The role of the National Trust in the conservation of British butterflies

The National Trust is of paramount importance in the conservation of butterflies in the UK on account of the scale of its land holding and its ability to manage habitats beneficially. Fifty two of the fifty four species currently regarded as resident in Britain occur on Trust land. The Trust has major responsibilities for the conservation of all bar one of the British rarities, and is of special significance in the conservation of the high brown fritillary and heath fritillary, two protected species. The Trust owns some 35 areas (many of which are large) of national importance for butterflies, plus much other property where the butterfly fauna is of regional importance. The Trust is implementing many dynamic projects aimed at conserving rare species, maintains a butterfly site data base and is developing a butterfly population monitoring programme. It is well placed to address the key issue of butterfly conservation on a metapopulation scale. To do this, it must work in partnership with other conservation organizations.     

Polarity of meiotic gene conversion is 5′ to 3′ within the niaD gene of Aspergillus nidulans

We have examined polarity of meiotic gene conversion in the niiA-niaD gene cluster of Aspergillus nidulans in two-point crosses. The type and position of the mutations represented by the niaD alleles and the correlation between the relative frequency of gene conversion and the physical position of these mutations were determined. We show that polarity of meiotic gene conversion is 5 to 3 (transcribed strand) within the niaD gene. Additional crosses involving a niiA allele and a niaD allele show little polarity of gene conversion, which suggests that the recombination events leading to restoration of the niaD gene are initiated upstream of the coding region of the niaD gene but within the niiA-niaD gene cluster, possibly within the intergenic promoter region.     

Seasonal variation in hydrochloric acid, malic acid, and calciumions secreted by the trichomes of chickpea (Cicer arietinum)

A novel experimental set-up and method of recording of electrical potential differences in plants have been developed which enable continuous, 8-channel monitoring of electrical activity over extended periods of time using inserted, extracellular electrodes. The investigations were carried out on 21- to 23-day-old Helianthus annuus plants, and spontaneously-generated action potentials were recorded during monitoring sessions lasting for 3 days and nights. Characteristics of these spontaneous action potentials were elaborated, adopting as parameters their typical form, amplitude, duration, velocity, direction, and distance of propagation and frequency of occurrence in morphologically different parts of the plant, Variability, similarities, and interdependence of the above parameters in individual plants and in a group of 15 plants were determined. A hypothesis concerning propagation of action potentials in plants along specific impulse-propagating 'columns' is discussed. The frequency of generated impulses is highest at night and lowest in the day and also displays an apparent 24-h rhythm. Presumably this mechanism is under both endogenous and exogenous control and may be partly dependent on a biological clock.     

Monitoring uptake and contents of Mg,Ca and K in Norway spruce as influenced by pH and Al,using microprobe analysis and stable isotope labelling

In a model system using intact spruce trees (Picea abies [L.] Karst.) we followed the path of magnesium, calcium and potassium during uptake into the root and during long-range transport into the shoot, by multiple stable isotope labelling. The roots of two- and three-year-old spruce trees originating from soil culture were removed from the soil and, in part or in toto, exposed to labelling solutions containing the stable isotopes ²⁵Mg or ²⁶Mg, ⁴¹K and ⁴²Ca or ⁴⁴Ca. Optical-emission-spectroscopy (ICP-OES) of plant fractions and labelling solutions was combined with the quantitative analysis of stable isotope ratios in sections of shock frozen, cryosubstituted material using the laser-microprobe-mass-analyser (LAMMA). This combination allowed us to distinguish, both in bulk samples and on the cellular level between (i) the fraction of elements originally present in the plant before the start of the labelling, (ii) the material taken up from the labelling solution into the plant and (iii) any material released by the plant into the labelling solution.In single-root labelling experiments, roots of three-year-old spruce trees, grown in nursery soil, were exposed to various pH conditions. The exchange of Mg and Ca with the labelling solution was nearly 100% in the cell walls of the mycorrhized finest roots. This exchange was only slightly affected by a step down to pH 3.5. The absolute Mg and Ca content in the cell walls was moderately reduced by incubation at pH 3.5 and strongly reduced in the presence of Al at this pH. After a pH 3.5 and 2 mM Al treatment we found Al in the xylem cell walls and the cortex cell lumina at elevated concentrations. To analyse the combined effect of high Al and high proton concentrations on the long-range transport, we used a split-root system. The root mass of an intact two-year-old spruce tree, grown in mineral soil, was divided into even parts and both halves incubated in solutions with two sets of different stable isotopes of Mg and Ca (side A: no Al, ²⁵Mg and ⁴²Ca; side B: +Al, ²⁶Mg and ⁴⁴Ca) and ⁴¹K on both sides. We observed a large uptake of Mg, Ca and K into the plant and a pronounced release. The net uptake of all three elements was lower from the Al-doted solution. In cross-sections of the apical shoot we found after seven-day labelling period about 60–70% of the Mg and Ca and 30% of the K content in the xylem cell walls originating from both labelling solutions. The clear majority of the Mg and Ca label originated from the Al-doted side.     

Rates of net nitrogen mineralization in disturbed and undisturbed soils

Quantification of net nitrogen mineralization (NNM) in soils is indispensable in order to optimize N fertilization of crops. Two long-term laboratory incubation methods were applied to determine rates of net nitrogen mineralization (r_NNM) of soils from two sites of arable land (sandy loam soil, silty loam soil) at four temperature levels (2°C, 8°C, 14°C, 21°C). Since variability within replicates was small, the modified 12-week incubation method of Stanford and Smith (1972) using disturbed soils allowed to establish reliable Arrhenius functions with reasonable expenditure. The fit of the functions derived from the 5-month incubation of 23 undisturbed soil columns (4420 cm³) was worse. This was caused by greater variability and less differentiation between temperature levels. Results of both experiments could be described best by zero-order kinetics. Mean mineralization rates of disturbed samples were approximately twice as high than those of undisturbed samples. The suitability of both methods for the prediction of NNM at site conditions is discussed. Actual respiration (AR) at incubation temperatures and substrate induced respiration (SIR) were measured at the end of the incubation of undisturbed soil columns. The results presented reveal that soil microbial communities develop in a different manner during long-term incubation at different temperatures. This behavior offends the underlying assumption that soil microbes remain in steady-state during incubation and that rising rates are physiological reactions to temperature enhancement. Therefore soil microbial biomass (SMB) dynamics during the experiment has to be accounted for when rates of NNM and Arrhenius functions are established. R Merck Section editor     

Rapid shifting of foraging pattern by Yakushima macaques ( Macaca fuscata yakui ) in response to heavy fruiting of Myrica rubra

We describe short-term changes in foraging behavior by wild Yakushima macaques (Macaca fuscata yakui),which inhabit a warm-temperate broad—leaved forest on Yakushima Island (30°N, 131°E), Japan. Rapid changes of dietary composition, activity budget, and range use by the monkeys occurred from May to June, apparently associated with changes in the availability of the fruit of Myrica rubraBefore the fruit ripened, monkeys spent less time moving and more time feeding on many species of leaves, which accounted for 40% of feeding time. However, when M. rubrabegan to ripen, they fed intensively on the fruit, which accounted for three-fourths of feeding time,though the activity budget remained unaffected As fiuit of M. rubradecreased,the monkeys fed more on the fruit of other species and on insects, and spent more time moving at higher speeds. There marked shifts in foraging pattern occurred within only two months. In terms of moving cost and dietary quality,Yakushima macaques shifted their foraging pattern according to the availability of M. rubrafrom a “low-cost, low-yield” strategy to a “low-cost, high-yield” strategy, and then to a more costly strategy. The ability to make such rapid shifts in foraging pattern may allow the macaques to effectively use the highly variable food supply within their small range.     

Synergism of thidiazuron and benzyladenine in axillary shoot formation depends on sequence of application in Miscanthus X ogiformis ‘Giganteus’

Shoots of Miscanthus X ogiformis Honda Giganteus transferred from medium with benzyladenine (BA) to thidiazuron (TDZ) formed significantly more axillary shoots than shoots grown continuously on either medium, or transferred from TDZ to BA. Shoot formation on axillary shoots transferred from BA-containing media to media with kinetin or isopentenyladenine (2iP) or transferred from media with TDZ, kinetin or 2iP to media with BA, corresponded to the number of shoots formed in the previous subculture. Shoot formation on shoots transferred from medium containing BA to media containing combinations of BA and/or TDZ increased with increasing concentrations of TDZ in the first subculture, whereas shoot formation in the second and third subculture depended on the BA concentration. When shoots were transferred from media with BA to media with TDZ, the time for shoot formation, as well as shoot size, indicate that the combined effect of BA and TDZ is expressed only during the early phase of the subculture. The results suggest that adenine- and phenylurea-type cytokinins have a common binding site in the plant cell, and a model is proposed.Abbreviations BA 6-benzyladenine - CBP cytokinin-binding protein - 2iP isopentenyladenine - KIN kinetin - MS Murashige & Skoog - TDZ thidiazuron     

Moral Darwinism: Ethical evidence for the descent of man

Could an ethical theory ever play a substantial evidential role in a scientific argument for an empirical hypothesis? InThe Descent of Man, Darwin includes an extended discussion of the nature of human morality, and the ethical theory which he sketches is not simply developed as an interesting ramification of his theory of evolution, but is used as a key part of his evidence for human descent from animal ancestors. Darwin must rebut the argument that, because of our moral nature, humans are essentially different in kind from other animals and so had to have had a different origin. I trace his causal story of how the moral sense could develop out of social instincts by evolutionary mechanisms of group selection, and show that the form of Utilitarianism he proposes involves a radical reduction of the standard of value to the concept of biological fitness. I argue that this causal analysis, although a weakness from a normative standpoint, is a strength when judged for its intended purpose as part of an evidential argument to confirm the hypothesis of human descent.     

Upper cretaceous rudist and stromatoporid associations of Central Oman (Arabian Peninsula)

Summary Rudist and stromatoporid associations of the Campanian from Central Oman are nearly monospecific. They are dominated byDurania aff.nicholasi, Vaccinites vesiculosus, Torreites milanovici or phaceloid and massive stromatoporids. Several other rudist genera play a secondary role. The thickness of the associations is rarely more than one metre. Solitary corals do not occur in the associations. Colonial corals are less common, although they are up to 1 m high and show considerable diversity. There are no binders. The reef structure indicates variable hydrodynamic conditions. They are always associated with very shallow water. The pureDurania aff.nicholasi patches with large colonial corals andTorreites milanovici are presumably the most rigid structures. The near monospecific associations ofVaccinites vesiculosus are widely distributed. Although mostly preserved in situ, strong currents, presumably caused by tropical storms, have repeatedly impaired and interrupted growth. The specific growth characteristics of the shell of some rudists, especially the radiolitids, enable an estimation of the individual lifespan. Frameworks of approximately 1 metre thickness probably developed in ±100 years. The sediments of the complete sections are predominantly bioclastic.