Changes in bone structure and metabolism during simulated weightlessness: Endocrine and dietary factors

The role of vitamin D, PTH and corticosterone in the skeletal alterations induced by simulated weightlessness was examined. The first objective was to determine if changes in the serum concentrations of Ca, P sub i, osteocalcin, 25-OH-D, 24,25(OH)2D or 1,25(OH)2D also occur following acute skeletal unloading. Animals were either suspended or pair fed for 2, 5, 7, 10, 12 and 15 days and the serum concentrations of Ca, P sub i, osteocalcin and the vitamin D metabolites measured. Bone histology was examined at day 5 after suspension. Acute skeletal unloading produced a transient hypercalcemia, a significant fall in serum osteocalcin and serum 1,25(OH)2D, a slight rise in serum 24,25(OH)2D, but did not affect the serum concentrations of P sub i or 25-OH-D. At the nadir in serum 1,25(OH)2D serum osteocalcin was reduced by 22%, osteoblast surface by 32% and longitudinal bone growth by 21%

Seasonality of group size and group composition in Sand Partridges (Ammoperdix heyi heyi).

The seasonality of group size and composition in sand partridges was studied at the Ibex Reserve in central Saudi Arabia. Mean group size and fl ock encounter rate were signifi cantly related to rainfall and temperature. During winter and the breeding season (March to April), the encounter rate on the valley fl oors was distinctly lower than that observed during summer. Although encounter rates did not diff er signifi cantly between valleys, sand partridges were more likely to be encountered in narrow, stony valleys. Correcting for valley width, encounter rates did not diff er between valleys. Male and female encounter rates were constant throughout the reserve, indicating a constant sex ratio throughout the year. Results are in line with earlier fi ndings reported from more northern habitats such as the Eilat Mountains (Israel) and the Rum Wildlife Reserve (Jordan). Human disturbance in parts of the reserve is high and may have an impact on group size and composition

Distribution update of the Arabian wolf (Canis lupus pallipes) from Saudi Arabia

Since the first Arabian wolf records in late 1880’s from northern and central Saudi Arabia their actual distribution has been sketchy with wolves never viewed as being very common throughout their range. Although widespread throughout Saudi Arabia earlier publications indicate wolves either from the mountainous south western Asir, northern rocky areas bordering Jordan or the central areas around Riyadh. Being an understudied species, Arabian wolves are probably more widespread than currently documented and accordingly the species is listed as Least Concern (LC) with a stable population trend with a CITES protection status of CITES Appendix II. The status of wolves in Saudi Arabia is difficult to determine due to a lack of research and systematic census although estimated numbers vary between 500 and 700 animals. The only official census in Saudi Arabia to date was conducted during late 1999 and early 2000 by Sinibaldi et al. (2000) who concluded that the overall numbers might be higher albeit still in a decreasing trend. The aim of this paper is to update the distribution of Arabian wolf in Saudi Arabia by providing recent locations and data from unpublished field reports difficult to access from outside Saudi Arabia

Refuge theory and distribution patterns of land snails in Ugandan rain forests

Refuge theory assumes that the recent distribution of organisms is influenced by past, usually Pleistocene, environmental changes resulting in the contraction of ranges into refugia or the expansion of ranges from refugia. Refugia are areas that are less affected by environmental changes than the surrounding regions so that organisms that become extinct elsewhere can survive there. The existence and importance of Pleistocene refugia in the northern continents that were heavily affected by Pleistocene glaciations is universally accepted. However, the existence and role of refugia in the tropics is still controversial. Often the existence of refugia is inferred only from the recent distribution of species richness. However, several other patterns in the distribution of organisms are expected to originate, if retraction to refugia and expansion from refugia are processes that affect recent biogeography. Such patterns are nestedness of ranges (Hultén, 1937; Daubenmire, 1975; Hausdorf & Hennig, 2003a), clustering of ranges (***; Hausdorf & Hennig, 2004), and Rapoport effects (***; Pfenninger, 2004; Hausdorf, 2006). It is a long standing question whether the recent distribution of organisms can be explained by current ecological conditions alone or whether it shows the imprint of historical events (Endler, 1982a,b; ***). It has been assumed that the Pleistocene climatic cycles have resulted in cycles of retraction of ranges of organisms to refuges and expansions (***). Such hypotheses have been tested mainly for temperate regions. A retraction of biota into refugia and subsequent range expansions from such refugia will result is specific patterns in distribution data. Such processes should result in: 1. A decrease of species richness with increasing distance from the refuge; 2. Nestedness; that is the biota in regions more distant from the refuge will be subsets of the biota more closer to the refuge; 3. A Rapoport effect; that is the average range extension of the species belonging to a regional biota will increase with increasing distance from the refuge; 4. Clustering of ranges (biotic elements

Phylogenetic relationships and distribution of the enigmatic semislug Aillya (Gastropoda: Aillyidae)

Aillya is an enigmatic African semislug, which was originally classified into the American Amphibuliminae (Orthalicoidea) by Odhner. Later, Baker established a separate family for this group and placed it together with the Succineidae and Athoracophoridae in the suborder Heterurethra. Minichev & Slavoshevskaja subdivided the Heterurethra even into three separate orders and introduced the name Aillyida for the Aillyidae. In contrast, Pilsbry, Solem, Tillier and van Mol supposed that Aillya is most closely related to some limacoid groups, i.e. Helicarionidae or Urocyclidae. We investigated the phylogenetic relationships of Aillya based on ITS2 and partial 5.8S and 28S rDNA sequences. Furthermore, we examined the morphology of type specimens and newly collected material to clarify the taxonomy and distribution

Blanford's fox confirmed in the At-Tubaiq Protected Area (northern Saudi Arabia) and the Ibex Reserve (central Saudi Arabia)

Confirmed - new records - of Blanford's fox Vulpes cana from the At-Tubaiq Protected Area in northern Saudi Arabia and the Ibex Reserve in central Saudi Arabia extends the recognised range of the species within Saudi Arabia and the Arabian Peninsula

A literature review of mammalian research respective to the Akagera ecosystem in Rwanda

The Akagera NP (and the Mutara GR) in north-eastern Rwanda are considered part of the most complex and biodiversity rich savannah ecosystem in eastern Africa. Following the violent past of Rwanda, the park has recovered from civil war, poaching and overgrazing, counting today more than 12,000 large mammals. Since proclamation in 1934, a wealth of ecological research was carried in these protected areas. This literature review summarizes the available literature and puts it into a historical context, compiling more than 90 books, book chapters, and journal articles but also unpublished theses and reports respective to the ecology and conservation of mammals