Total nitrogen and L-hydroxyproline content of adipose tissue from various sites in rats of different ages

The total nitrogen and L-hydroxyproline concentrations of two intra-abdominal and two subcutaneous sites of adipose tissue were measured in male and female Wistar rats. At 100 g body weight the nitrogen concentration of intra-abdominal adipose tissue was slightly lower than that of subcutaneous adipose tissue. As age advanced beyond sexual maturity, the nitrogen content of intra-abdominal adipose tissue was steadily reduced, whereas that of subcutaneous tissue did not change. The L-hydroxyproline concentration of intra-abdominal adipose tissue was also lower than in subcutaneous adipose tissue. In male rats it rose in most adipose tissue sites when sexual maturity was reached, then fell with advancing age. In female rats the pattern of change was less consistent, but the l-hydroxyproline content of intra-abdominal adipose tissue was reduced as age increased.     

The Ultrastructure of the Fungus Trichoderma viride and Investigation of its Growth on Cellulose

Changes in the ultrastructure of Trichoderma viride during growth in shake cultures on cellobiose and cellulose fibres were examined. Electron micrographs of thin sections of germinating conidia, septate hyphae with ascomycete pores and other cell organelles are presented. Extensive autolysis of hyphae was observed after growth for 20 h on cellobiose. The fungus grew in the lumina and within the walls of cellulose fibres. The hyphae followed the directions of the laminar structure but did not grow across them. The observations indicated that the hyphae penetrated the fibres by causing cracks and by dissolving enzymatically the cellulose.     

Population structure in an isolated Arctic fox, Vulpes lagopus, population: the impact of geographical barriers

The genetic composition of a population reflects several aspects of the organism and its environment. The Icelandic Arctic fox population exceeds 8000 individuals and is comprised of both coastal and inland foxes. Several factors may affect within-population movement and subsequent genetic population structure. A narrow isthmus and sheep-proof fences may prevent movement between the north-western and central part and glacial rivers may reduce movement between the eastern and central part of Iceland. Moreover, population density and habitat characteristics can influence movement behaviour further. Here, we investigate the genetic structure in the Icelandic Arctic fox population ( n  = 108) using 10 microsatellite loci. Despite large glacial rivers, we found low divergence between the central and eastern part, suggesting extensive movement between these areas. However, both model- and frequency-based analyses suggest that the north-western part is genetically differentiated from the rest of Iceland (F_ST = 0.04, D_S = 0.094), corresponding to 100–200 generations of complete isolation. This suggests that the fences cannot be the sole cause of divergence. Rather, the isthmus causes limited movement between the regions, implying that protection in the Hornstrandir Nature Reserve has a minimal impact on Arctic fox population size in the rest of Iceland.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 18–26.     

Phylogeographic analyses reveal distinct lineages of the liverworts Metzgeria furcata (L.) Dumort. and Metzgeria conjugata Lindb. (Metzgeriaceae) in Europe and North America

Seed plant genera often exhibit intercontinental disjunctions where different species are found on different continents. Many morphologically circumscribed bryophyte species exhibit similar disjunctions. We used nucleotide sequences from the plastid and nuclear genomes to test hypotheses of phylogeography within representatives of the genus Metzgeria: Metzgeria furcata, Metzgeria conjugata, and Metzgeria myriopoda. The first two species have sexual and asexual populations, exhibit disjunctions between North America and Europe, and have been split into separate species, numerous subspecies or varieties. The third species occurs in eastern North America but is not reported from Europe. Phylogenetic analyses resolved three distinct lineages within the morphologically defined species, M. furcata: one in North America, and two in Europe. Similarly, three morphologically cryptic clades of M. conjugata were resolved by the molecular data: northern North America, Europe, and south‐eastern North America. For both species, molecular divergence among taxa occurred in the absence of morphological change. In the case of M. myriopoda, all plants from eastern North America were both morphologically uniform and genetically homogeneous (although not identical). The present study provides significant insight into a plant group with complex taxonomy, and indicates that these liverwort taxa with wide distributions, extreme sex ratios, and continental disjunctions harbor cryptic lineages. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98 , 745–756.     

Determination of acid α-naphthyl acetate esterase enzyme activity in peripheral blood leukocytes of gazelles (Gazella subgutturosa)

We examined gazelle peripheral blood leucocytes using the α-Naphthyl acetate esterase (ANAE) staining technique (pH 5.8). Our purpose was to determine the percentage of ANAE positive lymphocytes. The proportion of ANAE positive T-lymphocytes was 72%. T-lymphocytes showed an ANAE positive reaction, but eosinophilic granulocytes and monocytes also showed a positive reaction. By contrast, no reaction was detected in B-lymphocytes, neutrophil granulocytes or platelets. The reaction observed in T-lymphocytes was a red-brown coloration, usually 1–2 granules, but enough granules to fill the cytoplasm were detected rarely. As a result of ANAE enzyme staining, we concluded that the staining technique can be used as a cytochemical marker for gazelle T-lymphocytes.     

Predation on Moose Calves by European Brown Bears

Abstract: In North America, brown bears (Ursus arctos) can be a significant predator on moose (Alces alces) calves. Our study in Sweden is the first in which brown bears are the only predator on moose calves. Bears and moose occurred at densities of about 30/1,000 km² and 920/1,000 km², respectively, and bears killed about 26% of the calves. Ninety-two percent of the predation took place when calves were <1 month old. Bear predation was probably additive to other natural mortality, which was about 10% in areas both with and without bears. Females that lost their calves in spring produced more calves the following year (1.54 calves/F) than females that kept their calves (1.11 calves/F), which reduced the net loss of calves due to predation to about 22%.     

Does freshwater macroinvertebrate diversity along a pH‐gradient reflect adaptation to low pH?

1. The impacts of anthropogenic surface water acidification are much better known than those of natural acidity. Recent studies have indicated biodiversity is not degraded and species composition unaltered in naturally acidic compared to circumneutral watercourses.
2. Here, we use a geographically extensive dataset comprising sites in more than 200 Swedish streams to test whether the lack of effects on macroinvertebrate species diversity is due to exaptation and adaptation to natural acidity.
3. To this end, we modelled pH associated with spring flood episodes, which inflict the most challenging hydrochemical conditions to the biota. We compared taxonomic richness and species composition along the modelled pH gradient in northern Sweden, where acidity is largely natural, with southern Sweden, a region influenced by significant anthropogenic acidification.
4. We found Plecoptera richness did not respond to varying pH either in northern or southern Sweden. Ephemeroptera richness was sensitive to pH in both regions, while that of Trichoptera increased with increasing pH in southern Sweden, but decreased in the north. The taxonomic composition of Plecoptera changed along the pH gradient in both regions, whereas that of Ephemeroptera and Trichoptera changed more strongly with pH in southern Sweden.
5. Our results support the hypothesis that stream invertebrates are able to tolerate low pH through exaptation or adaptation, but that this capability varies among taxonomic groups.     

Why study the use of animal products in traditional medicines?

The World Health Organization (WHO) estimates that as many as 80% of the world's more than six billion people rely primarily on animal and plant-based medicines. The healing of human ailments by using therapeutics based on medicines obtained from animals or ultimately derived from them is known as zootherapy. The phenomenon of zootherapy is marked both by a broad geographical distribution and very deep historical origins. Despite their importance, studies on the therapeutic use of animals and animal parts have been neglected, when compared to plants. This paper discusses some related aspects of the use of animals or parts thereof as medicines, and their implications for ecology, culture (the traditional knowledge), economy, and public health.     

Comparative studies in the morphology of Crenias weddelliana and Maferria indica with reference to Sphaerothylax abyssinica (Podostemaceae: Podostemoideae)

The scope of morphological plasticity of vegetative structures among Podostemoideae (Podostemaceae) is documented for Crenias weddelliana, a neotropical species, Maferria indica, a palaeotropical species, and Sphaerothylax abyssinica, from Kenya, and compared with related taxa. The study highlights intrinsic characters of the widely enigmatic plant body of many species of the subfamily Podostemoideae. These include dorsiventrality of shoots occurring irrespective of gravity, incurvate distichy and one‐sided spirodistichy correlated with shoot dorsiventrality, asymmetric leaves, and several types of positioning of the two prophylls and inflorescence structures. The homogeneity of hairs of the ‘Zeylanidium olivaceum type’ established on the subulate leaves of some Indian species is of taxonomic value. The latter also applies to the stipella (not stipule) on the asymmetric compound leaf in New World species. The morphological data represent a framework of features consistent for the subfamily. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 138 , 63–84.