The Use of Protamine-Coated Slides for Immobilizing Protozoa*

Fresh-water, marine or parasitic protozoa can be immobilized for microscopic observation on protaminecoated slides. They appear not to be harmed by this procedure. The type of protamine derivative and its concentration are important, best results being obtained with 0.015–0.05% (w/v) of protamine sulfate.     

Site prioritisation for the protection of rare subterranean species – the cases of two ostracods from south-western France

1. Delineation of protected areas for rare subterranean species is a key problem for groundwater biodiversity conservation, because of practical difficulties in implementation. Criteria for site selection are presented that are derived from studies on two remarkable Ostracoda, Dolekiella europaea Gidó, Artheau, Colin, Danielopol & Marmonier (Limnocytheridae) and Vestalenula carveli Artheau (Darwinulidae) discovered in south-western France.
2. Arguments for natural heritage value and protection of subterranean species are proposed and illustrated by using information on these two ostracod species. The proposed criteria are: (i) local and/or regional endemism; (ii) known occurrence of the species at a few localities only; (iii) representativeness for ancient phylogenetic lineages with wider geographical distributions in the past; and (iv) suitability for scientific study because of unique morphological or biological traits.
3. It is also proposed to prioritise the protection of subsurface sites using the following criteria: (i) type locality for newly described species; (ii) presence of other rare stygobiotic taxa; and (iii) high population densities of the primary target species.
4. Development and implementation of protection strategies at local scale are likely to benefit from collaboration between scientists, policy makers and stakeholders. The measures taken should complement existing national and/or international attempts at large-scale protection of groundwater biodiversity.     

Understanding Fluctuations in Bobcat Harvest at the Northern Limit of Their Range

ABSTRACT In Quebec, Canada, harvest of bobcats (Lynx rufus) started to decline in 1985 and by 1991, harvest seasons were closed due to concerns of a perceived population decline. Since the closing of harvest season in 1991, the average temperature has increased, snow quantity has decreased, and important changes in agriculture and forest management have occurred. In light of changing conditions, the situation of Quebec bobcats needed reassessment. Thus, we analyzed harvest data to clarify the current status of bobcat populations in Quebec. From 1980 to 1991, bobcat harvest in Quebec was strongly correlated with bobcat harvest in Maine (USA), Nova Scotia (Canada), Ontario (Canada), and Vermont (USA). Extrapolations of harvest in Quebec relative to harvest in Maine, Ontario, Vermont, and Nova Scotia suggested an increase in number of bobcats after 1991. Mass of male and female bobcats before 1991 was less than mass of animals captured after 1991. Percentage of juveniles in the reported harvest before 1991 was higher than after 1991. However, percentage of males and litter sizes in the harvest did not differ before and after 1991. The geographic distribution of bobcats captured has gradually expanded after the closure of the harvest season. Our findings suggest that bobcat populations in Quebec have recovered from the 1985–1991 decline, and that the harvest season for this species could resume. This study also illustrates how managers can rely on data from neighboring jurisdiction to manage species when local harvest data is unavailable.     

The rudist bivalve genus Gorjanovicia (Radiolitidae,Hippuritoidea) a revision of species based on quantitative analysis of morphological characters

Abstract: The rudist bivalve genus Gorjanovicia Pol?ak, 1967 from Istria, Croatia, is currently known from the Coniacian/Maastrichtian of the peri‐Adriatic and Balkan regions and includes 23 nominal species, defined mainly on shell ornamentation and radial bands. However, a re‐appraisal of ‘Radiolites’endrissi Boehm, 1927 shows the type species of the genus Gorjanovicia, G. costata Pol?ak, 1967, to be a junior synonym of Boehm’s species, which thus takes priority as the type species of Gorjanovicia. Our revision of the 24 species thus described from the literature is based on analysis of a set of 21 characters that include the dimensions, shape and ornamentation of the right valve. Sixteen variables are defined from combinations of these 21 characters and subjected to multiple correspondence analysis (MCA) and Hill and Smith analysis (HSA), with cluster analysis, which has allowed us to distinguish three taxonomic groups, each defined by a key species: Gorjanovicia endrissi (Boehm), G. ugarensis Sli?kovi? and G. kvarneri Pol?ak. Cluster analysis identifies three groups of associated variables and suggests that a limited number of characters may be used to recognize the foregoing three taxonomic entities. MCA performed on four variables (the shapes of the anterior radial band, posterior radial band and interband and the width of the anterior band relative to the posterior band) reveals the same three taxonomic groups as in the MCA based on 16 variables. We conclude that the four variables in question may thus be used as specific diagnostic characters and that the genus Gorjanovicia is thereby represented by just three species, Gorjanovicia endrissi, G. ugarensis and G. kvarneri, instead of the 24 described in the literature. Specific assemblages from the peri‐Adriatic, pre‐Apulian and Western Pontides regions are nearly identical, a pattern that suggests free faunal exchanges within the distributional area of the genus Gorjanovicia. The palaeobiogeographical distribution of species corresponds with a relatively narrow palaeolatitudinal range in the subtropical portion of the eastern Mediterranean Tethys.     

Global change and root function

Global change includes land-use change, elevated CO₂ concentrations, increased temperature and increased rainfall variability. All four aspects by themselves and in combination will influence the role of roots in linking below- and above-ground ecosystem function via organic and inorganic resource flows. Root-mediated ecosystem functions which may be modified by global change include below-ground resource (water, nutrients) capture, creation and exploitation of spatial heterogeneity, buffering of temporal variations in above-ground factors, supply and storage of C and nutrients to the below-ground ecosystem, mobilization of nutrients and C from stored soil reserves, and gas exchange between soil and atmosphere including the emission from soil of greenhouse gases. The theory of a functional equilibrium between root and shoot allocation is used to explore predicted responses to elevated CO₂ in relation to water or nutrient supply as limiting root function. The theory predicts no change in root:shoot allocation where water uptake is the limiting root function, but substantial shifts where nutrient uptake is (or becomes) the limiting function. Root turnover will not likely be influenced by elevated CO₂, but by changes in regularity of water supply. A number of possible mechanisms for root-mediated N mineralization is discussed in the light of climate change factors. Rhizovory (root consumption) may increase under global change as the balance between plant chemical defense and adapted root consuming organisms may be modified during biome shifts in response to climate change. Root-mediated gas exchange allows oxygen to penetrate into soils and methane (CH₄) to escape from wetland soils of tundra ecosystems as well as tropical rice production systems. The effect on net greenhouse gas emissions of biome shifts (fens replacing bogs) as well as of agricultural land management will depend partly on aerenchyma in roots.     

Postzygotic isolation between the two European subspecies of the house mouse: estimates from fertility patterns in wild and laboratory-bred hybrids

We assessed the fertility (reproductive success, litter size, testis weight, spermatocyte-to-spermatid ratio) of F₁s and backcrosses between different wild-derived outbred and inbred strains of two mouse subspecies, Mus musculus domesticus and M. m. musculus . A significant proportion of the F₁ females between the outbred crosses did not reproduce, suggesting that female infertility was present. As the spermatocyte-to-spermatid ratio was correlated with testis weight, the latter was used to attribute a sterile vs. fertile phenotype to all males. Segregation proportions in the backcrosses of F₁ females yielded 11 (inbred) to 17% (outbred) sterile males, suggesting the contribution of two to three major genetic factors to hybrid male sterility. Only one direction of cross between the inbred strains produced sterile F₁ males, indicating that one factor was borne by the musculus X-chromosome. No such differences were observed between reciprocal crosses in the outbred strains. The involvement of the X chromosome in male sterility thus could not be assessed, but its contribution appears likely given the limited introgression of X-linked markers through the hybrid zone between the subspecies. However, we observed no sterile phenotypes in wild males from the hybrid zone, although testis weight tended to decrease in the centre of the transect.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 379–393.