Geographic variation was analysed in morphological (colour, morphometric) and genetic (electrophoretic, chromosomal) characters in the yellow mongoose cynictis penicillata, a diurnal, colonial, burrow-dwelling viverrid, endemic to and widespread throughout Southern Africa. The causal bases of observed geographic patterns were investigated, and a taxonomic revision of the species was undertaken. Three physical properties of pelage colour (hue, value and chroma) were measured independently using Munsell colour charts and a tristimulus colorimeter. Hue and chroma varied from yellowish (hue) and bleached (chroma) in the north to a brighter, (chroma) tawny-orange (hue) in the south. A zone of rapid colour change separated northern and southern groups. Specimens from the drier western areas were paler (in value) than specimens from more easterly localities. Colour patterns were interpreted in terms in the principle of metachromism. Environmental correlates of colour were analysed. Non-geographic (age, sex, individual) and geographic variation was analysed in 14 cranial and two external characters, using multivariate and univariate techniques. The species does not show secondary sexual dimorphism. Multivariate analyses resulted in the description of four parapatric subspecies, three of which were distinguished on the basis of skull size (which accounted for 93% of geographic variation). Subspecies were separated by continuous zones of craniometric differentiation (transition zones). Craniometric overlap (intergradation) occurred across transition zones. The geographic pattern of craniometric variation in C. penicillata could be explained by either an allopatric or a parapatric mode of speciation. A cladistic analysis of coded cranial characters was used to infer the historical pattern of range expansion in the species. The population genetical structure, based on electrophoretic analysis of 28 loci in eight populations of yellow mongooses, was characterised by the absence of genetic divergence between morphometrically-defined subspecies, a mean expected heterozygosity of 3.4%, low genetic distances between populations (0.000--0.105 for Nei's genetic distance), and a surprisingly high fixation index (FST) of 0.585. The basic karyotype of the yellow mongoose was invariant geographically (2n = 36, NF = 72), although a single, supernumerary microchromosome was detected in four out of the five populations sampled. G- and C-banded karyotypes are presented. Evolutionary relationships among eight Southern African viverrid species, including the yellow mongoose, were inferred from phenetic and cladistic analyses of allelic variation at 18 protein loci. These data suggested the separate evolution of social and solitary lineages of mongooses. / Thesis (Ph.D.)-University of Natal, 1990.

Dissertation (PhD)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Thesis (PhD (Botany and Zoology))--University of Stellenbosch, 2007. / Improved anti-predator protection has been postulated to be the primary advantage of sociality in the family Herpestidae. Therefore, the yellow mongoose, Cynictis penicillata, is considered an anomaly in the family because it may den socially with conspecifics, cooperating in the rearing of young and territory defence, but inevitably forages alone. I studied the communicative and anti-predator behaviour of a population of yellow mongooses which exhibited a lower degree of sociality than populations studied elsewhere. The yellow mongoose’s flexible social nature was evident in its vocal repertoire. Although its vocal repertoire was smaller and less context-specific than those of social mongooses, it had a large proportion (over 50%) of affiliative vocalizations, suggesting that individuals show a higher degree of cooperation than strictly solitary species. During predator encounters yellow mongooses used a simple urgency-based alarm call repertoire, indicating high and low urgency threat with two separate call types. The social environment strongly affected the alarm communication of yellow mongooses – vocal alarms were displayed almost exclusively by individuals in a group, whereas the visual alarm (a raised tail) was displayed by solitary individuals, when predators were outside the range from which they were potentially dangerous. This was a clear demonstration of the ‘audience effect’ – a phenomenon whereby animals adjust their communicative signals depending on the audience that is present. Until this study, the audience effect has only been demonstrated in obligate social species. The yellow mongoose’s social flexibility was further reflected in its territorial scent marking behaviour. In contrast to high density populations, where subordinate individuals contribute significantly to territory defence and scent marking, only the dominant male marked and defended territory borders in this low density population. Dominant males appeared to overmark the small number of cheek marks that females deposited, especially during the breeding season, which suggests that cheek marks were used in mate guarding. The yellow mongoose showed less flexibility in responses to conspecifics while foraging: the presence of group members appeared to make foragers more nervous, as individuals increased vigilance and decreased foraging success when group members were nearby. This could not be attributed to foraging competition, which happened very rarely. Yellow mongooses relied on a form of vigilance that allowed them to continue foraging while remaining alert, which contrasted with meerkats, Suricata suricatta, that had to interrupt foraging in order to be vigilant. The foraging patterns of yellow mongooses and meerkats differed markedly, and both species appeared to be inflexible in these patterns. I have proposed, therefore, that rigid vigilance patterns of vigilance are the reason why yellow mongooses forage alone, despite showing other cooperative tendencies. This study highlights that the selective forces acting on group living and group foraging are very different, and that the group-size effect – which postulates that individual vigilance declines as group size increases – may not be applicable to species adapted to solitary foraging.

Very little is known about the spatio-temporal ecology of the yellow mongoose Cynictis penicillata, despite this small carnivore being widely distributed in the southern African subregion. Until the present study, activity patterns and daily movement distances had only been investigated over a single season, and information on home range sizes was only available from a few populations. Here, I aimed at determining the activity patterns and the space use of yellow mongooses over the different seasons of the year in the Great Fish River Reserve (Eastern Cape, South Africa). In addition, I tested some predictions related to environmental factors (variations in photoperiod, climatic conditions and food availability over the year), as well as life cycle (reproduction) and morphological and physiological characteristics (sexual dimorphism and thermoregulatory aspects associated to the possession of an elongated body). From September 2005 to August 2011, spatio-temporal data were collected through 102 continuous tracking sessions (84 during the day and 18 during the night) of 12 adult individuals (seven males and five females) fitted with motion-sensor radio-collars. Additional data were obtained through semi-continuous tracking sessions and random locations. Yellow mongooses were essentially diurnal and crepuscular. Activity levels averaged 57 percent during the day (n = 11,807 fixes) and only 11 percent at night (n = 3,623 fixes). Yellow mongooses emerged from their burrows on average (± SD) 85 ± 62 min after sunrise (range: –11 to +369 min) and returned 21 ± 84 min before sunset (range: –518 to +225 min). The duration of the daily activity period varied between 12 min and 15 h 36 min, with a mean of 9 h 28 min. Both sexes exhibited some overground activity after sunset, but this was most pronounced in males than in females. Nocturnal activity outside the activity period was generally restricted to short underground bouts of activity occurring at anytime of the night. Diurnal resting, with up to 11 bouts per activity period, occurred in 98.8 percent of activity periods. Overall, yellow mongooses were active during 68 ± 17 percent of the time spent outside the burrow. Photoperiod acted as a zeitgeber and activity was negatively affected by adverse climatic conditions (very hot or conversely low temperatures, rain, wet soil) and probably low terrestrial arthropod activity/availability. No intersexual difference in activity levels was found, although the higher body mass of males (on average 16 oercent) implies higher metabolic demands. The total home range size (MCP 100 percent ) averaged 0.55 ± 0.65 km2 (range: 0.10–2.36 km2) and the related total perimeter measured on average 2.80 ± 1.71 km (range: 1.17–7.36 km). Male home ranges were on average more than twice large than those of females, but this difference did not reach statistical significance. However, males had larger daily home ranges (0.13 ± 0.15 km2) than females (0.05 ± 0.05 km2). In addition, daily movement distances of males were longer (1.99 ± 1.07 km) than those of females (1.29 ± 0.66 km). Males also travelled at a faster speed (0.29 ± 0.13 km/h) than females (0.18 ± 0.07 km/h). Overall, sex clearly appeared to play a role in the spatial ecology of yellow mongooses, but the underlying explanation does not seem to be linked to sexual dimorphism (body mass) or reproductive activity. Whilst the role of food availability on the space use of yellow mongooses is unclear, it is likely that low temperatures negatively affect yellow mongoose movements, as they do for their activity levels.