Indo-australian insular elephants

Various Pleistocene dwarfed elephants known from the islands of Celebes, Flores and Timor in the eastern part of the Malay Archipelago are described and their relationships considered. It is evident that these pygmy forms arose independently on each of the islands as a result of isolation and genetic drift favouring small size as in the better-known cases of the Mediterranean and Santa Barbara Channel Islands dwarf species. The dispersal possibilities of elephants are discussed; the conclusion must be drawn that geographic spacing has been the prime factor in species formation. Idle or fruitless speculations about ecological or other non-morphological species criteria have been omitted; the taxonomy of proboscideans as far as needed in the present context is however elucidated. It is pointed out that wherever we find pygmy elephants we have also giant rodents; in these presumably small isolated populations giganticism in small rodents appears to have been as advantageous to the animals as is dwarfing in elephants. As neither the exact date of colonization nor that of the eventual extinction (brought about by man or otherwise) is known, we have no means of knowing how many generations were involved; it is, however, likely that evolutionary velocity has been higher under these conditions than is usual.     

No-take areas for sustainability of harvested species and a conservation invariant for marine reserves

Various kinds of no-take areas (refuges, reserves) are gaining attention as conservation tools. The efficacy of reserves can be considered from the perspectives of providing baseline data sets, protecting the stock, maximizing yield to the fishery, or some combination of these. Regardless of the measure of effectiveness of a reserve, practical application requires the development of techniques for settling operational and policy questions such as how large a reserve should be. A simple model, involving population growth and harvest, is used to explore how the fraction of habitat assigned to a reserve affects the sustainability of a take and to frame the trade-off between control of harvest outside of the reserve and the size of the reserve. This exploration also leads to the discovery of a robust conservation invariant for reserves.     

Monitoring options for visitor numbers in national parks and natural areas

Identifying the physical behaviours of visitors is an essential component of visitor impact management in protected areas. The fundamental baseline information required is visitor numbers, and particularly how these are distributed in time and space across the protected areas. However, obtaining such counts in a reliable and cost-effective manner has proven to be more difficult than commonly expected. Reasons for this difficulty are reviewed, the range of visitor monitoring options available to park managers are described, and the features that park managers want in their visitor counting tools are summarised. The management requirements for implementing and operating an effective monitoring system are also presented.     

Monitoring for management of conservation and recreation in Australian protected areas

Protected areas are key to conservation of biodiversity, and Australia is one of the world’s megadiverse regions. Monitoring programs provide the information to assess the state of conservation resources, the severity of threats and the success of management responses. Here we compare the management priorities, monitoring priorities and actual monitoring practices of protected area management agencies in Australia, using four sets of data at continental scale and five at a more restricted regional scale. We track changes over a period of several years and focus at successively finer levels of detail. At both continental and regional scales, most management plans emphasise fire, invasive species and visitor management; and most monitoring programmes refer to visitor numbers and impacts as well as species and ecosystems. There is only a weak match, however, between reported management priorities and actual monitoring programmes; and the effectiveness of management responses is rarely monitored. The level of detail in visitor monitor programmes varies considerably: most parks count visitors, but few know what those visitors do. Threats from fire and invasive species receive more attention that those from recreation. At regional scale, the proportion of parks with defined monitoring programmes and priorities increased significantly from 2003/2004 to 2006/2007. Whilst only a proportion of protected areas monitor endangered species populations, for those that do this is the parameter reported in most detail, with many parks reporting single records of single individuals. Some parks also maintain anecdotal records of rare species outside routine monitoring programs.     

Extreme insular dwarfism evolved in a mammoth

The insular dwarfism seen in Pleistocene elephants has come to epitomize the island rule; yet our understanding of this phenomenon is hampered by poor taxonomy. For Mediterranean dwarf elephants, where the most extreme cases of insular dwarfism are observed, a key systematic question remains unresolved: are all taxa phyletic dwarfs of a single mainland species Palaeoloxodon antiquus (straight-tusked elephant), or are some referable to Mammuthus (mammoths)? Ancient DNA and geochronological evidence have been used to support a Mammuthus origin for the Cretan ‘Palaeoloxodon’ creticus, but these studies have been shown to be flawed. On the basis of existing collections and recent field discoveries, we present new, morphological evidence for the taxonomic status of ‘P’. creticus, and show that it is indeed a mammoth, most probably derived from Early Pleistocene Mammuthus meridionalis or possibly Late Pliocene Mammuthus rumanus. We also show that Mammuthus creticus is smaller than other known insular dwarf mammoths, and is similar in size to the smallest dwarf Palaeoloxodon species from Sicily and Malta, making it the smallest mammoth species known to have existed. These findings indicate that extreme insular dwarfism has evolved to a similar degree independently in two elephant lineages.     

Abundance-age-area relationships in an insular plant community

Two processes are thought to generate positive relationships between species richness and island area. The areaper se hypothesis states that larger islands maintain larger populations, which are less susceptible to extinction. The habitat hypothesis states that larger islands contain more habitats, and therefore a greater number of habitat specialists. However, the importance of each mechanism is debated. I tested the areaper se and habitat hypotheses by comparing relationships between plant abundance, age and island area in five shrub species on islands off the coast of British Columbia, Canada. Results showed that two shrub species increased in both abundance and age with island area. The remaining three species showed no differences in abundance and age with island area. Conifer abundances increased with island area, which generated differences in habitat availability. Smaller islands were dominated by open habitat, while larger islands contained both open and forested habitats. Changes in habitat availability with island area could explain patterns in plant abundance and age. The two species that increased in abundance with island area were commonly found in conifer forest on the mainland, and their distributions were consistent with the distribution forest habitat. Positive relationships between plant age and island area in these two species may result from lower survivorship in the open habitat, which dominated small islands. The three species that showed no relationship between abundance and island area are commonly found in open habitat on the mainland, and their island distributions paralleled the availability of open habitat on islands. Similar plant ages on different sized islands may result from their occurrence in open habitat on both large and small islands. Overall results support the habitat hypothesis and indicate that species distributions result from the interaction between habitat affinities and changes in habitat availability with island area.     

Plant extinction dynamics in an insular metacommunity

Changes in the composition of local communities through time (i.e. species turnover) is a common phenomenon in insular biology. However, the mechanisms promoting variation in species turnover, both among islands and among species, are poorly understood. In an effort to better understand the causes of variation in species turnover, we evaluated the colonization and extinction dynamics of plant populations on 18 small islands off the west coast of Canada. In 1997, we quantified total population sizes of 10 woody angiosperm species. A decade later, we resampled islands to test whether: 1) species turnover occurred, 2) colonization events were offset by extinction events, 2) variation in extinction rates among islands was associated with population sizes, average plant heights, island area, island isolation or each island's exposure to ocean-born disturbances, and 3) variation in extinction rates among species was associated with plant life history traits. Results showed that extinction events outnumbered colonization events, suggesting that the metacommunity is in 'disequilibrium'. Variation in extinction rates among islands was unrelated to island area and isolation. However, extinction rates increased with exposure to ocean-born disturbances and decreased with both initial population sizes and average plant heights. Species with thicker, tougher leaves (i.e. high leaf mass per area) were less prone to extinction than species with thinner, more papery leaves. Overall results indicate that species turnover is common and that it is generated primarily by extinction. Variation in extinction rates appears to result from an interaction between among-island effects (exposure, population size and plant stature) and among-species effects (leaf toughness), suggesting that ocean-born disturbances play a key role in determining metacommunity structure.     

Phenotypic evolution of dispersal-enhancing traits in insular voles

Evolutionary theory predicts that in metapopulations subject to rapid extinction–recolonization dynamics, natural selection should favour evolution of traits that enhance dispersal and recolonization ability. Metapopulations of field voles (Microtus agrestis) on islands in the Stockholm archipelago, Sweden, are characterized by frequent local extinction and recolonization of subpopulations. Here, we show that voles on the islands were larger and had longer feet than expected for their body size, compared with voles from the mainland; that body size and size-specific foot length increased with increasing geographical isolation and distance from mainland; and that the differences in body size and size-specific foot length were genetically based. These findings provide rare evidence for relatively recent (less than 1000 years) and rapid (corresponding to 100–250 darwins) evolution of traits facilitating dispersal and recolonization in island metapopulations.     

Neural processing of gustatory information in insular circuits

The insular cortex is the primary cortical site devoted to taste processing. A large body of evidence is available for how insular neurons respond to gustatory stimulation in both anesthetized and behaving animals. Most of the reports describe broadly tuned neurons that are involved in processing the chemosensory, physiological and psychological aspects of gustatory experience. However little is known about how these neural responses map onto insular circuits. Particularly mysterious is the functional role of the three subdivisions of the insular cortex: the granular, the dysgranular and the agranular insular cortices. In this article we review data on the organization of the local and long-distance circuits in the three subdivisions. The functional significance of these results is discussed in light of the latest electrophysiological data. A view of the insular cortex as a functionally integrated system devoted to processing gustatory, multimodal, cognitive and affective information is proposed.     

Connectivity, sustainability, and yield: bridging the gap between conventional fisheries management and marine protected areas

A substantial shift toward use of marine protected areas (MPAs) for conservation and fisheries management is currently underway. This shift to explicit spatial management presents new challenges and uncertainties for ecologists and resource managers. In particular, the potential for MPAs to change population sustainability, fishery yield, and ecosystem properties depends on the poorly understood consequences of three critical forms of connectivity over space: larval dispersal, juvenile and adult swimming, and movement of fishermen. Conventional fishery management describes the dynamics and current status of fish populations, with increasing recent emphasis on sustainability, often through reference points that reflect individual replacement. These compare lifetime egg production (LEP) to a critical replacement threshold (CRT) whose value is uncertain. Sustainability of spatially distributed populations also depends on individual replacement, but through all possible paths created by larval dispersal and LEP at each location. Model calculations of spatial replacement considering larval connectivity alone indicate sustainability and yield depend on species dispersal distance and the distribution of LEP created by species habitat distribution and fishing mortality. Adding MPAs creates areas with high LEP, increasing sustainability, but not necessarily yield. Generally, short distance dispersers will persist in almost all MPAs, while sustainability of long distance dispersers requires a specific density of MPAs along the coast. The value of that density also depends on the uncertain CRT, as well as fishing rate. MPAs can increase yield in areas with previously low LEP but for short distance dispersers, high yields will require many small MPAs. The paucity of information on larval dispersal distances, especially in cases with strong advection, renders these projections uncertain. Adding juvenile and adult movement to these calculations reduces LEP near the edges in MPAs, if movement is within a home-range, but more broadly over space if movement is diffusive. Adding movement of fishermen shifts effort on the basis of anticipated revenues and fishing costs, leading to lower LEP near ports, for example. Our evolving understanding of connectivity in spatial management could form the basis for a new, spatially oriented replacement reference point for sustainability, with associated new uncertainties.     

Allozyme variation in the endangered insular endemic Castilleja grisea

BACKGROUND AND AIMS: Genetic diversity in Castilleja grisea, an endangered, perennial herb endemic to San Clemente Island, California was investigated. Subsequent to the elimination of goats from the island in 1992, many populations of C. grisea have reappeared and have been increasing in size. METHODS: Nineteen populations were surveyed for their genotype at 19 allozyme loci. KEY RESULTS: At the taxon level, 57.9 % of loci are polymorphic with A(P) = 3.09 and H(E) = 0.137. Populations averaged 33.0 % polymorphic loci with A(P) = 2.43 and H(E) = 0.099. Most variation is found within rather than among populations (G(ST) = 0.128), although differentiation among populations is significant. Genetic identities range from I = 0.960 to I = 1.000 with mean I = 0.990. There is no significant relationship between genetic and geographic distance. Gene flow among populations is Nm = 2.50 based on private alleles and Nm = 1.70 based on F(ST). Outcrossing rates based on fixation indices average t = 1.01, indicating a primarily out-crossed mating system. CONCLUSIONS: The observed genetic variation is moderately high, unusually so for an insular endemic species, suggesting that C. grisea may not have lost substantial genetic variation during 150 years of overgrazing, and indicating that it is unlikely to be endangered by genetic factors.     

九江及周边地区183例头癣病原菌监测分析

目的 了解九江及周边地区近3年来头癣的类型及其病原菌分布情况.方法 采用回顾性方法对2008年5月～201 1年6月在九江学院附属医院皮肤科门诊就诊的183例头癣患者进行分析.结果 183例头癣患者年龄5个月～71岁,其中2 ～13岁患者164例(89.6％).白癣138例(75.4％)、脓癣28例(15.3％)、黑点癣17例(9.3％).镜检阳性144例(78.7％),培养阳性154例(84.2％).致病真菌主要为石膏样小孢子菌41株(26.6％)、须癣毛癣菌36株(23.4％)、红色毛癣菌33株(21.4％)、犬小孢子菌24株(15.6％)、紫色毛癣菌12株(7.8％).结论 九江及周边地区头癣患者以儿童为主,白癣发病率最高,石膏样小孢子菌占头癣病原菌首位,须癣毛癣菌、红色毛癣菌、犬小孢子菌分列第二、三、四位.