9 research outputs found
The impact of fire on habitat use by the short-snouted elephant shrew ('Elephantulus brachyrhynchus') in North West Province, South Africa
Several studies have investigated the response of small mammal populations to fire, but few have investigated behavioural responses to habitat modification. In this study we investigated the impact of fire on home range, habitat use and activity patterns of the short-snouted elephant shrew (Elephantulus brachyrhynchus) by radio-tracking individuals before and after a fire event. All animals survived the passage of fire in termite mound refugia. Before the fire, grassland was used more than thickets, but habitat utilization shifted to thickets after fire had removed the grass cover. Thickets were an important refuge both pre- and post-fire, but the proportion of thicket within the home range was greater post-fire. We conclude that fire-induced habitat modification resulted in a restriction of E. brachyrhynchus movements to patches of unburned vegetation. This may be a behavioural response to an increase in predation pressure associated with a reduction in cover, rather than a lack of food. This study highlights the importance of considering the landscape mosaic in fire management and allowing sufficient island patches to remain post-fire ensures the persistence of the small mammal fauna
Where are you from, stranger? The enigmatic biogeography of North African pond turtles (Emys orbicularis) .
Abstract The European pond turtle (Emys orbicularis) is a
Nearctic element in the African fauna and thought to have
invaded North Africa from the Iberian Peninsula. All North
African populations are currently identified with the subspecies
E. o. occidentalis. However, a nearly range-wide sampling in
North Africa used for analyses of mitochondrial and microsatellite
DNA provides evidence that only Moroccan populations
belong to this taxon, while eastern Algerian and Tunisian pond
turtles represent an undescribed distinct subspecies. These two
taxa are most closely related to E. o. galloitalica with a native
distribution along the Mediterranean coast of northern Spain
through southern France to western and southern Italy. This
group is sister to a clade comprising several mitochondrial lineages
and subspecies of E. orbicularis from Central and Eastern
Europe plus Asia, and the successive sisters are E. o. hellenica
and E. trinacris. Our results suggest that E. orbicularis has been
present in North Africa longer than on the Iberian Peninsula and
that after an initial invasion of North Africa by pond turtles from
an unknown European source region, there was a phase of
diversification in North Africa, followed by a later re-invasion
of Europe by one of the African lineages. The differentiation of
pond turtles in North Africa parallels a general phylogeographic
paradigm in amphibians and reptiles, with deeply divergent
lineages in the western and eastern Maghreb. Acknowledging
their genetic similarity, we propose to synonymize the previously
recognized Iberian subspecies E. o. fritzjuergenobsti with E. o.
occidentalis sensu stricto. The seriously imperiled Moroccan
populations of E. o. occidentalis represent two Management
Units different in mitochondrial haplotypes and microsatellite
markers. The conservation status of eastern Algerian pond turtles
is unclear, while Tunisian populations are endangered.
Considering that Algerian and Tunisian pond turtles represent
an endemic taxon, their situation throughout the historical range
should be surveyed to establish a basis for conservation
measures
Standard karyotypes of two populations of the <em>Scincus scincus</em> complex from Tunisia and Morocco (Reptilia: Scincidae)
A study on chromosomes of two Scincus populations attributed to S. scincus
and S. albifasciatus was carried out by conventional Giemsa staining. Both samples showed the same diploid number of 2N = 32 and identical chromosome morphology.
Therefore, these populations seem to be lacking in chromosome changes that could act as barriers to gene flow. However, because speciation in lizards is not always associated with chromosome repatterning, the taxonomic status of “scincus” and “albifasciatus” forms remains unsettled
Genetic variation among spiny-footed lizards in the Acanthodactylus pardalis group from North Africa
The systematics of the genus Acanthodactylus was classically based on external morphological traits, osteological characters and morphology of the hemipenes. Although the identification of species complexes is relatively easy, the distinction within some groups is difficult due to a high variability of the external morphology. Partial mitochondrial (12S and 16S rRNA) sequences (371 and 499 base pairs, respectively) were analysed from 32 specimens of the A. pardalis group from northern Africa including the described species A. busacki, A. maculatus, A. mechriguensis and A. pardalis. Several highly distinct genetic units were resolved, but with little support for relationships between them. These units did not coincide with current taxonomic units, but showed geographic structuring. Although the A. pardalis group displays significant variation, the present taxonomy of the group must be considered unsatisfactory since it is not supported by genetic evidence. For some forms, such as A. mechriguensis there is no support and it is suggested that it should be synonymized with A. maculatus. More data are clearly needed for other forms. Complex microevolutionary patterns due to the recent contraction/ expansion phases of the Sahara Desert probably are related with the phylogenetic patterns observed.Key words: Acanthodactylus pardalis, phylogeny, North Africa, mitochondrial DNA