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While melanistic genets (Genetta spp.) are well known in a few species of the genus, albino specimens have not been described to date. Here, we report on the presence of unusual albino and melanistic common genets (Genetta genetta) in Spain, discussing their frequency of occurrence in the wild. Melanistic and albino common genets are not known in the original African range of the species, thus phenotypical variability in coat colour appears to be greater in Europe, its introduced range. Natural (e.g. a reduced risk of predation in Europe) and/or artificial (e.g. captive-rearing of the species) selection could explain this fact, but more research on the topic is needed.
The seasonal home range size and spatial relationships of 16 adult genetsGenetta genetta Linnaeus, 1758 (6 males and 10 females) were estimated in a Mediterranean habitat of northeastern Spain. Genets minimum density was estimated as 0.98/km2. Mean annual home range was 113.1 ha in males and of 72.0 ha in females. Males had larger home ranges than females in all seasons, but differences were only significant in winter. Home range size changed seasonally and showed a similar pattern in both sexes, with lower values in summer (males — 41.2 ha, females — 29.0 ha) and maximum ones in spring (males — 78.8 ha, females — 56.1 ha). Animals displayed spatial fidelity throughout the year. Core areas (MCP50) represented 27% and 19% of total home range size for males and females, respectively. Resting home ranges (based on locations of inactive animals) were 9 times lower than overall home range size. Individuals of the same sex overlapped less than individuals of different sexes, especially with regard to core areas, which showed almost no overlap. The results obtained suggest that (1) different factors are likely to affect the space use of genets, such as body mass, food abundance and reproductive cycle; (2) genets use space in a heterogeneous way, with areas of greater activity than others within their home range; (3) there was intrasexual segregation with regard to space use.
Genet Genetta genetta Linnaeus, 1758 habitat selection was studied through midden locations in a mountain area of central Spain both at macrohabitat (habitat types, land use, roughness, distance to villages, etc) and microhabitat scale (tree, scrub, rock and pasture covers). Among the available habitats, genet preferred dehesas, due to their good trophic resources and shelter availability. Genet was scarce over 1200 metres, probably because of thermic restrictions. The most important microhabitat variables selected as faecal sites were rock-cover (refuges) and shrub­-cover (feeding places and refuges). Other parameters of functional significance related to midden location were social communication and territoriality. There was no selection both sites with a high degree of tree cover (microhabitat) and for sites near to watercourses.
The processes determining the formation and structure of grassland community are realised at threee levels: the genetic individual (genet, clone), the population and the community. Clonal plants are the dominant species in a grassland community. Clonal growth, modular structure of the plants, as weil morphological and physiological properties and adaptations such as: modification of shoots to form stolons and rhizomes, morphological and physiological integration of modules (ramets), disintegration of the clone and independence of rooted ramets, and growth and death of ramets in the life cycle of clonal plants, inlfuence the life span of the genet, the way of the clone's spreading and the position in the community. The above traits have a significant influence on the regeneration of plants after mowing and grazing, as weil as on the resistance to environmental disturbances. The possibility of increased population abundance through generative and vegetative reproduction is a characteristic trait of clonal plants. Clonal growth of plants, the pattern of spatial formation of the clone, interactions and reciprocal compromises between the species in the neighbourhood have a significant influence on the coexistence of various species in a grassland community. Clonal plants are adapted to mowing and grazing. The abandonment of seminatural grassland causes unfavourable changes to the community structure and its species composition.
We present herein new data on karyotypes of members of the genusGenetta. G- and C-banded chromosomes of the Johnston’s genetGenetta johnstoni Pocock, 1908 (2n = 50 / FNa = 92) are described for the first time, and compared with those ofG. genetta (2n = 54 / FNa = 92). In addition, the standard karyotype ofG. maculata (2n = 52 / FNa = 96) was studied. A reassessment of taxonomic attribution of previously published material allowed us to characterize (2n, FNa, and chromosome morphology) the karyotypes of three genets, previously unknown (G. pardina, G. letabae andG. tigrina). Our results show that despite a rather low interspecific variability in 2n and FNa, all the species of genets (exceptG. pardina andG. maculata) appear differentiated when chromosomal morphology is taken into account. Although chromosomal banding data are limited, confrontation of G-band karyotypes with preliminary molecular phylogenetic results reveals that karyotypic evolution within the genusGenetta might involve various rearrangements like Robertsonian and tandem translocations, pericentric inversions, and centromere fissions; thus providing at least for some taxa a solid postzygotic isolation. Finally, our study suggests that cytogenetic analyses might constitute a useful tool for questioning interspecific boundaries, especially within the taxonomically debated complex of large-spotted genets.
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