Cholinesterase activity in white-winged doves exposed to methyl parathion.

Captive white-winged doves (Zenaida asiatica) were exposed to various levels of methyl parathion (MP) in drinking water to determine effects on brain and blood cholinesterase (ChE) activity. We conducted two experiments to test the influence of MP dose (the amount of MP actually ingested), MP concentration (the amount of MP per unit water), and exposure duration (number of days exposed to a constant MP concentration) on ChE activity. Plasma ChE activity was not useful in predicting brain ChE activity. Methyl parathion concentration had a greater influence on plasma and brain ChE activity levels than dose or time of exposure. These results contribute to the evaluation of irrigation water as a route of exposure of wildlife to pesticides.

Chlamydiosis in captive white-winged doves (Zenaida asiatica).

Chlamydia psittaci was isolated from the spleen of a moribund white-winged dove (Zenaida asiatica). The isolate was serotyped as the serovar B that is commonly isolated from pigeons. A fourfold increase in the titer of antichlamydial IgM activity occurred in that bird in paired serum samples tested by chlamydial elementary body agglutination (EBA) and a greater than or equal to fourfold decrease of IgG occurred by direct complement fixation (DCF). The increases or decreases of EBA and DCF titers in other clinically ill birds that were treated with tetracycline varied, as normally occurs in cases of avian chlamydiosis. Titers in clinically normal birds were consistent with past infections. These birds were from a captive group of about 200 birds to be used for breeding and reproduction research. A small sample of recently caught wild birds was serologically negative for chlamydial antibody activity.

The evolution of female sexuality and mate selection in humans.

Understanding female sexuality and mate choice is central to evolutionary scenarios of human social systems. Studies of female sexuality conducted by sex researchers in the United States since 1938 indicate that human females in general are concerned with their sexual well-being and are capable of sexual response parallel to that of males. Across cultures in general and in western societies in particular, females engage in extramarital affairs regularly, regardless of punishment by males or social disapproval. Families are usually concerned with marriage arrangements only insofar as those arrangements are economically or politically advantageous, but females most often have a voice in arranged marriages. Extended families also concentrate on a couple's future reproduction rather than on sexual exclusivity. Although marriage for females is often compromised by male or family reproductive interests (which may not in fact differ from female interests), females appear to exercise their sexuality with more freedom than has previously been suggested. Notions of human females as pawns in the male reproductive game, or as traders of sex for male services, should be dispelled.

Forest fragmentation and avian nest predation in forested landscapes.

The size of forest fragments, the use of land bordering fragments, and the distance of nests from an edge all affect the frequency of predation upon bird nests in Maine (USA), an area where the forest has been fragmented by roads, but not significantly reduced in area. We placed artificial nests containing quail eggs in forests of different sizes and at various distances from the edge to test which of these factors was most important in describing predation. Predation was greatest in small tracts surrounded completely by land. Large areas and those bordered on at least one side by a large water body had lower predation rates. This suggests that influx of predators from nearby habitats may be responsible for much of the nest predation in forest fragments.

Mate choice by lineage in three captive groups of rhesus macaques (Macaca mulatta).

The hypothesis that the matrilineal affiliation of 410 infants born in three captive groups of rhesus macaques is independent of the patrilineal affiliation of these infants was tested. Preferential mating with particular patrilines was observed for matrilineal members. We conclude that lineage affiliation does influence mate choice of rhesus macaques, at least when a large number of matrilines and relatively few patrilines which include natal males are represented in the group. Such nonrandom mating might explain high levels of genetic heterogeneity reported among matrilines within rhesus groups, despite high rates of male emigration, and is consistent with the maintenance of high levels of within-matriline kinship which might promote cooperative behavior among matriline members.

Females without infants: mating strategies in two species of captive macaques.

Bonnet (Macaca radiata) and rhesus (Macaca mulatta) macaque females were observed during the breeding season to evaluate differences in mating strategies between females without infants and females with dependent offspring. Rhesus nonmothers participated in consortships earlier in the breeding season and initiated and received more approaches with adult males than rhesus mothers did. Bonnet nonmothers entered estrus earlier, began copulating earlier, and approached and presented to adult males more often than bonnet mothers did. Interacting with males frequently and early in in the breeding season may improve nonmothers' chances of conceiving and bringing offspring to term, with little competition from mother peers.

A comparison of mother and nonmother behaviors during birth season in two species of captive macaques.

9 adult rhesus macaque females (Macaca mulatta) and 7 adult bonnet macaque females (Macaca radiata) were observed during the birth season to identify possible differences between mothers and nonmothers in time budgets and social interactions. Rhesus mothers spent less time moving, feeding, grooming others and aiding others than rhesus nonmothers did. Bonnet mothers spent less time resting and moving, but more time in huddling groups than bonnet nonmothers did. Mothers of both species were approached more than nonmothers, and fed more often near others. The presence of a dependent infant not only alters female time budgets, but also changes social interactions between adult females and other group members.

Selection and the transferrin polymorphism in rhesus monkeys (Macaca mulatta).

Rates of survival, infant growth and fertility of rhesus monkeys with two, one and no C allele(s) at the transferrin locus are compared. Infants with no C allele experience slower growth rates than animals with either one or two C allele(s). While heterozygous females exhibit the highest infant growth rates among females, their fertility is lower and incidence of abortions and stillbirths is higher than for females with two or no C alleles. It is hypothesized that opposing directions of selection at different life-cycle stages maintain a stable equilibrium at the transferrin locus.

Brief repot: Interactions with infants by full siblings, paternal half-siblings, and nonrelatives in a captive group of rhesus macaques (Macaca mulatta).

Six mother-infant pairs in a group of captive rhesus monkeys (Macaca mulatta) were observed for six months. "Infant grabs" by others and mothers' resistance to grabs were scored. More full siblings grabbed infants than either paternal half-siblings or nonrelatives. Mothers resisted grabbing by more nonrelatives than by paternal half-siblings. Although the maternal effect suggested by full sib-infant interactions is expected, the paternal effect revealed by mothers' tolerance of paternal half-sibs, but not full siblings, over nonrelatives is unexpected.