Body size – prey size relationships in European stoats Mustela erminea: a test case

From the close correlation between the body size of European stoats and the mean size of their vertebrate prey it ought to be possible to predict the body size of European stoats living on a prey fauna of a given size distribution. In New Zealand, stoats of European stock have lived for > 100 yr on a prey fauna containing fewer small and more large vertebrate prey than in Europe. They have become generally larger than their ancestors, as expected – especially the females. The vertebrate prey size index for New Zealand stoats extends the correlation predicted from European data. New Zealand stoats also eat large numbers of native insects. If these are included the local prey size indices are lower but still tend to vary with the substantial local variation in body size of stoats within New Zealand. Recent results from southern Ireland also fit the European correlation, but the few data so far available from Northern Ireland do not.     

Route,speed and mode of oak postglacial colonisation across the British Isles: Integrating molecular ecology,palaeoecology and modelling approaches

Summary

This paper describes the route, speed and mode of colonisation of oaks by integrating a number of independent analyses using molecular ecology, palaeoecology and simulation modelling approaches. Using a synthetic map of the contemporary distribution of chloroplast DNA (integrating several published and unpublished data sets and describing variation in 1468 trees from 313 autochthonous stands of Q. robur and Q. petraea from Britain and Ireland), and considering the postglacial topographic landscape, the most likely routes of postglacial colonisation across the British Isles are suggested. The overall pattern of these directions agrees with previous interpretations, but several routes, particularly those into Ireland, differ from previous interpretations and benefit here from using a single synthesised data set. Interestingly, the Atlantic oakwoods appear to have been colonised by individuals bearing a single haplotype (type 12). Two palaeoecology data sets, published separately for Britain and Ireland, are synthesised here and used to infer the timing of first arrival of oaks across the British Isles (between 9500 and 6000 years before present). The maximum observed colonisation speed within the British Isles is approximately 500 m year^-1 in central and southern England. Outputs from a simulation model, which mimics postglacial colonisation processes, and which has been parameterised for the colonisation rate observed from the pollen core record and contemporary cpDNA structure, predict that the rapid colonisation rate observed, for at least the southern portion of the British Isles, can only be achieved via very rare (an approximate frequency 0.01%), very long distance seed dispersal events (up to 100 km). Potential agents of such dispersal events are birdsor major meteorological disturbances, e.g. hurricanes. Additional simulation modelling and genetic analysis of latitudinally stratified populations indicate that non-synchronous colonisation fronts, topographic barriers and temperature related survival may also have had an effect on the speed of migration and resulting genetic structure. Finally, in an attempt to record predicted long distance seed dispersal events, a novel curve fitting technique is applied to molecular parentage assignment data for field established seedlings from a contemporary population. A notable discrepancy is recorded between contemporary field estimates (just over 1 km) and those predicted by simulation modelling, and is discussed in detail. A concluding section describes future research priorities.     

On the genetic interrelationships of South African Negroes

This study addresses the comparative genetic interrelationships between South African Negro groups. For this the genetic distances between seven ethnically defined Negro subsamples (total of 998 individuals) based on 24 genetic loci/polymorphisms are calculated by applying standard distance formulae. These computations offer an opportunity to evaluate the different polymorphisms in terms of their effects on the genetic distances. The genetic interrelationships thus computed are illustrated by way of dendrograms and are discussed in terms of their comparative significance. It follows from the findings that the Ndebele, Northern Sotho (Pedi), and Tswana form a closely related subcluster and that the Zulu and Swazi as well as the Venda and Shangana-Tsonga form two additional, more distant, subclusters. These results are discussed and tentatively interpreted against the background of the reported Khoisan admixture of the populations concerned as well as their ethnological history. The data are also compared to those derived from metric and dermatoglyphic studies. It is concluded that whereas there is some agreement between these categories of variation (genetic, metric, and dermatoglyphic) as far as the comparative evaluation of South African Negro groups is concerned, there also are discrepancies. These conclusions need to be explained in terms of evolutionary mechanisms (such as historic origins, hybridization, natural selection, and genetic drift) in order to obtain a more consistent and comprehensive comparative picture of the physical anthropology of southern African populations.     

Do soil organisms affect aboveground litter decomposition in the semiarid Patagonian steppe, Argentina?

Surface litter decomposition in arid and semiarid ecosystems is often faster than predicted by climatic parameters such as annual precipitation or evapotranspiration, or based on standard indices of litter quality such as lignin or nitrogen concentrations. Abiotic photodegradation has been demonstrated to be an important factor controlling aboveground litter decomposition in aridland ecosystems, but soil fauna, particularly macrofauna such as termites and ants, have also been identified as key players affecting litter mass loss in warm deserts. Our objective was to quantify the importance of soil organisms on surface litter decomposition in the Patagonian steppe in the absence of photodegradative effects, to establish the relative importance of soil organisms on rates of mass loss and nitrogen release. We estimated the relative contribution of soil fauna and microbes to litter decomposition of a dominant grass using litterboxes with variable mesh sizes that excluded groups of soil fauna based on size class (10, 2, and 0.01 mm), which were placed beneath shrub canopies. We also employed chemical repellents (naphthalene and fungicide). The exclusion of macro- and mesofauna had no effect on litter mass loss over 3 years (P = 0.36), as litter decomposition was similar in all soil fauna exclusions and naphthalene-treated litter. In contrast, reduction of fungal activity significantly inhibited litter decomposition (P < 0.001). Although soil fauna have been mentioned as a key control of litter decomposition in warm deserts, biogeographic legacies and temperature limitation may constrain the importance of these organisms in temperate aridlands, particularly in the southern hemisphere.     

Unique mitochondrial DNA lineages in Irish stickleback populations: cryptic refugium or rapid recolonization?

Repeated recolonization of freshwater environments following Pleistocene glaciations has played a major role in the evolution and adaptation of anadromous taxa. Located at the western fringe of Europe, Ireland and Britain were likely recolonized rapidly by anadromous fishes from the North Atlantic following the last glacial maximum (LGM). While the presence of unique mitochondrial haplotypes in Ireland suggests that a cryptic northern refugium may have played a role in recolonization, no explicit test of this hypothesis has been conducted. The three‐spined stickleback is native and ubiquitous to aquatic ecosystems throughout Ireland, making it an excellent model species with which to examine the biogeographical history of anadromous fishes in the region. We used mitochondrial and microsatellite markers to examine the presence of divergent evolutionary lineages and to assess broad‐scale patterns of geographical clustering among postglacially isolated populations. Our results confirm that Ireland is a region of secondary contact for divergent mitochondrial lineages and that endemic haplotypes occur in populations in Central and Southern Ireland. To test whether a putative Irish lineage arose from a cryptic Irish refugium, we used approximate Bayesian computation (ABC). However, we found no support for this hypothesis. Instead, the Irish lineage likely diverged from the European lineage as a result of postglacial isolation of freshwater populations by rising sea levels. These findings emphasize the need to rigorously test biogeographical hypothesis and contribute further evidence that postglacial processes may have shaped genetic diversity in temperate fauna.     

滇西北中甸的两栖爬行动物

滇西北中甸地区共有两栖类13种（亚种）,隶属于2目5科;爬行动物11种（亚种）,隶属于1目2亚目5科。区系成分以东洋界西南区的种类占主导地位,两栖类占84．6％,爬行类占72．7％。区系特点表现为：区系组成单一却特有率高,成分古老又兼具年轻特点,南北动物交汇形成多样化。两栖爬行动物的种群分布与植被类型具有密切的相关性;为适应环境动物形态发生了较多变化。认为中甸地区是动物地理区划中的一关键地区,其两栖爬行类动物的调查及分类研究工作尚需进一步深入。     

Methods of classifying nemerteans: an assessment

Phenetic, cladistic and phyletic methods of classifying animals are discussed with particular reference to nemerteans. It is concluded that phenetic (numerical) taxonomy is particularly inapplicable to any group of invertebrates for which well defined character differences are relatively few, whilst both the phenetic and cladistic methods fail through their fundamental assumption that convergent evolution is a rare occurrence. Terrestrial and freshwater nemerteans especially demonstrate convergent evolution in many ways; cladistic classifications proposed for these animals are therefore untenable. Convergence is shown to be a common occurrence in other nemerteans also. It is concluded that because the traditional phyletic approach does not implicitly assume that resemblances between organisms are more likely to be due to common ancestry than to convergence, it is far more likely to reveal true evolutionary relationships between taxa.     

Equipment Review

A quantitative survey of the fauna of a garden compost heap showed it to be similar to that of soil and leaf litter. The greatest biomasses of animals identified were earthworms, molluscs, and woodlice respectively. Animals were most abundant in the upper levels. The addition of various groups of animals to experimental composts allowed the direct estimation of their effect upon primary decomposition and of their role in the compost heap. Microbial populations played by far the greatest role in primary decomposition; earthworms and enchytraeids had smaller but significant roles. The addition of other animals had no significant effect.     

Trends in incidence of,and mortality from,cervical lesions in Ireland: Baseline data for future evaluation of the national cervical screening programme

AimTo investigate incidence and mortality trends for cervical lesions in Ireland in the period 1994–2008.MethodsWe used data from the National Cancer Registry, Ireland and national death registration data to calculate age-standardised rates for the periods of interest. We used standardised rate ratios to test whether incidence was associated with socio-demographic variables and used Joinpoint to examine trends by morphology grouping.ResultsIncidence of cervical cancer and cervical intraepithelial neoplasia (CIN3) rose over the period 1994–2008. The annual percentage change for cervical cancer was 1.8% and that for CIN3 was 3.8%. Women resident in the most deprived areas had invasive cervical cancer incidence almost twice as high as those resident in the least deprived areas (standardised rate ratio (SRR) = 1.8). Comparing incidence in Ireland to England and Wales, Northern Ireland and Scotland in the three years 2005–2007, the SRRs (other areas vs. Ireland) were 0.70, 0.88 and 0.84 respectively. Cervical cancer rates have fallen in these countries in the same period that there is a rise demonstrated in Ireland.ConclusionIncidence rates of cervical cancer rose in Ireland steadily, albeit modestly, during 1994–2008, most likely due to long-term changes in patterns of sexual behaviour and contraceptive use. A more pronounced rise in CIN3 rates point to considerable levels of opportunistic screening during this period. Mortality rates have changed little over the past four decades, in contrast to trends in countries with well-organised screening programmes.     

Animal survival strategies in Neoproterozoic ice worlds

The timing of the first appearance of animals is of crucial importance for understanding the evolution of life on Earth. Although the fossil record places the earliest metazoans at 572–602 Ma, molecular clock studies suggest a far earlier origination, as far back as ~850 Ma. The difference in these dates would place the rise of animal life into a time period punctuated by multiple colossal, potentially global, glacial events. Although the two schools of thought debate the limitations of each other's methods, little time has been dedicated to how animal life might have survived if it did arise before or during these global glacial periods. The history of recent polar biota shows that organisms have found ways of persisting on and around the ice of the Antarctic continent throughout the Last Glacial Maximum (33–14 Ka), with some endemic species present before the breakup of Gondwana (180–23 Ma). Here we discuss the survival strategies and habitats of modern polar marine organisms in environments analogous to those that could have existed during Neoproterozoic glaciations. We discuss how, despite the apparent harshness of many ice covered, sub-zero, Antarctic marine habitats, animal life thrives on, in and under the ice. Ice dominated systems and processes make some local environments more habitable through water circulation, oxygenation, terrigenous nutrient input and novel habitats. We consider how the physical conditions of Neoproterozoic glaciations would likely have dramatically impacted conditions for potential life in the shallows and erased any possible fossil evidence from the continental shelves. The recent glacial cycle has driven the evolution of Antarctica's unique fauna by acting as a “diversity pump,” and the same could be true for the late Proterozoic and the evolution of animal life on Earth, and the existence of life elsewhere in the universe on icy worlds or moons.     

Press responses to the presence of free-living Wild Boar (Sus scrofa) in southern England

Wildlife management and conservation programmes are likely to attract media attention, especially when the programmes in question involve large mammals. The present study surveyed the response of the press (national and local newspapers, and magazines) to the existence of two populations of free‐living Wild Boar (Sus scrofa) that established in southern England in the early 1990s, following the escape of animals from captivity. One‐hundred and seven target articles from 46 different titles were searched for references to 18 separate issues related to topics such as agricultural damage, risk to humans and ecological impact. The presence of free‐living Wild Boar in the English countryside attracted predominantly negative press coverage: the issues most frequently raised by newspaper and magazine articles were that the animals constitute a danger to the public, damage agricultural crops, predate livestock and transmit disease. A minority of articles argued that the animals should be conserved, mainly on the grounds that they could be hunted for meat. There was relatively little coverage of environmental issues, and what there was tended to focus on detrimental effects of Wild Boar on native flora and fauna. We conclude that management and conservation programmes involving large, allegedly dangerous mammals are likely to encounter an adverse press reaction. This is something that the organizers of such programmes may need to take into account when predicting public attitudes.     

Origin of, and conservation units in, the Irish red squirrel (Sciurus vulgaris) population

Knowledge of genetic relationships among wildlife populations is fundamental to their conservation, particularly where translocations are concerned. This study involved a survey of mitochondrial DNA variation in the Irish red squirrel population. Our main aims were: (1) to determine whether the Irish red squirrel population is distinct from that found in Britain, given known translocations that took place from Britain in the 1800’s; and (2) whether inclusion of Irish data into a reanalysis of European red squirrel data could reveal patterns of postglacial spread in Ireland. We found evidence that the current Irish red squirrel population may be a mixture of native and translocated stock, and relationships between Irish and European haplotypes supported a number of colonisation events of the island. Although only one haplotype was common to both Ireland and Britain, it is probable that the most common haplotypes in Ireland are British introductions that have since become extinct in Britain. There was a significant regional genetic structure in Ireland (P < 0.001), as well as between all Irish and British regions. Although it is likely that the red squirrel will not be fundamental in tracing the colonisation of Ireland by mammals, the data demonstrated that individual regions within Ireland, as well as the Irish population as a whole, are distinct both from the British population and from each other and, therefore, these populations should be treated as separate Management Units (MU) in conservation strategies.     

The Near-bottom Layer as an Ecological Boundary in Marine Ecosystems: Diversity, Taxonomic Composition and Community Definitions

The near-bottom layer of the ocean represents a boundary between two oceanic biotopes (pelagial and benthal), and as a result, the animal populations living in this habitat belong to various diverse ecological groups. There is a profusion of terms to designate the organisms which live near the sea bottom, both in relation to their behaviour and to boundary-layer hydrodynamics. Do the fauna living above the sea bottom form a true community? Should the fauna in this habitat be considered as a true community or a mixed assemblage comprised of benthic and pelagic organisms? Between 1988 and 1996, more than 500 suprabenthic hauls were taken with a modified Macer-GIROQ sledge at 15 sites in the English Channel and the Seine Estuary (5–70 m), at 13 sites on the southern edge of the Cap Ferret Canyon (Bay of Biscay, 350–1100 m), and at 8 sites on the Atlantic seamounts south of the Azores (260–2235 m). This intensive sampling permitted the collection of more than several hundred species and will serve to facilitate discussion concerning the biodiversity of the fauna collected near the sea bottom. This paper proposes that in the estuary, the near-bottom layer is colonized by a mixed assemblage of both pelagic and benthic organisms, while in the coastal and in the bathyal zones, the response to the gradual extinction of light and the decreasing benthic resuspension at near-bottom depths leads to an ecocline.     

How do earthworms affect microfloral and faunal community diversity?

Much of the work regarding earthworm effects on other organisms has focused on the functional significance of microbial-earthworm interactions, and little is known on the effects of earthworms on microfloral and faunal diversity. Earthworms can affect soil microflora and fauna populations directly and indirectly by three main mechanisms: (1) comminution, burrowing and casting; (2) grazing; (3) dispersal. These activities change the soil's physico-chemical and biological status and may cause drastic shifts in the density, diversity, structure and activity of microbial and faunal communities within the drilosphere. Certain organisms and species may be enhanced, reduced or not be affected at all depending on their ability to adapt to the particular conditions of different earthworm drilospheres. A large host of factors (including CaCO₃, enzymes, mucus and antimicrobial substances) influence the ability of preferentially or randomly ingested organisms to survive (or not) passage through the earthworm gut, and their resultant capacity to recover and proliferate (or not) in earthworm casts. Small organisms, particularly microflora and microfauna, with limited ability to move within the soil, may benefit from the (comparatively) long ranging movements of earthworms. Microflora and smaller fauna appear to be particularly sensitive to earthworm activities, and priming effects enhancing nutrient release, particularly in casts, are common. Larger fauna such as microarthropods, enchytraeids and Isopods may be enhanced under some conditions (e.g., in earthworm middens), but in other cases earthworm activity may lead to a decrease in their populations due to competition for food (microbes and organic materials), and spatial and temporal changes in food abundance. Nevertheless, considering the presently available data, the beneficial interactions of earthworms and microflora and fauna appear to far outweigh the potential negative effects. However, much is still unknown regarding the interactions of earthworms of different ecological categories on the diversity and function of microfloral and faunal communities, and much more interdisciplinary research is needed to assess the potential role of earthworms in regulating the diversity of microflora and fauna in soil systems and the potentially beneficial or harmful effects this regulation may have on ecosystem function and plant growth in different ecosystems.     

Assessment of the global potential distribution of the predatory land planarian Artioposthia triangulata (Dendy) (Tricladida: Terricola) from ecoclimatic data

Abstract

Artioposthia triangulata was originally described from New Zealand in 1895 but was subsequently found to have spread to Northern Ireland in 1963 and Scotland and England in 1965. It is now widespread in both Ireland and Scotland, where it has been shown to reduce earthworm numbers to below detectable levels. Ecoclimatic data were used in the computer program CLIMEX to estimate the potential spread of A. triangulata to Europe and the rest of the world. Results indicated it could establish in agricultural land in most of north‐western Europe, and persist in domestic gardens throughout much of central Europe, east and west North America, Australia, southern South America, and South Africa. It is difficult to assess either the extent to which earthworm numbers and diversity would be decreased or how far the effect of their loss to soil structure, nutrient cycling, or wildlife would be detrimental in these areas.     

Retracing the history and planning the future of the red squirrel (<Emphasis Type="Italic">Sciurus vulgaris</Emphasis>) in Ireland using non-invasive genetics

The Eurasian red squirrel’s (Sciurus vulgaris) history in Ireland is largely unknown, but the original population is thought to have been driven to extinction by humans in the seventeenth century, and multiple records exist for its subsequent reintroduction in the nineteenth century. However, it is currently unknown how these reintroductions affect the red squirrel population today, or may do so in the future. In this study, we report on the development of a DNA toolkit for the non-invasive genetic study of the red squirrel. Non-invasively collected red squirrel samples were combined with other samples collected throughout Ireland and previously published mitochondrial DNA (mtDNA) data from Ireland, Great Britain and Continental Europe to give an insight into population genetics and historical introductions of the red squirrel in Ireland. Our findings demonstrate that the Irish red squirrel population is on a national scale quite genetically diverse, but at a local level contains relatively low levels of genetic diversity, and there is also evidence of genetic structure. This is likely an artefact of the introduction of a small number of genetically similar animals to specific sites. A lack of continuous woodland cover in Ireland has prevented further mixing with animals of different origins that may have been introduced even to neighbouring sites. Consequently, some of these genetically isolated populations are or may in the future be at risk of extinction. The Irish red squirrel population contains mtDNA haplotypes of both a British and Continental European origin, the former of which are now extinct or simply not recorded in contemporary Great Britain. The Irish population is therefore important in terms of red squirrel conservation not only in Ireland, but also for Great Britain, and should be appropriately managed.     

Chloroplast DNA intraspecific phylogeography of plants from the Pacific Northwest of North America

Molecular studies of plants from the Pacific Northwest of North America suggest a recurrent pattern of genetic differentiation and geographic structuring. In each of five angiosperms and one fern species representing diverse life histories, cpDNA data indicate two clades of populations that are geographically structured. A northern group comprises populations from Alaska to central or southern Oregon, whereas populations from central Oregon southward to northern California form a southern group. In several of these species, a few populations having southern genotypes may have survived in glacial refugia further north in the Olympic Peninsula, Queen Charlotte Islands, and Prince of Wales Island. Allozyme data reveal a similar pattern of differentiation in several other plants from the Pacific Northwest. North-south partitioning of genotypes has also been reported for several animal species from this region. On a broader geographic scale, northsouth partitioning of genotypes has also been observed in other plants from western North America having a variety of geographic distributions. Some species also display a reduction of genetic variability in the northern portion of their range compared to the south. The data suggest strongly that past glaciation profoundly influenced the genetic architecture of the flora and fauna of the Pacific Northwest. Two alternative hypotheses are advanced to explain the geographic structuring of genotypes. First, past glaciation may have created discontinuities in the geographic distributions of plant species, with populations surviving in several well-isolated northern and southern refugia. Following glaciation, migration of genetically differentiated, once-isolated populations resulted in the formation of a continuous geographic distribution with a major genetic discontinuity. Alternatively, plants survived and subsequently migrated northward from a southern refugium, and a genotype became fixed in one or a few populations at the leading edge of recolonization. Subsequent long-distance dispersal from this leading edge resulted in a relatively uniform northern genotype that differs from the southern genotype(s). Whatever the underlying mechanism, Pleistocence glaciation may have molded the intraspecific genetic architecture of both plants and animals from the Pacific Northwest in a geographically similar manner. Future studies should seek to obtain a comprehensive phylogeography for regions that includes a diversity of both plants and animals.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday     

A regression technique for the estimation of epiphytic invertebrate populations*

SUMMARY. 1. A regression method is proposed for the estimation of populations of epiphytic invertebrates. Small samples of macrophytes and attached animals are taken by gentle enclosure. Regression analysis is used to relate the number of animals collected to the macrophyte species composition and ibiomass in these small samples. These relationships estimate the number of organisms of each taxon per unit mass of each macrophyte species. Areal population density is estimated by multiplication of macrophyte mass-specific invertebrate density by standing macrophyte biomass. 2. The regression method yields population density estimates several times greater than the best of current methods for several fauna. Differences are most pronounced for active organisms such as water mites, amphipods, cladocerans, copepods, lepidopterans, ostracods, and trichopterans. 3. Precision levels obtained using the regression method are comparable to other techniques. The regression technique automatically provides estimates of macrophyte species-specific colonization density and the abundance of organisms swimming among macrophytes in littoral areas.     

A re-examination of the Lansing effect

Traunsee is the deepest (189 m) lake in Austria and has been holomictic until the beginning of industrial discharges from the alkali works in Ebensee. The input of soluble compounds such as CaCl₂ and NaCl have produced meromictic conditions. The relatively high oxygen content of the monimolimnion is due to water movements promoted by the large inflow and wind-action.The industrial discharges have caused both meromictic conditions and the deposition of highly alkaline sediment in the southern portion of the profundal zone. The effect of the discharges on the benthic fauna was evaluated by comparing the subfossil benthic fauna of four cores taken inside and outside the affected area.The ostracod fauna resembles that of other large lakes in the Salzkammergut, but also includes groundwater species such as Kovalevskiella and Cypridopsis subterranea. Leucocythere mirabilis has been found for the first time in an Austrian lake.Ostracods and other benthic organisms such as Testacea were not apparently influenced by the meromictic condition. They are, however, missing in all areas covered by the alkaline sludge.