Quaternary palaeoenvironmental oscillations drove the evolution of the Eurasian Carassius auratus complex (Cypriniformes,Cyprinidae)

Aim We sought to reconstruct the spatio‐temporal genetic diversification in goldfish of the Carassius auratus complex, which is widely distributed in Eurasia, to test whether vicariance events or human‐mediated translocations best explained lineage divergence and genogeographical history. Location East Asia and the Oriental islands including Japan, the Ryukyus and Taiwan, and Europe, including Russia and the Czech Republic. Methods We reconstructed the matrilineal history of Eurasian goldfish using 1876 sequences from the partial mitochondrial DNA control region (426 bp) and 191 complete sequences of cytochrome b (1140 bp) from 67 localities representing most of the range of the species. Divergence times were estimated using a Bayesian Markov chain Monte Carlo approach based either on molecular clock data or on the fossil record. Genetic structure and the historical demography of populations were analysed using partial correlation tests and analyses of molecular variance. Results Three lineages had high levels of regional specificity. Lineages A and B from the main islands of Japan differed greatly from lineage C, which occurred on the mainland, Taiwan and the Ryukyus. Lineages A and B had late Pliocene origins. Six geographically constrained sublineages within lineage C had near‐simultaneous mid‐Pleistocene divergences. Main conclusions Genetic structure in the C. auratus complex appears to have been driven by palaeoenvironmental perturbations rather than human translocations. The disappearance of a land bridge in the Tsushima Strait around 3.0 Ma is responsible for the separation of Japanese and continental lineages; the estimated divergence time is 2.75–2.32 Ma. Fujian, China and Vietnam appear to have provided important refugia for the C. auratus complex during glaciation. After warm, moist summer monsoons intensified during the mid‐Pleistocene, goldfish are likely to have dispersed north‐eastwards to recolonize the Ryukyus via Taiwan and northwards to recolonize mainland China.     

Spatial Ecology of a Canada Lynx Population in Northern Maine

Abstract Canada lynx (Lynx canadensis) were listed as a federally threatened species in 14 states at the southern extent of their geographic range in March 2000, with Maine being the only state in the northeastern United States known to support a resident population. Relatively little information is known about the ecology of lynx living at the southern edge of their range, including range requirements, movements, and spatial organization. Basic knowledge of lynx ecology is needed for federal recovery planning efforts. Between 1999 and 2004, we trapped and radiocollared 43 lynx (21 M, 22 F) in northern Maine in an intensively managed and predominantly early successional forested landscape. We estimated diurnal annual and seasonal home-range size for male and female lynx using the 85% fixed-kernel home-range estimator. Annual home ranges of adult male lynx (x̄ = 53.6 km²) were more than twice the size of adult female home ranges (x̄ = 25.7 km²). Home ranges of adult females during snow periods (x̄ = 38.3 km²) were nearly 3 times larger than their snow-free-period ranges (x̄ = 14.3 km²), whereas, snow-free ranges of adult males (x̄ = 58.8 km²) were slightly larger than their snow-period ranges (x̄ = 45.2 km²). We observed a limited amount of home-range overlap among lynx of the same sex (F: x̄ = 17.2%; M: x̄ = 11.8%). Lynx of opposite sex showed more extensive overlap (x̄ = 24.3%). Most home-range shifts of resident lynx were typically not extensive. Based on territory mapping, we estimated a minimum lynx density of 9.2–13.0 lynx/100 km². We observed lynx spatial ecology and densities that were more similar to northern lynx populations when hares were abundant than to other southern lynx populations, suggesting that region-specific studies under varying habitat conditions and hare densities are needed to ensure realistic recovery goals and effective management of lynx at the southern extent of their range.     

Biogeographical study of West Siberian hemiboreal forest associations with species range overlay methods

The geographical distributions of plant communities are usually inferred from mapping relevés. Here, we study another approach to map the ranges of associations and higher syntaxa: the joint distribution of the constant species of the associations, i.e. those species most frequently found in the relevés. We ask whether the joint distribution of the species reflects the distribution of the associations and higher syntaxa. Because of limited availability of plant distribution maps we consider species occurring in more than 40% of the relevés of four associations belonging to Western and Central Siberian hemiboreal forests of the class Brachypodio pinnati–Betuletea pendulae. Those species are the most informative for syntaxonomic considerations. The joint distribution is established by overlaying the distribution maps of the species and numerically compared with the mapped distribution of the vegetation communities using Cohen's Kappa. Most species occurring in the associations have a small to mid-sized range. The range size distribution of the contributing species approaches a normal distribution after logarithmic transformation of the range sizes. The geographical extents of the associations are well reflected by the overlays of all constant species. Removing sequentially the species beginning with those having the smallest distribution ranges from the overlay leads to progressive loss of similarity between mapped and modelled range of the associations. For the higher syntaxa (order and class) the similarity between mapped and modelled range increases first but drops at the end of the removal procedure. The less widespread species are particularly important for the recognition of a local plant community, i.e. the association. In contrast, more widespread species allow the definition of the ranges of higher syntaxa and reveal more large-scale geographic relationships of the vegetation. From our quantitative assessment of mapped and modelled maps of the distribution of plant communities, we conclude that the overlay method is useful to infer the geographical extent of plant communities.     

Molecular phylogeny of Eurasian badgers (Meles) around the distribution boundaries,revealed by analyses of mitochondrial DNA and Y-chromosomal genes

Based on previous molecular and morphological analyses, Eurasian badgers are currently classified into Meles meles distributed in Europe, M. canescens in the Caucasus and Middle East, M. leucurus in continental Asia and M. anakuma in Japan. The precise locations of their distribution boundaries are still unclear. Therefore, in the present study, we clarified the phylogenetic relationships in the genus Meles around its distribution boundaries, based on mitochondrial DNA (mtDNA) and Y-chromosomal genes. From 71 badgers examined, 29 mtDNA haplotypes were identified, including new 26 types. Multiple haplotypes of SRY and CAN-SINEs were identified from 23 males, including two new haplotypes of SRY. The mtDNA phylogeny showed that the Ural Mountains were not a current distribution boundary between M. meles and M. leucurus. In addition, our results supported the hypothesis that the Bosphorus Strait is a geographical barrier between M. meles and M. canescens. The badgers from Bulgaria north of the Bosphorus Strait shared haplotypes with M. meles. On the other hand, badgers from Far Eastern Russia distributed in the eastern peripheral region of the Asian Continent had haplotypes of M. leucurus. The badgers from Norway and Finland shared haplotypes with M. meles.     

Co-Occurrence and Occupancy of Mourning Doves and Eurasian Collared-Doves

Understanding how land cover and potential competition with invasive species shape patterns of occupancy, extirpation, and colonization of native species across a landscape can help target management for declining native populations. Mourning dove (Zenaida macroura) populations have declined throughout the United States from 1965–2015. The expansion of the Eurasian collared-dove (Streptopelia decaocto), an introduced species with similar food preferences, may further threaten mourning dove populations. We analyzed data from 2009–2016 from a large-scale monitoring program in the Western Great Plains of the United States in a 2-species occupancy model to assess the effects of collared-doves on mourning dove distributions, while accounting for imperfect detection and variation in land cover across the landscape. Mourning dove occupancy was stable or increasing across our study area, and despite overlap in resource use and co-occurrence between mourning doves and Eurasian collared-doves, we found no evidence that collared-doves are extirpating mourning doves from preferred habitat during the breeding season. © 2020 The Wildlife Society.     

Ecology and adaptation of stunted growth in fish

Dwarf individuals are observed in many species of freshwater fish. This paper studies the potential causes of such stunted growth. We present a model which describes the effect of growth conditions on the age- and size-structure of fish populations. The model parameters are chosen to characterize a Eurasian perch population. Two possible causes of stunting are identified: resource limitation and size- or age-dependent survival probabilities. While the former mechanism often arises from intraspecific density dependence, the latter is of particular relevance in the context of interspecific interactions and fishing. After evaluating the immediate ecological consequences of these factors, we examine the potential for life-history adaptations in stunted fish populations. Interactions between the ecological and adaptive mechanisms of stunting are shown to be intricate: not only does the age at maturity of individuals affect their growth trajectories, but, in addition, alterations in growth conditions can result in different adaptively stable ages at maturity. We show that such adaptive responses can either alleviate or amplify stunting caused by ecological factors. Life-history adaptation may also lead to the persistence of stunting when ecological factors alone would allow for normal growth. An appreciation of the interplay between ecological and adaptive factors therefore is critical for understanding the causes and mechanisms of stunted growth. This revised version was published online in July 2006 with corrections to the Cover Date.     

Management measures to control a feline leukemia virus outbreak in the endangered Iberian lynx

The feline leukemia virus (FeLV) is a retrovirus that affects domestic cats all over the world. Its pathogenic effects generally include anemia, immunosuppression or tumors. Dissemination over populations is linked to cat sociality, because the virus is transmitted by direct contact. Although the domestic cat is its common host, FeLV infection has also been described in some wild felids. In the Iberian lynx Lynx pardinus , some sporadic FeLV infection cases have been reported since 1994, but an outbreak with the involvement of several animals has never been described until now. During spring 2007, an FeLV outbreak hit the Doñana (SW Spain) population. The infection rapidly spread throughout the densest subpopulation throughout Doñana. Infected animals showed very acute anemic disease, most of them dying in <6 months. To avoid FeLV dissemination, a control program was carried out that included removal of viremic lynxes, vaccination of negative individuals and reduction of the feral cat population. The program was implemented both in Doñana and in Sierra Morena populations. In Doñana, around 80% of the total lynx population and 90% of the outbreak focus subpopulation were evaluated. Seven out of the 12 infected individuals found died and two reverted to latency; the remaining viremic animals have been kept in captivity. The outbreak appears to have been successfully confined to the subpopulation where the virus appeared and no more cases have been found since August 2007. In the larger Sierra Morena population, 8% of the lynx population was surveyed. Thirty-four uninfected Iberian lynxes were vaccinated at least once. The FeLV prevalence was found to be 27% in the Doñana population and 0% in the Sierra Morena population.     

北京4种鸟类分布新纪录

报道了斑鱼狗(Ceryle rudis)、白斑军舰鸟(Fregata ariel ariel)、棕背伯劳(Lanius schach schach)、乌鸫(Turdus merula)4个北京鸟类的新分布记录.以上鸟类未记载于<北京鸟类志>、<北京脊椎动物检索表>和相关文献中,为近年来北京地区新发现的鸟类,在<中国鸟类...     

Genetic diversity and phylogeography of broomcorn millet (Panicum miliaceum L.) across Eurasia

Broomcorn millet (Panicum miliaceum L.) is one of the world's oldest cultivated cereals, with several lines of recent evidence indicating that it was grown in northern China from at least 10,000 cal bp. Additionally, a cluster of archaeobotanical records of P. miliaceum dated to at least 7000 cal bp exists in eastern Europe. These two centres of early records could either represent independent domestications or cross-continental movement of this cereal that would predate that of any other crop by some 2 millennia. Here, we analysed genetic diversity among 98 landrace accessions from across Eurasia using 16 microsatellite loci, to explore phylogeographic structure in the Old World range of this historically important crop. The major genetic split in the data divided the accessions into an eastern and a western grouping with an approximate boundary in northwestern China. A substantial number of accessions belonging to the 'western' genetic group were also found in northeastern China. Further resolution subdivided the western and eastern genepools into 2 and 4 clusters respectively, each showing clear geographic patterning. The genetic data are consistent with both the single and multiple domestication centre hypotheses and add specific detail to what these hypotheses would entail regarding the spread of broomcorn millet. Discrepancies exist between the predictions from the genetic data and the current archaeobotanical record, highlighting priorities for investigation into early farming in Central Asia.