Living in nonbreeding groups: an alternative strategy for maturing gorillas.

The one-male reproductive strategy implies that maturing males are temporarily excluded from reproduction. In gorillas, these excluded males live either solitarily or in nonbreeding groups (NBGs) that are devoid of adult females. The dynamics of NBGs are not well known.

Ancient co-speciation of simian foamy viruses and primates.

Although parasite-host co-speciation is a long-held hypothesis, convincing evidence for long-term co-speciation remains elusive, largely because of small numbers of hosts and parasites studied and uncertainty over rates of evolutionary change. Co-speciation is especially rare in RNA viruses, in which cross-species transfer is the dominant mode of evolution. Simian foamy viruses (SFVs) are ubiquitous, non-pathogenic retroviruses that infect all primates.

Population and group structure of western lowland gorillas (Gorilla gorilla gorilla) at Lokoué, Republic of Congo.

During a 17-month study at the Lokoué clearing in Odzala National Park, Republic of Congo, we identified 377 western lowland gorillas. This population included 31 solitary males, 37 breeding groups, and eight nonbreeding groups. Its age- and sex-class structure was similar to those observed at two other clearings in the same forest block.

Screening for simian foamy virus infection by using a combined antigen Western blot assay: evidence for a wide distribution among Old World primates and identification of four new divergent viruses.

Simian foamy viruses (SFVs) belong to a genetically and antigenically diverse class of retroviruses that naturally infect a wide range of nonhuman primates (NHPs) and can also be transmitted to humans occupationally exposed to NHPs. Current serologic detection of SFV infection requires separate Western blot (WB) testing by using two different SFV antigens [SFV(AGM) (African green monkey) and SFV(CPZ) (chimpanzee)]. However, this method is labor intensive and validation is limited to only small numbers of NHPs.

Mineral content as a basis for food selection by western lowland gorillas in a forest clearing.

The forests in northwest Republic of Congo contain a number of herbaceous swamp clearings that provide foraging sites for lowland gorillas (G.g. gorilla).

Testing the reliability of noninvasive genetic sampling by comparing analyses of blood and fecal samples in Barbary macaques (Macaca sylvanus).

Genetic studies of wild animal populations are often hindered by difficulties in obtaining blood samples. Recent advances in molecular biology have allowed the use of noninvasive samples as sources of DNA (e.g.

Is male-infant caretaking related to paternity and/or mating activities in wild Barbary macaques (Macaca sylvanus)?

In species with a promiscuous mating system, the functions of male-infant caretaking remain unclear in the absence of genetic paternity tests. We tested paternal investment and hypotheses concerning reproductive tactics in wild groups of Barbary macaques, including results of genetic paternity tests. Our study revealed that male-infant caretaking was not related to the probability of paternity.

Identification of Ebola virus sequences present as RNA or DNA in organs of terrestrial small mammals of the Central African Republic.

The life cycle of the Ebola (EBO) virus remains enigmatic. We tested for EBO virus in the organs of 242 small mammals captured during ecological studies in the Central African Republic. EBO virus glycoprotein or polymerase gene sequences were detected by reverse transcription PCR in RNA extracts of the organs of seven animals and by PCR in DNA extract of one animal.

Simian immunodeficiency virus (SIV) from sun-tailed monkeys (Cercopithecus solatus): evidence for host-dependent evolution of SIV within the C. lhoesti superspecies.

Recently we reported the characterization of simian immunodeficiency virus (SIVlhoest) from a central African l'hoest monkey (Cercopithecus lhoesti lhoesti) that revealed a distant relationship to SIV isolated from a mandrill (SIVmnd). The present report describes a novel SIV (SIVsun) isolated from a healthy, wild-caught sun-tailed monkey (Cercopithecus lhoesti solatus), another member of the l'hoest superspecies. SIVsun replicated in a variety of human T-cell lines and in peripheral blood mononuclear cells of macaques (Macaca spp.

Population structure and group composition of western lowland gorillas in north-western Republic of Congo.

Population studies are an essential part of conservation actions. Under exceptional observation conditions we studied a western lowland gorilla population visiting the Maya salt-clearing (north of the Parc national d'Odzala, P.N.

Fruit characters as a basis of fruit choice and seed dispersal in a tropical forest vertebrate community.

Interactions between a large community of vertebrate frugivore-granivores (including 7 species of large canopy birds, 19 species of rodents, 7 species of ruminants, and 6 species of monkeys), and 122 fruit species they consume, were studied for a year in a tropical rainforest in Gabon.The results show how morphological characters of fruits are involved in the choice and partitioning of the available fruit spectrum among consumer taxa. Despite an outstanding lack of specificity between fruit and consumer species, consideration of simple morphological traits of fruits reveals broad character syndromes associated with different consumer taxa.

[Demography and reproduction of Macaca sylvanus in different habitats in Algeria].

Usually described as a cedar forest monkey, the Barbary macaque in effect has colonized a great variety of habitat types. At the moment, it is not known to what extent these different habitats are suitable for the species' survival. We tried to answer this question by comparing the demography of three monkey troops: one lives in a deciduous oak forest; the second lives in an nondeciduous cedar-green oak forest while the third is found on rocky ridges of mountains without any arborescent vegetation.

[Vocal behavior of adult males and superspecific organization in polyspecific troops of monkeys].

Analysis of the vocal behaviour of adult males from different species of Cercopithecus monkeys in a polyspecific troop shows important species differences, which suggest a superspecific organization upon which the extraordinary stability of certain polyspecific associations can depend. In the community studied, the male Cercopithecus pogonias generally controlled the formation and disbanding of polyspecific troops, coordinated their movements and the spacing between troops, while Cercopithecus cephus seemed to be the 'follower' species. However, the roles were divided for defence against predators: male C.

A comparison of the diets of three major groups of primary consumers of Gabon (primates, squirrels and ruminants).

The diets of three major groups of frugivores-folivores of an African rain forest (squirrels, ruminants, primates) are compared and the relationship of food habits to body weight, habitat and foraging height examined. A number of common trends in the trophic patterns are found in the three groups. Over half of the fruit species identified in the diets of any one taxon are exploited in common with one or more of the others.

[Growth, sexual maturity, social maturity and reproduction in African Forest Cercopithecines (author's transl)].

The onset of puberty in males is indicated by a strong increase of weight, appearance of specific displays and changes in the vocal repertoire. Male social maturity follows sexual maturity, but does not depend only on age; it results also from behavioural interactions with the male leader within the one-male group.