In this study, we compared proximity and social behaviors between calves and juveniles to understand developmental changes in giraffe. We observed giraffe in Katavi National Park, Tanzania. We recorded the herd size, the age-sex classes (calf, juveniles, adult female and adult male) of all herd members and proximity conditions. Additionally, we recorded the occurrence, the age-sex class of other individual and direction of muzzling, necking and anogenital examination. Calves showed the lowest rate in proximity with adult males and the highest rate in proximity with same-aged peer. Juveniles spent less time with same-aged peers probably because they are joining herds containing multiple adults. Juvenile can travel for long distances so they have more chances to encounter other age-sex individuals and stay in proximity to them. Calves also received muzzle from many other age-sex classes frequently, whereas juveniles did not receive it frequently. We suggest that the differences between calves and juveniles in proximity duration and social behavior reflects a developmental pathway associated with differences in predator risk, and well as age-related influences on establishing social networks and learning social skills

MAMMALIAN FAUNA OF THE MIOMBO FOREST IN THE UGALLA AREA, WESTERN TANZANIA

We collected basic data on the mammalian fauna of the Ugalla area (05°13.0'S, 30°27.5'E), western Tanzania. We identified 50 mammalian species: seven species of Primates; at least one unidentified species of Chiroptera; two identified species of Lagomorpha; four identified species of Rodentia; 17 identified and at least two unidentified species of Carnivora; one species of Tubulidentata; one species of Hyracoidea; and 15 species of Artiodactyla. Nineteen of these species had not previously been reported from Ugalla. Moreover, eight of these mammal species had not previously been confirmed in this area, according to the Red List of the International World Conservation Union. Ugalla has a diverse mammalian fauna, including species that originated in the tropical rainforest and acacia savanna. In addition, our surveys suggest that genets, African civets, leopards, bush hyraxes and southern reedbucks have different ecologies from mammals in other regions