Food habits of wolvesCanis lupus in Latvia

Diet of wolvesCanis lupus Linnaeus, 1758 in Latvia was studied from 1997 to 2001 based on 302 scats and 107 stomachs. Wild ungulates (cervids and wild boarSus scrofa) and beaverCastor fiber were the dominant prey. Cervids were found in 50% of samples (62% biomass), wild boar in 25% (21% biomass), beavers in 14% (12% biomass). Wolves selected for wild boar, especially in winter when its ratio in the diet increased to 34% from 20% in summer. It was a more common prey species in the east of the country. The ratio of beavers, small rodents and plant food was higher in summer, which resulted in a broader food niche in summer than in winter (B = 2.53 versus 1.81, respectively). The role of domestic animals in the wolf diet was minimal except for winter when they were consumed as carrion (13%). More than 1/3of all stomachs investigated were empty. The average weight of stomach contents was 972.8 g. The importance of the beaver as an alternative prey is discussed. We conclude that wolves in Latvia prey mainly on wild animals and conflicts with livestock owners are only occasional and/or local.     

Genetic diversity and relatedness in different generations of the Siberian crane (Grus leucogeranus Pallas) captive population

Eight variable microsatellite loci were analyzed in terms of studying the genetic structure of different generations of a captive population of a rare endemic Russian species, the Siberian crane (Grus leucogeranus Pallas). It was shown that the founding population of natural origin (15 birds) is characterized by high genetic diversity (N _A = 6.625, H _O = 0.767, H _E = 0.731) and a lack of relatedness (R = ?0.079). In the total sample of descendents of the founders (122 individuals from generations F₁, F₁/F₂, F₁/F₃, F₂, F₂/F₃), this characteristic level of genetic variation is being maintained; however, we observed a decrease in allelic richness in some generations (F₁/F₂, F₁/F₃, F₂). We found a low level of relatedness in the sample of descendents of the founders (F₁, F₁/F₂, F₁/F₃), while the relatedness was maximal (R = 0.302) in the descendents of the breeders of the first generation. A small sample of breeders related to each other of generations F₁ and F₂ (eight birds) does not represent the entire gene pool of the founders of the Siberian Crane captive population. In view of this, we discuss the need to form a new genetically heterogeneous generation of breeders that would also include Siberian Cranes from the almost extinct Western Siberian population.     

Genetic assessment of paternity and relatedness in a managed population of cougars

Understanding the social dynamics of large carnivores is critical to effective conservation and management planning. We made the first attempt to delineate both paternity and relatedness for a population of cougar (Puma concolor) using microsatellite data. We analyzed a long-term genetic dataset collected from a hunted population in the Garnet Mountains of western Montana. We assigned paternity for 62.5% of litters sampled using both exclusion and likelihood analyses. Attempts at reconstructing unsampled paternal genotypes resulted in delineating possible sires for 8 more litters. Sires were on average younger than reported for males involved in pairings assessed via field data in other cougar populations. Although most mating pairs were unrelated, 5 of 17 pairings involved cougars with levels of relatedness corresponding to half-sibling and full-sibling or parent offspring relationship (r = 0.215–0.575). Relatedness among adult and subadult males was higher than relatedness levels among adult and subadult females. Relatedness among males in the Garnet population differed from patterns hypothesized to occur under male-biased dispersal theories for cougars. The long-term impact of the turnover of resident cougars in hunted populations is still unclear and warrants additional research. Our results highlight the utility of monitoring cougar demographic parameters using a combination of genetic and field data that in turn may assist managers with determining cougar harvest quotas or strategies, harvest seasons, sustainable harvest, and the appropriate management level of cougar populations. © 2011 The Wildlife Society.     

Genetic relatedness and group size in an aggregation economy

Summary We use Hamilton's Rule to investigate effects of genetic relatedness on the predicted size of social groups. We assume an aggregation economy; individual fitness initially increases with group size, but in sufficiently large groups each member's individual fitness declines with further increments in the size of the group. We model two processes of group formation, designated free entry and group-controlled entry. The first model assumes that solitary individuals decide to join groups or remain alone; group size equilibrates when solitaries no longer choose to join. The second model allows group members to regulate the size of the group, so that the predicted group size results from members' decisions to repel or accept intruding solitaries. Both the Nash equilibrium group size and any change in the equilibrium caused by varying the level of relatedness depend on the particular entry rule assumed. The largest equilibrium group size occurs when solitaries choose between joining or not joining and individuals are unrelated. Increasing genetic relatedness may reduce and can never increase, equilibrium group size when this entry rule applies. The smallest equilibrium group size occurs when group members choose between repelling or accepting intruders and individuals are unrelated. Under this entry rule, increasing genetic relatedness can increase and can never decrease, equilibrium group size. We extend the models' predictions to suggest when individuals should prefer kin vs non-kin as members of the same group.     

Habitat selection by wolvesCanis lupus in the uplands and mountains of southern Poland

Using data from the National Wolf Census, carried out in Poland in 2000–2001, and GIS techniques we analysed habitat selection by wolvesCanis lupus Linnaeus, 1758 in uplands and mountains of southern Poland. We compared ten habitat variables and two parameters related to wolf abundance in 52 circular plots (154 km² each) with recorded wolves and 97 randomly selected plots with no signs of wolf presence. Wolf plots were characterized by higher elevation and closer location to the state border than wolf-free plots. Furthermore, wolf plots had higher forest cover, but smaller number of villages and towns and shorter railways and roads than plots without wolves. The best model explaining wolf distribution included forest cover, number of villages, length of roads and railway lines. Compared to northern Poland, the southern part of the country offers worse habitats for wolves due to significantly denser network of settlements and transportation routes.     

Genetic diversity and population structure of teosinte

The teosintes, the closest wild relatives of maize, are important resources for the study of maize genetics and evolution and for plant breeding. We genotyped 237 individual teosinte plants for 93 microsatellites. Phylogenetic relationships among species and subspecific taxa were largely consistent with prior analyses for other types of molecular markers. Plants of all species formed monophyletic clades, although relationships among species were not fully resolved. Phylogenetic analysis indicated that the Mexican annual teosintes divide into two clusters that largely correspond to the previously defined subspecies, Z. mays ssp. parviglumis and ssp. mexicana, although there are a few samples that represent either evolutionary intermediates or hybrids between these two subspecies. The Mexican annual teosintes show genetic substructuring along geographic lines. Hybridization or introgression between some teosintes and maize occurs at a low level and appears most common with Z. mays ssp. mexicana. Phylogeographic and phylogenetic analyses of the Mexican annual teosintes indicated that ssp. parviglumis diversified in the eastern part of its distribution and spread from east to west and that ssp. mexicana diversified in the Central Plateau of Mexico and spread along multiple paths to the north and east. We defined core sets of collections of Z. mays ssp. mexicana and ssp. parviglumis that attempt to capture the maximum number of microsatellite alleles for given sample sizes.     

Genetic variation within and relatedness among wood and plains bison populations.

There are two recognized subspecies of bison, wood (Bison bison athabascae) and plains (Bison bison bison) bison. The establishment of most bison populations from a small number of individuals has raised concerns about their genetic variation. To this end, 11 bison populations were surveyed with 11 microsatellite loci in order to calculate genetic variation and genetic distances. Mean number of alleles ranged between 3.18 at Antelope Island State Park (Utah) and 6.55 at Wood Buffalo National Park (Alberta and Northwest Territories). Mean heterozygosity ranged from 0.295 at Antelope Island State Park to 0.669 at Custer State Park (South Dakota). The amount of genetic variability present in the bison populations as measured by mean number of alleles and overall probability of identity was found to correlate with the number of founders for all sampled populations. The G-test for heterogeneity revealed some evidence for the existence of subpopulations at Wood Buffalo National Park, however very small genetic distances between these subpopulations suggest that nuclear material from the plains bison introduced into Wood Buffalo National Park has diffused throughout the park. Genetic distances between the sampled populations were generally larger between than within the two bison subspecies.     

Genetic diversity within a declining natural population of Ferocactus histrix (DC) Lindsay

Ferocactus histrix is a barrel cactus that is widespread in Mexico. A population located in Llanos de Ojuelos, a semiarid zone representative of many disturbed regions in north‐central Mexico, was studied. Over a period of 10 years (1997 to 2007), the average number of individuals decreased from 21.95 to 3.53 plants per 300 m². A change in population size structure was also registered over this period of time. In 2008, a plot selected on the basis of plant abundance was established within the population and a genetic analysis was conducted with ISTR and ISSR markers. This analysis revealed low levels of genetic diversity (expected heterozygosity (H_E) = 0.073, Shannon index (I) = 0.113 and H_E = 0.178, I = 0.271, respectively) compared with those of most studied cacti species. The genetic diversity between the different life stages was also evaluated, and a gradual decrease in levels of genetic variation was observed from adults to juveniles and seedlings (H_E = 0.130, I = 0.192 to H_E = 0.103, I = 0.157). These differences, however, were not significant. Loci fixation and a decrease in the frequency of rare alleles were observed in seedling and juvenile classes. The decline in genetic variation may be associated with recent bottlenecks experienced by the population of F. histrix. If the sizes of local populations of F. histrix continue to decrease, genetic variation will be gradually lost, and the risk of extinction will increase.     

Genetic relatedness and disrupted social structure in a poached population of African elephants

We use genetic measures of relatedness and observations of female bonding to examine the demographic signature of historically heavy poaching of a population of free-ranging African elephants. We collected dung samples to obtain DNA and observed behaviour from 102 elephant families over a 25-month period in 2003–2005 in Mikumi National Park, Tanzania. Poaching reduced the population by 75% in the decade prior to the 1989 ivory trade ban; park records indicate that poaching dropped significantly in Mikumi following the ban. Using 10 microsatellite loci, DNA was genotyped in 203 elephants and pair-wise relatedness was calculated among adult females within and between groups. The Mikumi population is characterized by small group size, considerable variation in group relatedness, females with no first-order adult relatives and females that form only weak social bonds. We used gene-drop analysis and a model of a genetically intact pedigree to compare our observed Mikumi group relatedness to a simulated genetically intact unpoached expectation. The majority of groups in Mikumi contain 2 to 3 adults; of these, 45% were classified as genetically disrupted. Bonding, quantified with a pair-wise association index, was significantly correlated with relatedness; however only half of the females formed strong bonds with other females, and relatedness was substantially lower for a given bond strength as compared to an unpoached population. Female African elephants without kin demonstrated considerable behavioural plasticity in this disturbed environment, grouping with other females lacking kin, with established groups, or remaining alone, unable to form any stable adult female-bonds. We interpret these findings as the remaining effect of poaching disturbance in Mikumi, despite a drop in the level of poaching since the commercial trade in ivory was banned 15 years ago.     

Genotypic and phenotypic diversity of a baculovirus population within an individual insect host

It is becoming increasingly apparent that many pathogen populations, including those of insects, show high levels of genotypic variation. Baculoviruses are known to be highly variable, with isolates collected from the same species in different geographical locations frequently showing genetic variation and differences in their biology. More recent studies at smaller scales have also shown that virus DNA profiles from individual larvae can show polymorphisms within and between populations of the same species. Here, we investigate the genotypic and phenotypic variation of an insect baculovirus infection within a single insect host. Twenty four genotypically distinct nucleopolyhedrovirus (NPV) variants were isolated from an individual pine beauty moth, Panolis flammea, caterpillar by in vivo cloning techniques. No variant appeared to be dominant in the population. The PaflNPV variants have been mapped using three restriction endonucleases and shown to contain three hypervariable regions containing insertions of 70-750 bp. Comparison of seven of these variants in an alternative host, Mamestra brassicae, demonstrated that the variants differed significantly in both pathogenicity and speed of kill. The generation and maintenance of pathogen heterogeneity are discussed.     

滇杨种群遗传多样性与遗传结构

滇杨(Populus yunnanensis)是我国西南地区的特有树种, 具有速生、易无性繁殖、适应性强等优良特性, 是典型的南方型杨属树种。研究滇杨遗传多样性及种群结构对其种质资源的收集、保存和利用具有重要的意义。本研究从我国滇杨主要分布区云南和四川共采集了6个种群, 包括云南的昭通(ZT)、会泽(HZ)、嵩明(SM)、洱源(EY)、拉市海(LS)以及四川的美姑(MG), 共64个个体, 利用34对SSR分子标记和3对cpDNA叶绿体标记开展遗传多样性与遗传结构研究。SSR引物共检测到154个等位基因, 平均等位基因数为4.529, 观测杂合度(Ho)与期望杂合度(He)分别为0.552和0.472, 遗传分化系数(Fst)平均值为0.238, 多态性信息含量指数(PIC)平均值为0.421, 基因流(Nm)为0.806。滇杨的遗传结构分析(DAPC)与遗传距离的主坐标分析(PCoA)、UPGMA聚类分析均将6个种群划分为3个亚类: 第І亚类包括昭通种群、会泽种群和嵩明种群的4个个体, 第ІІ亚类包括嵩明种群的6个个体以及洱源种群和拉市海种群, 第III亚类为美姑种群; 嵩明种群包含第І和第ІІ两个亚类的混合遗传成分。3个cpDNA联合序列中共检测到35个变异位点, 分为13个单倍型, 其中单倍型H5在种群中分布最为广泛, 其余的单倍型均为种群特有的单倍型。分子方差分析(AMOVA)表明种群内的遗传变异大于种群间变异。研究表明滇杨不同种群的遗传分化具有地域性, 可选择就地保护; 昭通种群遗传多样性最高, 且包含7种叶绿体单倍型, 单倍型类型最多, 应优先保护。     

Genetic diversity and population structure of Moringa oleifera

Moringa is a genus of the tropical flowering plant family Moringaceae containing 13 diverse species. Among the different species, only Moringa oleifera L. is cultivated. This species has great potential in serving as a high-value crop for food, medicinal products, as well as fodder for animals, particularly in developing tropical regions of the world. In this study, the genetic diversity and population structure of world-wide collections of M. oleifera were investigated using DNA markers. A total of 19 microsatellite or simple sequence repeat (SSR) markers along with a partial sequence of the chloroplast gene atpB were used to study genetic diversity within 161 accessions of M. oleifera collected from Asia, Africa, North and South America, and the Caribbean. On average, 8.3 alleles/per SSR were amplified in each accession. A total number of 158 alleles were detected in 131 accessions collected from the wild in Pakistan and from 30 accessions obtained from ECHO (Florida). Observed heterozygosity varied from 0.16 to 0.86, with an average of 0.58, while the average PIC value was 0.59. Partial sequencing of chloroplast genes of 43 of 161 plants generated mixed patterns. These findings have demonstrated that there is a large genetic diversity present in wild collections of M. oleifera collected in Pakistan; whereas low genetic diversity is detected in cultivated accessions obtained from ECHO. Taken together, these results agree with previous reports that M. oleifera is native to the Indo-Pakistan ecological region, and provides sufficient diversity for genetic exploration as well as for genetic improvement efforts.     

Genetic diversity and population structure in contemporary house sparrow populations along an urbanization gradient

House sparrow (Passer domesticus) populations have suffered major declines in urban as well as rural areas, while remaining relatively stable in suburban ones. Yet, to date no exhaustive attempt has been made to examine how, and to what extent, spatial variation in population demography is reflected in genetic population structuring along contemporary urbanization gradients. Here we use putatively neutral microsatellite loci to study if and how genetic variation can be partitioned in a hierarchical way among different urbanization classes. Principal coordinate analyses did not support the hypothesis that urban/suburban and rural populations comprise two distinct genetic clusters. Comparison of F(ST) values at different hierarchical scales revealed drift as an important force of population differentiation. Redundancy analyses revealed that genetic structure was strongly affected by both spatial variation and level of urbanization. The results shown here can be used as baseline information for future genetic monitoring programmes and provide additional insights into contemporary house sparrow dynamics along urbanization gradients.     

Genetic diversity and population structure in urban white-tailed deer

Habitat fragmentation in urban areas has left many species isolated and vulnerable to loss of genetic variation. White-tailed deer (Odocoileus virginianus), however, thrive in urban areas. We compared genetic diversity and structure among deer in 2 urban metroparks with deer in a fenced reserve and with deer from an open, continuously distributed population to inform urban deer management. If urban deer maintain species' typical matrilineal genetic structure, removal of female groups may effectively reduce local abundance. However, if gene flow in urban areas is high, dispersal may impede efforts to reduce abundance. Although genetic diversity was high and mean relatedness was near zero in all locations, distributions of pairwise relatedness in urban metroparks and the fenced reserve contained greater proportions of closely and distantly related deer than the open locations, likely attributable to matrilineal structure. In addition, deer from the metroparks (approx. 65 km apart) were moderately differentiated (F_st = 0.092) indicating gene flow in urban areas may be less than in other landscapes. Our results indicate that removal of matrilineal groups may reduce local urban deer abundance without inducing immigration from surrounding areas. © The Wildlife Society, 2012