Kin associations and direct vs indirect fitness benefits in colonial cooperatively breeding sociable weavers Philetairus socius

Indirect fitness benefits are believed to be an important force behind the evolution of cooperative breeding. However, helpers may associate with their relatives as a result of delayed dispersal, hence, kin associations might be a consequence of demographic viscosity rather than active choice. In addition, recent studies showed that helpers may have access to reproduction therefore direct benefits might also play an important role. Here, we investigate the possible roles of direct genetic benefits and kin associations on helping behavior in the sociable weaver Philetairus socius, a colonial and cooperatively breeding passerine. We used a microsatellite-based genotyping method to describe the genetic structure within nests and colonies. Within a colony, we found considerable genetic structure between males but not females. Sociable weaver colonies have several nests that are simultaneously active, giving individuals a choice of associating with a range of first-order kin to unrelated individuals. Helpers were significantly more related to the young in the helped nests than in other nests of the colony, suggesting an active choice for associating with kin. The helpers were generally offspring or first-order relatives of one (50%) or both (43%) breeders, although more infrequently, seemingly unrelated individuals also helped (7%). We found no supporting evidence of extrapair parentage and hence no direct genetic gains from helping in our population. This strong reproductive skew is contrary to theoretical models predicting conflicts over reproduction in stepfamilies. We discuss whether female decisions and/or other direct benefits of remaining in kin associations or helping might explain the high skew observed.     

Kin-related spatial structure in brown bears Ursus arctos

Kin-related social structure may influence reproductive success and survival and, hence, the dynamics of populations. It has been documented in many gregarious animal populations, but few solitary species. Using molecular methods and field data we tested: (1) whether kin-related spatial structure exists in the brown bear (Ursus arctos), which is a solitary carnivore, (2) whether home ranges of adult female kin overlap more than those of nonkin, and (3) whether multigenerational matrilinear assemblages, i.e., aggregated related females, are formed. Pairwise genetic relatedness between adult (5 years and older) female dyads declined significantly with geographic distance, whereas this was not the case for male–male dyads or opposite sex dyads. The amount of overlap of multiannual home ranges was positively associated with relatedness among adult females. This structure within matrilines is probably due to kin recognition. Plotting of multiannual home-range centers of adult females revealed formation of two types of matrilines, matrilinear assemblages exclusively using an area and dispersed matrilines spread over larger geographic areas. The variation in matrilinear structure might be due to differences in competitive abilities among females and habitat limitations. The influence of kin-related spatial structure on inclusive fitness needs to be clarified in solitary mammals.     

Extra-pair paternity and male characteristics in the pied flycatcher

The pied flycatcher (Ficedula hypoleuca) is sexually dichromatic with extreme variation in male plumage coloration. The benefit for males of having black plumage is controversial, and few studies have found evidence for a sexual selection benefit of being black rather than brown. However, blacker males may be better able to achieve extra-pair fertilizations (EPFs), which may be an important component of sexual selection. We studied the role of EPFs in sexual selection in the pied flycatcher by establishing a set-up where two males with different back coloration (blacker vs browner) bred simultaneously near each other. DNA fingerprinting analysis revealed that 11% of offspring resulted from EPFs, and that 22% of broods included extra-pair young (EPY) among 36 nests containing 223 nestlings. We found no evidence that browner males suffered more often from EPFs than blacker males. There was no correlation of male or female morphology or age with EPF frequency. However, breeding pairs with low genetic similarity had EPY in their nests significantly more often. Thus we argue that females paired with genetically dissimilar males may try to avoid the effects of extreme outbreeding by seeking extra-pair copulations (EPCs). Alternatively, incompatibility between genetically dissimilar mates may simply expose females to more extra-pair copulations.     

Paternal age and offspring growth: separating the intrinsic quality of young from rearing effects

Younger individuals are often less successful in reproduction than older ones. This might be because of improving breeding skills with age or because the genetic quality of young or early maternal effects on them vary with parental age. However, no attempt has been made to experimentally separate these processes in vertebrates. We conducted a cross-fostering experiment in collared flycatchers (Ficedula albicollis) in three breeding seasons to disentangle origin- and rearing-related effects of paternal age on chick growth, while controlling for date-specific environmental conditions as well as differences in clutch and brood size. The age of the male at the nest of origin, but not that of the rearing male, had a year-dependent effect on nestling body mass and tarsus length. In two seasons, young of subadult males grew slower in the early linear phase of growth than young of adult males. There was no compensatory growth in the final asymptotic phase, so both body mass and tarsus length before fledging reflected the differential early development. In the remaining year, the age of the male at the nest of origin had no significant effect on chick growth. The environment-dependent origin effect we detected was unexplained by incubation times, hatching asynchrony, chick masses at swapping or previously described age-dependent egg quality patterns. Our results therefore suggest a genotype × environment interaction on the relative development of offspring sired by subadult and adult males. Our results also raise the possibility that female birds may gain genetic benefits by mating with older males. Further studies should identify general patterns of male age-dependent female mate choice and offspring quality in different environmental conditions.     

事故危险废物的处理、处置程序

介绍了深圳市清水河危险品仓库爆炸事故废物的处置过程，提出了对于偶发性危险废物进行处置技术标准的制定原则与废物填埋处置所应遵循的管理程序。     

沈阳市环保产业发展规划简介

主要介绍《沈阳市环保产业“十五”计划及 2 0 1 0年发展规划》的编制过程、结构框架 ,以及内容要点。     

基于CDIO的安全工程课程教学改革研究——以《工业通风》为例

为培养符合新工科人才能力要求、工程教育专业认证人才培养要求的安全工程人才,根据CDIO理念以及工业通风课程特征,论文提出以通风系统设计过程为导向的工业通风模块式教学模式,形成了6个基本能力训练项目和1个综合能力训练项目为核心的能力培养体系,提出了能力达成的教学方法以及着重能力培养过程评价的课程考核方法。     

二氧化硫专项清洁生产审核研究

按国家关于清洁生产审核的具体环保要求,针对二氧化硫产出量与总量控制的相关标准,提出关于二氧化硫专项清洁生产审核研究的具体思路.根据对哈尔滨某集团有限公司SO2专项清洁生产审核,通过组织筹划、预评估,确定二氧化硫作为清洁生产审核的重点并制定清洁生产目标,评估过程中要依据具体的国家环保要求,对于确定的方案进行环境-经济-社会效益的分析.共提出10个清洁生产方案,其中无/低费方案8个,中/高费方案2个.     

Morphometric variables of honeybees Apis mellifera used in ecotypes characterization in Argentina

The honeybee Apis mellifera has evolved in different environments and has developed different ecotypes. The objective of the Honeybee Genetic program in Argentina (MeGA) is to select honeybees adapted to different regions in the country using an important number of colonies as base population. In the last years, morphometric analyses are being incorporated into the Program as a tool for characterization of genetic materials; this fact has motivated the present work. A random sample of honeybee workers (250) was taken from 30 colonies situated in different regions in the country. The proboscis, right hind leg, right forewing and hind wing were placed on a slide and the following variables were measured: length and width of forewing and hind wing, different angles and length of wing veins, the length of the tibia, femur and metatarsi, the width of the metatarsi and the length of the proboscis. Thirty morphometrical variables were analyzed and the distribution and relation between them were recorded.     

A chemical residue survey in relation to the 1930 spruce budworm spray program in New Brunswick (Canada)

Abstract

This paper describes the results from a pesticide residue survey conducted in relation to the 1980 spraying of insecticides in New Brunswick (Canada) to preserve the coniferous forest from an on‐going spruce buciworm infestation. A total of 465 water and air samples were collected from 12 sites throughout the Province.

In water, fenitrothion was usually detected at about the same time that spraying occurred in the immediate area of the sites. The maximum that was ever detected was 2 0.0 ppb and persistence was usually United to a few days except in a small pond where fenitrothion was detected for a total of 18 consecutive days. Aminofenitrothion was also detected at a maximum of 8.0 ppb.

Fenitrothion was only detected occasionally in air samples the maximum being 1.2 ng/dm³. However, aminofenitrothion was present in several air samples at c. maximum of 12.0 ng/dm ³.