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Alien plant species and the re-associated introduced herbivore are well-suited for gaining insights into ecological interactions between species and their evolutionary consequences. Ambrosia artemisiifolia was introduced to Japan in the 1880s, and its specialist insect herbivore Ophraella communa was introduced in 1996. Here, we experimentally tested the hypothesis that O. communa mediates selection on flowering phenology of A. artemisiifolia. We grew plants from stored seeds collected in 1998, 2000, 2002, 2006 and 2009 and measured phenotypic selection on the first flowering date in a common garden where half of the plants were protected from herbivore damage. We observed stabilizing selection for flowering day in the absence of herbivores but directional selection toward earlier flowering when herbivores were present. Flowering time differed between seeds collected in different years, but these differences showed no clear trend and the flowering time fluctuated from year to year. We conclude that the introduced specialist herbivore mediates directional selection for earlier flowering, but that its introduction has not been associated with a change in flowering time. The lack of evolutionary change may be due to limited genetic variation or that selection by the herbivore is counteracted by selection through other selective agents in some years.

Understanding biotic and abiotic ecological processes that affect the invasion of alien plants is important for the successful management of terrestrial ecosystems. In this study, we investigated the effect of disturbances on invasive plants depending on whether soil biota is also disturbed. Disturbances that removed only aboveground biota did not affect the invasion condition, coexistence, or frequency after invasion, but did increase the growth rate of the invader when it was rare. In contrast, if disturbances affected both aboveground and belowground biota, the invader required a higher competitive ability compared to the situation of no disturbances, implying a suppression of alien species. As the probability of disturbance increased, the mean frequency of alien species either increased or decreased depending on its competitive ability. In conclusion, plant–soil feedback strongly affects the invasion of alien plants when the environment is subjected to physical disturbances.

While many plant species are considered threatened under anthropogenic pressure, it remains uncertain how rapidly we are losing plant species diversity. To fill this gap, we propose a Global Legume Diversity Assessment (GLDA) as the first step of a global plant diversity assessment. Here we describe the concept of GLDA and its feasibility by reviewing relevant approaches and data availability. We conclude that Fabaceae is a good proxy for overall angiosperm diversity in many habitats and that much relevant data for GLDA are available. As indicators of states, we propose comparison of species richness with phylogenetic and functional diversity to obtain an integrated picture of diversity. As indicators of trends, species loss rate and extinction risks should be assessed. Specimen records and plot data provide key resources for assessing legume diversity at a global scale, and distribution modeling based on these records provide key methods for assessing states and trends of legume diversity. GLDA has started in Asia, and we call for a truly global legume diversity assessment by wider geographic collabora- tions among various scientists.

SummaryIn 2011 the Black-faced Spoonbill Platalea minor census recorded a 22% drop in numbers from 2010, particularly at the known large coastal wintering sites. During this period, we discovered two new inland wintering sites for the species using satellite telemetry data, one located in China, where the individual followed the Yangtze river as far as Wuhan (500 km inland), and the other across the Vietnam-Cambodia border (70–200 km inland). Long periods of concentrated use of various freshwater habitats were in evidence for these two tagged individuals (China: 79 days, Vietnam/Cambodia: 91 Days) and in the latter case visual confirmation indicated a larger group of at least five individuals. The importance and potential of inland freshwater environments is highlighted towards the further conservation of the recovering population.

A new species, Callicarpa bachmaensis Soejima & Tagane, sp. nov., is described and illustrated from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species has a characteristic liana habit, white corolla, and narrowly elliptic to narrowly lanceolate, entire, occasionally subequal leaves, by which it is clearly distinguished from the other previously known species of this genus.

A new species, Popowia bachmaensis Ngoc, Tagane & Yahara, sp. nov. is described from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species is morphologically similar to Popowia pisocarpa (Blume) Endl. ex Walp., but can be readily distinguished from it by its lower stems, smaller leaves, shorter flowering pedicels, shorter carpels, longer sepals and inner petals. A detailed description, comprising illustrations, and supplemented with DNA barcodes of the two regions of rbcL and matK, are provided.

East Tiaoxi River is one of the largest inflowing rivers into Taihu Lake, and the fish fauna in the river is poorly understood. In the present study, an extensive survey of fish was conducted in October and November 2009, May and September 2010 and May 2011 covering a total of 55 sites along the whole river. A total of 84 freshwater fish species belonging to 8 orders, 18 families and 52 genera have been recorded. Among these are 35 species endemic to China, and 3 newly recorded exotic species. The fish composition varies greatly from headwaters to downstream. Based on cluster analysis with presence-absence data, the East Tiaoxi River is divided into four regions, specifically, the upper reach, middle-up reach, middle reach and lower reach. It is observed that species richness and the proportion of omnivorous species increased from upstream to downstream while the proportion of invertivorous species decreased consequently. Habitat alteration, overfishing, pollution and inland navigation adversely affect the fish diversity and ecosystem functioning in the East Tiaoxi River. To protect fish diversity more effectively in the area, the conservation of fish biodiversity in the North Tiaoxi River and Middle Tiaoxi River should be considered as a priority. Meanwhile, shallow zones or backwater areas should be created in the middle-lower reaches. Furthermore, river restoration, in terms of habitat creation, should be considered to protect the structure and diversity of fish communities, halt the progressive deterioration of freshwater ecosystems and sustain a valuable ecological resource for humans.

In this paper, a GIS server system application has been developed using the ArcGIS technology for supporting biodiversity observation study. Survey database of China as for example has been used to investigate the effectiveness of the GIS server system. As a result, the developed server application is considerably valuable for creating, sharing and utilizing biodiversity information.

The spatial and temporal variations of the fish assemblages in mountain streams of China are poorly understood. The relationships between the fish assemblage and selected habitat features were examined in the North Tiaoxi River, one of headwaters of Taihu Lake. A total of 3,348 individuals belonging to 5 orders, 11 families, 25 genera and 34 species were collected including 33 native species and one invasive species. Among those, about 20 species were endemic to China. Non-metric Multidimensional Scaling (NMDS) was applied to compare fish assemblage structures from upstream to downstream during four seasons. Species assemblages differed along the stream continuum, but there was little apparent change associated with the seasons. Species richness and Shannon-Weaver index (H′) tended to increase along the stream continuum from the upstream to downstream and the proportion of invertivorous fish tended to significantly decrease along the continuum with a parallel significant increase in the percentage of omnivores. Fish assemblages were significantly related to both water quality and habitat structure variables. Canonical Correspondence Analysis ordinations (CCA) revealed that 6 of the 14 selected environmental variables had significant relationships with the fish assemblage such as distance to source, stream width, altitude, pH, water depth, and water velocity and different sampling sites were associated with different environmental variables in different seasons. The main differences in fish assemblage structure and diversity within the whole watercourse are probably related to large-scale factors such distance to source, altitude and stream width. Differences of instream characteristics are likely to be caused by natural variability of the ecosystems but also, in some case, by anthropogenic influence like human settlements, agriculture and river embankment and pollution from small factory.

Floral traits such as color and size are highly diversified in lilies, but their adaptive significance remains uncertain. In the present study, we compared pollination processes between Lilium japonicum var. abeanum and var. japonicum to clarify how the two varieties are adapted to different pollinators. Lilium japonicum var. japonicum is known to be pollinated by moths, and we hypothesized from its flower traits that var. abeanum is pollinated by diurnal insects. Using waterproof digital cameras set to a recording interval of 10–30 s, we recorded flower visitors for 7–9 flowers of var. japonicum and 4–6 flowers of var. abeanum over 24-h periods. We also recorded the number of versatile (T-shaped) and rigid (I-shaped) anthers per flower. For var. abeanum, we observed flowers at 05.00 and 17.00 hours to determine flower opening time and measured the intensity of floral scent using a metal-oxide semi-conductor odor sensor. Both diurnal and nocturnal insects visited flowers of the two varieties, but visitation of diurnal insects was more frequent in var. abeanum. Anthers of var. abeanum are usually rigid, as in many bee-pollinated flowers, whereas those of var. japonicum are mostly versatile. Although flowers of var. japonicum are known to open in the evening, 32% of the flowers of var. abeanum started to flower during the day. Lilium japonicum var. abeanum emitted scent at night, with a maximum intensity at 20.00 hours, just as in var. japonicum. These findings suggest that the floral traits of the two varieties are adapted to the different relative availabilities of nocturnal versus diurnal pollinators. The flower of var. abeanum is more adapted to diurnal pollinators, but retains adaptations to nocturnal pollinators, particularly with regard to its scent.

In nature, spatiotemporally dynamic coevolutionary processes play major roles in the foundation and maintenance of biodiversity. Here, we examined the arms race coevolution involving a seed-eating weevil with a long snout and its camellia plant host with a thick fruit coat (pericarp) throughout the marked climatic gradient observed across the Japanese islands. Results demonstrated that female weevils, which bored holes through camellia pericarps to lay eggs into seeds, had evolved much longer snouts than males, especially in areas in which Japanese camellia pericarps were very thick. The thickness of the plant pericarp was heritable, and the camellia plant evolved a significantly thicker pericarp on islands with the weevil than on islands without it. Across populations with weevils, resource allocation to plant defense increased with increasing annual mean temperature or annual precipitation, thereby geographically differentiating the evolutionary and ecological interactions between the two species. Given that the coevolutionary relationship exhibited appreciable variation across a relatively small range of annual mean temperatures, ongoing global climatic change can dramatically alter the coevolutionary process, thereby changing the ecological interaction between these species.

A framework for exploring regional-scale trade-offs among ecosystem services and biodiversity protection has been established for some time, and it is clear that optimizing these trade-offs provides a strategy to address targets for a reduced rate of biodiversity loss. Recent trade-off studies have highlighted the need for better biodiversity measures, to complement measures of ecosystem services. Biodiversity typically has been linked in this context to existence and other non-use values. We argue that biodiversity will have a stronger role in such trade-off analyses if measures of biodiversity better reflect additional current and future services. These ‘evosystem services’ have been, and, if we are careful, can continue to be provided by the evolutionary process. Some services have been provided through evolution operating in the past, and a phylogenetic diversity measure can help us to quantify these current and potential future benefits derived from the tree of life. Furthermore, a variety of evosystem services are delivered through ongoing contemporary evolution, and value should therefore be placed on the maintenance of healthy evosystems. We argue that the concept of evosystem services could be useful as a complement to the traditional concept of ecosystem services. Together, these reflect a fuller range of the services supported by biodiversity, and thereby provide a sounder basis for conservation planning and decision-making.

Genetic elements determine phenotypes of organisms by interacting with environments. Despite genetic diversity within and between species being the fundamental basis of biological diversity, its contribution has been long neglected in biodiversity studies. This situation is rapidly changing as quantification of genetic diversity, from intraspecific up to the ecosystem level, has become more accessible owing to the development of next-generation sequencing technologies (NGSTs). Whole-genome sequencing techniques provide two specific approaches for accessing genetic diversity at large scales: metagenomics (environmental genomics) and EST (Expressed Sequence Tag) comparisons. The former has been applied successfully in the profiling of different microbial biomes, and it is particularly interesting in understanding their ecosystem structure and function. The latter is particularly useful in the studies of adaptation and the assessment of functional traits. Unquestionably, advances in the genomic sciences combined with a new generation of ecological and evolutionary science will boost new approaches to global and local assessments of biodiversity changes, and more importantly, will surely reframe the questions we are asking in biodiversity science.

Erythroxylum calyptratum, sp. nov. (Erythroxylaceae), from Mt. Fansipan, Hoang Lien National Park, Lao Cai Province, northern Vietnam, is newly described. The new species is characterized by thinly chartaceous leaves with 2–3 mm long petiole, 1–3 flowered inflorescences, downward facing white flowers, well-developed petal appendages (1/3–1/2 length of petals) and entirely free 3 styles. A description, illustrations, DNA barcodes of rbcL and matK and a key to the species of Erythroxylum in Indochina are provided.

Lecanorchis Blume (1856: 188) comprises about 30 species of mycoheterotrophic orchids (Seidenfaden 1978, Hashimoto 1990, Szlachetko & Mytnik 2000, Govaerts et al. 2017) characterized by having numerous, long, thick, horizontal roots produced from a short rhizome, presence of a calyculus (i.e. a cup-like structure located between the base of the perianth and apex of the ovary) and an elongate column with a pair of small wings on each side of the anther (Seidenfaden 1978, Hashimoto 1990). The genus is distributed across a wide area including China, Korea, India, Indonesia, Japan, Laos, Malaysia, New Guinea, Pacific islands, the Philippines, Taiwan, Thailand and Vietnam (Seidenfaden 1978, Hashimoto 1990, Pearce & Cribb 1999, Szlachetko & Mytnik 2000, Averyanov 2011, 2013).

Two new species of Annonaceae, Monoon namkadingense and Neo-uvaria laosensis, from Nam Kading National Protected Area, Bolikhamxay Province, Central Laos, are described and illustrated. DNA barcodes of rbcL and matK, vernacular name and primary conservation assessment are also provided. Both species are considered to be endemic to this area and categorized as Endangered (EN). The distribution of Neo-uvaria laosensis represents northern limit of distribution range for the genus.

A new species of Begonia (Begoniaceae), B. namkadingensis, is described. This species was collected on moist mossy limestone rocks in the Nam Kading National Protected Area in central Laos during our field survey in 2017. The species resembles B. pteridiformis, which is endemic to Peninsular Thailand, but can be distinguished by its smaller habit, fewer and smaller leaves, less hairy stems and leaves, narrower inner dorsal tepal of pistillate flowers, fewer stamens, and smaller fruits.

The genus Thismia Griffith (1844: 221) of the tribe Thismieae, Burmanniaceae sensu APG IV (2016) or Thismiaceae of other authors, represents one of the most species-rich mycoheterotrophic genera and consists of more than 60 species (Jonker 1948, Merckx 2008). Considering that the majority of these species were collected only once (Jonker 1948), and that many new species have recently been discovered, especially from various Southeast Asian countries (e.g., Tsukaya & Okada 2012, Dančák et al. 2013, Nuraliev et al. 2014, 2015, Truong et al. 2014, Chantanaorrapint & Sridith 2015, Li & Bi 2013, Hroneš et al. 2015, Tsukaya et al. 2017, Suetsugu et al. 2017), many more undescribed species are probably still hidden in the tropical rain forests of Southeast Asia.

Zanthoxylum ailanthoides Siebold & Zucc. is one of the most frequently encountered pioneer trees in Japanese warm-temperate evergreen oak forests. Our previous study in one region of Japan suggested high levels of population differentiation and putative natural selection acting on one of the nuclear loci analyzed. Here, we extend our analysis to study the genetic structure of 10 populations of Z. ailanthoides across Japan using 9 simple sequence repeat (SSR) loci for a better understanding of its genetic structure. First, the southernmost population (Kagoshima) in the samples was found to have the highest genetic diversity, suggesting there was a glacial refugium at or near the location of the population. Second, relatively strong genetic differentiation was found among populations, and there was a positive correlation between genetic distances and geographic distances (Mantel test; P < 0.001). Based on this information, we analyzed nucleotide variation at the putatively selected locus homologous to the gene encoding the ADP-glucose pyrophosphorylase large subunit (agpL). Despite the strong genetic differentiation among populations suggested by the SSR loci, the agpL locus was monomorphic in almost all populations analyzed. The results of this study strongly supported the possibility of a selective sweep at or near the agpL locus.

Herein, Mussaenda recurvata, a new species from Hon Ba Nature Reserve, southern Vietnam, is described and illustrated. This species is morphologically similar to M. longipetala, distributed from southern China to northern Vietnam, in having recurved stipules and densely pilose and puberulent hairs throughout, but differs in its strongly recurved calyx lobes, a shorter corolla tube, and ovate corolla lobes. The species is morphologically heterostylous and it appears to be functionally dioecious. An updated key to Mussaenda species in Vietnam, Laos, and Cambodia is also provided.

The capacity of ecosystems to deliver essential services to society is already under stress. The additional stresses imposed by climate change in the coming years will require extraordinary adaptation. We need to track the changing status of ecosystems, deepen our understanding of the biological underpinnings for ecosystem service delivery and develop new tools and techniques for maintaining and restoring resilient biological and social systems. We will be building on an ecosystem foundation that has been radically compromised during the past half century. Most rivers have been totally restructured, oceans have been severely altered and depleted, coral reefs are near the tipping point of disappearing as functional ecosystems, over half of the land surface is devoted to livestock and crop agriculture, with little consideration for the ecosystem services that are being lost as a consequence, some irrevocably so. We have already seen many regime shifts, or tipping points, due to human activity, even before the onset of measurable climate change impacts on ecosystems. Climate change, caused mainly by anthropogenic greenhouse gas emissions, will disrupt our ecosystem base in new ways. Already we are seeing widespread signs of change. Species behaviors are altering and disrupting mutualisms of long standing. We are seeing extinctions within vulnerable habitats and conditions where migrations are necessary for survival but where often there are no pathways available for successful movement in the fragmented world of today. These challenges represent an extraordinary threat to society and a call for urgent attention by the scientific community.

In many gynodioecious species, sex determination involves both cytoplasmic male-sterility (CMS) genes and nuclear genes that restore male function. Differences in fitness among genotypes affect the dynamics of those genes, and thus that of gynodioecy. We used a molecular marker to discriminate between hermaphrodites with and without a CMS gene in gynodioecious Raphanus sativus. We compared fitness through female function among the three genotypes: females, hermaphrodites with the CMS gene and those without it. Although there was no significant difference among the genotypes in seed size, hermaphrodites without the CMS gene produced significantly more seeds, and seeds with a higher germination rate than the other genotypes, suggesting no fitness advantage for females and no benefit to bearing the CMS gene. Despite the lack of fitness advantage for females in the parameter values we estimated, a theoretical model of gynodioecy shows it can be maintained if restorer genes impose a cost paid in pollen production. In addition, we found that females invest more resources into female reproduction than hermaphrodites when they become larger. If environmental conditions enable females to grow larger this would facilitate the dynamics of CMS genes.

Similar distribution ranges shared by closely related plant species may have been shaped through different migration histories if those species have differing habitat preference. To test this hypothesis, phylogeographical patterns and population genetic structures were compared between two sister Viola species: Viola eizanensis preferring woodland and V. chaerophylloides var. sieboldiana preferring grassland, both being native to the Japanese Archipelago. Amplified fragment length polymorphism (AFLP) was used for phylogenetic reconstruction, together with Bayesian ancestry analysis, AMOVA, analysis of genetic diversity statistics, and analysis of the relative contribution of each population to total diversity. The results indicated that V. eizanensis had two distinct lineages occurring in the western and eastern part of Japan, but such lineages are not distinct in V. chaerophylloides var. sieboldiana. Both species exhibited the low genetic diversity and high between-population differentiation typical of selfing plants. In V. chaerophylloides var. sieboldiana, one particular population made a significantly higher contribution to the total heterozygosity (H T), whereas in V. eizanensis, no population was identified as making a particularly higher contribution to H T. These findings suggest that V. eizanensis had been isolated in two large glacial refugia, whereas populations of V. chaerophylloides var. sieboldiana were restricted to a single small refuge. Different light requirements between these two closely related species probably caused these differing responses to climatic change during the last ice age.

The good genes hypothesis and the genetic compatibility hypothesis are the two main hypotheses that focus on the genetic benefit that a female can gain through her choice of a mate. We tested the two hypotheses on extra-pair mating in the great tit, Parus major. We found that female great tits choose males on the basis of breast stripe width, which is in accordance with the good genes hypothesis. Although females chose less related extra-pair males, the evidence for female choice for compatible males was overall weak. However, our data suggest a post-copulatory mechanism of inbreeding avoidance. The observed individual inbreeding coefficient, F, was similar for within-pair offspring (WPO) and extra-pair offspring (EPO). The observed individual F of WPO was lower than the expected individual F, whereas the observed F of EPO was similar to what was expected. These results highlight the importance of processes after copulation for the outcome of female mate choice. Our study shows that in a system with apparent pre-copulatory female choice for good genes, a post-copulatory mechanism may still promote the production of offspring that carry compatible genes.

Differences in demographic history, life-history traits, and breeding systems affect nucleotide variation patterns. It is expected that shade-intolerant pioneer tree species have different patterns of genetic polymorphism and population structure than climax species. We studied patterns of nucleotide polymorphism at four putative starch pathway loci (agpSA, agpSB, agpL, and GBSSI) in Zanthoxylum ailanthoides, a shade-intolerant pioneer tree species that occupies forest gaps in warm-temperate forests of East Asia. Genetic diversity was lower within each population than among populations, and differentiation among populations was high across the loci (F(ST) = 0.32-0.64), as expected from the insect-pollinated breeding system and the metapopulation structure of this pioneer species. Numbers of haplotypes were smaller than those expected from the observed numbers of segregating sites. Single haplotypes accounted for more than 47% of all the sampled genes at the respective loci. These variation patterns were incompatible with neutral predictions for populations of a finite island model. Complex population dynamics, such as bottleneck and/or admixture, in the history of this pioneer tree species might have resulted in the observed patterns of genetic variation and population structure, which are different from those of climax wind-pollinated tree species, such as conifers. In contrast to the other loci investigated in this study, agpL showed nearly no variation in Z. ailanthoides (one singleton only), but there was some extent of variation in a closely related species, Zanthoxylum schinifolium. This suggests possibly a recent selective sweep at or near the locus in Z. ailanthoides.

Reproductive failure of backcross could play important roles in determining the evolutionary outcome of hybridization. However, such studies have been somewhat fewer than those of the F1-producing cross and F1 x F1 cross. We conducted hand-pollination backcross experiments using Hemerocallis fulva, H. citrina, and their F1 hybrids. Seed set per flower of the backcrosses reduced to about 50% of the control cross, irrespective of ovule parent species. This symmetrical seed set reduction on the backcross might be caused by the death of backcross embryo as a result of Dobzhansky-Muller incompatibility by recessive alleles.

Chromosome numbers were determined from microsporocytes (meiotic counts) and root-tip cells (mitotic counts) in 201 collections of 51 genera and 119 specific and infraspecific taxa belonging to nine tribes of Asteraceae and Acicarpha spathulata R. Br. of Calyceraceae from Australia, Bolivia, Brazil, Chile, Mexico, and the United States. These include the first reports and new numbers for the basal members of the Barnadesieae and Mutisieae. First reports are provided for 45 taxa, including five genera, Dasyphyllum HBK (2n = 54), Dithyrostegia A. Gray (2n = 14), Epitriche Turcz. (2n = 10), Revealia R. M. King & H. Rob. (2n = 22), and Stifftia J. C. Mikan (2n = 54). In addition, new chromosome numbers are established at the generic level in the genera Barnadesia Mutis (2n = 54), Eremanthus Less. (2n = 34, 30), Macvaughiella R. M. King & H. Rob. (2n = 24), and Trichocline Cass. (2n = 38), and in 12 additional species. Remaining counts augment and agree with previously reported determinations. The base chromosome numbers of Calyceraceae and Asteraceae are discussed in published records and our original counts.

Lysimachia tashiroi Makino (Myrsinaceae) is an endangered perennial herb growing in moist places along riverbanks in restricted localities of Kyushu, Japan. The largest population known to date is located in Gokayama and is under threat of extinction because of the planned construction of a dam. To develop a conservation plan of the riverbank population of L. tashiroi in Gokayama, we examined genetic variation in the population using amplified fragment length polymorphisms (AFLPs). A related and widespread species, L. japonica , was included in the analysis. A total of 733 AFLP fragments were obtained from 73 accessions. An AMOVA for L. tashiroi showed that within-population and between-population variability were 62% and 38%, respectively. In addition, genetic variability was higher in L. tashiroi than in L. japonica . These results are unexpected because plants of L. tashiroi propagate vegetatively and seed fertility is very low in the Gokayama population. Based on our findings, we suggest that as many genets as possible should be transplanted to appropriate habitats neighboring the dam construction area.

As a basis for comparative studies of mating systems, we estimated genetic diversities and inbreeding coefficients for six perennial species of Ainsliaea and two shrubby species of Pertya (Asteraceae). These related species are known to vary from frequent cleistogamy to xenogamy by bumblebee pollination, and we examined allozyme variation in these species to describe mating system variation in further detail. Significant heterozygote deficit was found in five species, while no heterozygote deficit was found in three species. A cleistogamous species showed no genetic polymorphism. Multilocus average of inbreeding coefficients among seven species ranged from −0.12 to 0.78. These findings indicated that related species can vary from predominant selfers to predominant outcrossers under perennial life cycles.

The resource allocation models for the evolution of a mixed production of cleistogamous and chasmogamous flowers were tested in four natural populations of Impatiens noli-tangere L. When we incorporated the estimated parameter values into our basic model, under the assumption that the environmental conditions did not change through the reproductive season, the model predicted the obligate chasmogamy in all four populations. However, including the fluctuation of the fertility of chasmogamous flowers in the model, the seasonal switching of chasmogamous and cleistogamous flower production becomes an evolutionary stable strategy, which explains the reproductive behavior of the individuals in two populations. Only after the relationship between the geitonogamy of chasmogamous flowers and the number of chasmogamous flower production was considered in the model did the simultaneous production of both of the dimorphic flowers become an evolutionary stable strategy. Further, the complete model clarifies the reproductive behavior of the individuals in the other two populations.

In gynodioecious plant populations, sex determination often involves both cytoplasmic male-sterility (CMS) genes and specific nuclear genes that restore male function. How gynodioecy is maintained under the joint dynamics of CMS and restorer genes remains controversial. Although many theoretical models deal with interactions between CMS genes and restorer genes with sexual phenotypes and predict changes in their frequencies, it is difficult to observe the frequencies because no molecular markers have been established for either CMS or restorer genes in well-studied gynodioecious plants. This is the first report of the frequency of a CMS gene determined using a molecular marker in natural populations of a gynodioecious plant. Using a set of CMS gene-specific polymerase chain reaction primers, we compared female and CMS gene frequencies in 18 natural populations of Raphanus sativus. Female frequency was relatively low, ranging from 0 to 0.21. In contrast, the CMS gene frequency was highly variable among populations, ranging from 0 to 1. Estimated restorer gene frequency seemed less variable than observed CMS gene frequency, probably due to higher gene flow than in the CMS gene. Genetic drift may play a role in maintaining high variability of the CMS gene, although other possibilities are not excluded.

During the last decade, evidence from a number of studies has suggested systematic deviations from a 1 : 1 primary sex ratio in birds, in spite of the fact that birds have chromosomal sex determination systems; the mechanism of sex allocation is not fully understood. However, it still remains uncertain whether adaptive manipulations of primary sex ratio occur, especially in Parus species. We studied sex ratio variation in the Varied Tit Parus varius , which is a socially monogamous species similar to the Great Tit P. major and the Blue Tit P. caeruleus . In total, 362 chicks that hatched from 72 broods over 3 years were sexed. Of all nestlings, 51.9% (188/362) were male. The nestling sex ratio did not differ significantly from unity. However, the proportion of sons in each brood was significantly and positively related to the father’s tarsus length. This corresponds with our predictions, given that larger males have higher resource holding potential if tarsus length is a heritable character between fathers and sons.

The Red Data Book of Japanese Vascular Plants is based on their risk of extinction. In order to construct the list, 2000 taxa were evaluated using population data and rates of decline for approximately 4400 grids, each of approximately 100 km(2). This database can be used to estimate the impact of human activity on a threatened plant's risk of extinction. In order to evaluate extinction risks and apply the evaluation to conservation actions, the discount mean time to extinction is defined as a measure of extinction risk, where the present value of a species' persistence in the future decreases exponentially. The rate of decrease has to be much less than the rate of economic discounting, in order to realize intergenerational sustainability. Increases of the inverse, and logarithm, of the discount mean time to extinction are considered measures of the extinction risk. We applied these measures to an environmental impact assessment for the Japanese World Exposition that is to be held in 2005. Development will have a greater impact on threatened Salvia species than it will on star magnolia, Magnolia tomentosa, which has been conserved by changing the site plan.

Summary 1. Patterns of pollinator responses to variation in floral display size have significance for pollen flow among plants. Here we test a theoretical model for explaining such patterns by simultaneously assessing bumble bee behaviour and nectar availability in two native stands of Cirsium purpuratum with different spatial densities. 2. A bumble bee ( Bombus diversus ) foraging on a plant remembered and avoided only one or two flower heads that it had probed before, so that the flower-head revisitation rate increased as it stayed longer on a plant. Moreover, the revisitation rate increased less rapidly on larger displays. 3. The number of heads probed per plant increased less than proportionally with display size, and this increase was smaller at higher plant density. This pattern is consistent with our expectation that a bee leaves a plant when the cost of flower-head revisitation exceeds that of interplant movement. However, bees left plants slightly earlier than predicted. 4. As predicted, the visitation rate of bees per plant showed a decelerated increase with floral display size, and this increase was greater at higher plant density. 5. As a result of these complementary changes in the number of heads probed per plant and visitation rate per plant across plant densities, nectar rewards per head were equalized among displays (an ideal free distribution was achieved).

In order to clarify the temporal variation of flock size, we examined factors that cause the temporal variation of foraging flock size in a wintering population of the Yellow-throated bunting (Emberiza elegans). We conducted field observations to examine whether the flock size varies greatly and whether non-random associations between individuals exist. We confirmed that flock size varied greatly and some individuals showed non-random associations with other flock members. Then, we carried out computer simulations that assume stochastic risky situation, the condition of hunger level and non-random associations between individuals. In the simulation, the condition of hunger level caused the variation of flock size. However, the distribution of flock size differed from observed ones. When the condition of non-random association was added to the simulation, the variation of flock size became large and the distribution of flock size was similar to that of the observed one. In wintering flocks of Yellow-throated bunting, each individual attempts to forage in an optimal flock size. However, if they are extremely starved, it is suggested that they adopt a conditional strategy to join a flock independently of the flock size to acquire the energy necessary for survival. Simultaneously, they may decide to forage under the effect of non-random association between individuals.

To elucidate the evolutionary dynamics of rDNA site number in polyploid plants, we determined 5S and 18S-5.8S-26S rDNA sites for ten species of Sanguisorba (2n=14, 28, 56) and a single species of each of three outgroup genera, Agrimonia (2n=28), Rosa (2n=14), and Rubus (2n=14) by the fluorescence in situ hybridization (FISH) method. We also estimated phylogenetic relationships among these species using matK chloroplast DNA (cpDNA) sequences, and reconstructed the evolutionary history of rDNA site number based on the maximum parsimony method. The 2n=14 and 2n=28 plants of all genera except Rosa carried two 5S rDNA sites, whereas Rosa and 2n=56 plants carried four sites. The 2n=14 plants had two 18S-5.8S-26S rDNA sites, whereas Sanguisorba annua and 2n=28 plants had four or six sites. Phylogenetic analysis showed that polyploidization from 2n=14 to 2n=28 has occurred once or three times in Sanguisorba and Agrimonia. The 5S rDNA sites duplicated during each ancestral polyploidization were evidently lost after each polyploidization. However, the duplicated 18S-5.8S-26S rDNA sites were all conserved after each polyploidization. Thus, the duplicated 5S rDNA sites tend to have been eliminated, whereas those of 18S-5.8S-26S rDNA tend to have been conserved in Sanguisorba. In the most parsimonious hypothesis, 2n=14 in S. annua is a secondary, putatively dysploid state, reduced from 2n=28.

Kinoshita, M., Kasuya, E. and Yahara, T. 2002. Effects of time-dependent competi-tion for oviposition sites on clutch sizes and offspring sex ratios in a fig wasp. –Oikos 96: 31–35.Fig wasps have been known as one of the best-documented examples of female-biased sex ratio predicted from the local mate competition (LMC) theory. However,observed sex ratios appear more female-biased than predicted. Before a close matchbetween theory and observation can be claimed, the number and sex ratio ofoffspring left by each foundress in a multi-foundress syconium need to be determined.We examined the clutch size and sex ratio of individual females of the pollinator figwasp

A new species, Wikstroemia bokorensis (Thymelaeaceae), from Bokor National Park, Kampot Province, Cambodia, is described and illustrated. This species is morphologically most similar to W. nutans distributed in southern China and Vietnam, but differs in having pubescent branches and leaves, smaller anthers, a single disk scale, and glabrous ovary. DNA barcodes of ITS, rbcL, trnT-F, rps16, and rpl16 regions for the new species are also provided.

Here we describe a new species of the mycoheterotrophic genus Thismia (Thismiaceae), T. brunneomitroides, discovered during a botanical survey in Khao Luang National Park, Peninsular Thailand. Thismia brunneomitroides resembles Thismia brunneomitra from Brunei Darussalam in that both species possess inner tepal lobes that are connate to form a mitre with three projections at the apex and large lateral appendage of the connective. However, it differs in having ivory flowers with twelve pale orange to brownish orange vertical stripes on the perianth tube and slightly dentate lateral appendage of the connective which does not exceed apical part of the connective. Descriptions, illustrations and a key to the 13 species of Thismia in the Thai-Malay Peninsula are provided.

Isolation mechanisms that prevent gene flow between populations prezygotically play important roles in achieving speciation. In flowering plants, the nighttime flowering system provides a mechanism for isolation from diurnally flowering species. Although this system has long been of interest in evolutionary biology, the evolutionary process leading to this system has yet to be elucidated because of the lack of good model species. However, the genetic mechanisms underlying the differences in flowering times and the traits that attract pollinators between a pair of diurnally and nocturnally flowering species have recently been identified in a few cases. This identification enables us to build a realistic model for theoretically studying the evolution of a nocturnally flowering species. In this study, based on previous experimental data, we assumed a model in which two loci control the flowering time and one locus determines a trait that attracts pollinators. Using this model, we evaluated the possibility of the evolution of a nocturnally flowering species from a diurnally flowering ancestor through simulations. We found that a newly emerging nighttime flowering flower exhibited a sufficiently high fitness, and the evolution of a nocturnally flowering species from a diurnally flowering species could be achieved when hybrid viability was intermediate to low, even in a completely sympatric situation. Our results suggest that the difference in flowering time can act as a magic trait that induces both natural selection and assortative mating and would play an important role in speciation between diurnally and nocturnally flowering species pairs.

Although many people have expressed alarm that we are witnessing a mass extinction, few projections have been quantified, owing to limited availability of time-series data on threatened organisms, especially plants. To quantify the risk of extinction, we need to monitor changes in population size over time for as many species as possible. Here, we present the world's first quantitative projection of plant species loss at a national level, with stochastic simulations based on the results of population censuses of 1618 threatened plant taxa in 3574 map cells of ca. 100 km2. More than 500 lay botanists helped monitor those taxa in 1994-1995 and in 2003-2004. We projected that between 370 and 561 vascular plant taxa will go extinct in Japan during the next century if past trends of population decline continue. This extinction rate is approximately two to three times the global rate. Using time-series data, we show that existing national protected areas (PAs) covering ca. 7% of Japan will not adequately prevent population declines: even core PAs can protect at best

The article discusses the significant role of biodiversity in the evolution. Topics discussed include importance of applying evolutionary principles in conservation and human well-being, fundamental relevance of evolution in the production, maintenance, and future of biodiversity and biodiversity arises from the approach that treats groups of taxa with similar traits as a significant functional unit.

Background The margins of a species’ range might be located at the margins of a species’ niche, and in such cases, can be highly vulnerable to climate changes. They, however, may also undergo significant evolutionary changes due to drastic population dynamics in response to climate changes, which may increase the chances of isolation and contact among species. Such species interactions induced by climate changes could then regulate or facilitate further responses to climatic changes. We hypothesized that climate changes lead to species contacts and subsequent genetic exchanges due to differences in population dynamics at the species boundaries. We sampled two closely related Rubus species, one temperate (Rubus palmatus) and the other subtropical (R. grayanus) near their joint species boundaries in southern Japan. Coalescent analysis, based on molecular data and ecological niche modelling during the Last Glacial Maximum (LGM), were used to infer past population dynamics. At the contact zones on Yakushima (Yaku Island), where the two species are parapatrically distributed, we tested hybridization along altitudinal gradients. Results Coalescent analysis suggested that the southernmost populations of R. palmatus predated the LGM (~20,000 ya). Conversely, populations at the current northern limit of R. grayanus diverged relatively recently and likely represent young outposts of a northbound range shift. These population dynamics were partly supported by the ensemble forecasting of six different species distribution models. Both past and ongoing hybridizations were detected near and on Yakushima. Backcrosses and advanced-generation hybrids likely generated the clinal hybrid zones along altitudinal gradients on the island where the two species are currently parapatrically distributed. Conclusions Climate oscillations during the Quaternary Period and the response of a species in range shifts likely led to repeated contacts with the gene pools of ecologically distinct relatives. Such species interactions, induced by climate changes, may bring new genetic material to the marginal populations where species tend to experience more extreme climatic conditions at the margins of the species distribution. Electronic supplementary material The online version of this article (doi:10.1186/s12862-014-0209-9) contains supplementary material, which is available to authorized users.

Organizing regional networks of biodiversity observation is crucial to establishing the knowledge base for biodiversity conservation. Here we review the history and activities of AP-BON (Asia-Pacific Biodiversity Observation Network), an active network of biodiversity observation in the Asia-Pacific region. AP-BON was organized in 2009, 1 year earlier than CBD COP 10 in 2010, and developed through four workshops and additional related meetings. The most recent, the fourth, AP-BON workshop was held in 2011, wherein implementation for 2012–2015 was confirmed. Major activities planned for 2012–2015 are (1) editing and networking the national biodiversity outlook, (2) publication of additional AP-BON books, (3) promotion of collaborative projects, (4) development of a shared database, and (5) capacity building. As for the third activity, implementation for 2012–2015 has been developed in five working groups (WGs). WG 1 (genetics/phylogenetic diversity) is promoting genetic diversity assessment to contribute to a GEO BON genetic diversity report. WG 2 is carrying out plant diversity assessments using a standardized transect method in Southeast (SE) Asian countries. WG 3 (terrestrial ecosystem) is developing (1) networks of in situ monitoring and a database on terrestrial ecosystems, (2) a database on function and services of terrestrial ecosystems, and (3) maps of biodiversity, function, and ecosystem services. WG 4 (freshwater) is monitoring Asian freshwater biodiversity at the genus, species, and ecosystem levels, focusing on fish and aquatic plants. WG 5 (marine) is developing a database to share biodiversity information and collecting data on kelp forests, seagrass meadows, coral reefs, pelagic water, and the deep sea. An important role of AP BON is to network these projects by providing opportunities for communication and interaction, developing tools for data collection, sharing, analysis, and synthesis, and carrying out assessments helpful for improving ecosystem management and sustainable use of biodiversity.

Cytogeographical studies have revealed the distribution of sexual diploids and agamospermous polyploids of Stevia ovata and four related species: Stevia nepetifolia, Stevia oligophylla, Stevia origanoides and Stevia triflora in Mexico. These species are distributed mainly in the temperate and subhumid montane region. Agamospermous triploids are the forms most abundantly and widely distributed geographically in each of the five species. Diploids occur in low frequencies except in S. origanoides. For the five species, diploids are restricted mainly to the temperate montane ranges of the south-western Pacific side of Mexico, but they also occur sporadically in the relatively isolated areas from Oaxaca to Durango, Mexico D. F. and Nuevo Leon. Although the distribution of the temperate forests must have moved southward and northward following climatic fluctuations, even in the lower latitudes of Mexico, the largely stable temperate vegetation could have been maintained along the Y-shaped montane ranges (Sierra Madre del Oriental, Sierra Madre del Occidental, Sierra Madre del Sur and the Trans-Mexico Volcanic Belt) and have provided some refuge areas. The present distribution ranges of sexual diploids of some species of Stevia in Mexico indicate that diploids were not restricted to a single refuge during the last ice age.

Thirteen new species of the genusStevia are described and illustrated from Mexico:S. chilapensis, S. coahuilensis, S. crassifolia, S. ecatepecana, S. filodecaballoana, S. mascotensis, S. mexicana, S. oaxacana, S. oligophylla, S. potosina, S. rotundifolia, S. scabrelloides, andS. viejoana. In addition, two varieties,Stevia aschenborniana Sch. Bip. ex Klotzsch var.occidentalis Grashoff andS. palmeri A. Gray var.constricta Grashoff are herein redefined as being distinct species,S. occidentalis andS. constricta stat. nov.Stevia mexicana resemblesStevia trifida Lagasca but differs in the habit.