Exceptional sperm cooperation in the wood mouse

Spermatozoa from a single male will compete for fertilization of ova with spermatozoa from another male when present in the female reproductive tract at the same time. Close genetic relatedness predisposes individuals towards altruism, and as haploid germ cells of an ejaculate will have genotypic similarity of 50%, it is predicted that spermatozoa may display cooperation and altruism to gain an advantage when inter-male sperm competition is intense. We report here the probable altruistic behaviour of spermatozoa in an eutherian mammal. Spermatozoa of the common wood mouse, Apodemus sylvaticus, displayed a unique morphological transformation resulting in cooperation in distinctive aggregations or 'trains' of hundreds or thousands of cells, which significantly increased sperm progressive motility. Eventual dispersal of sperm trains was associated with most of the spermatozoa undergoing a premature acrosome reaction. Cells undergoing an acrosome reaction in aggregations remote from the egg are altruistic in that they help sperm transport to the egg but compromise their own fertilizing ability.     

Adaptive plasticity in mate preference linked to differences in reproductive effort

There is abundant evidence for the existence of marked mate preferences in natural populations, but the occurrence of within-population variation in mate preferences has received little attention and is often regarded as nonadaptive deviation from the optimal norm. Here we show experimentally that the preference of female collared flycatchers Ficedula albicollis for male forehead patch size, a sexually selected trait, varies with the time of breeding, an environmental factor with strong effects on reproductive success. Contrary to expectations based on time-constrained choice models, only late-breeding females prefer males with a large patch size. The variation in mate preference matches a seasonal change in female reproductive success: long-term data reveal a positive relationship between female reproductive success and male patch size exclusively in late breeders. In addition, female reproductive effort, as assessed by clutch size, appears to be adjusted relative to both timing of breeding and male phenotype. We conclude that not only can mate preferences display adaptive plasticity within populations, but this plasticity can also be linked to differences in reproductive investment.     

淫羊藿煎剂对雌性贡鸡免疫和生殖器官的影响

目的：研究不同剂量的淫羊藿煎制剂对雌性贡鸡免疫器官和生殖器官指数的影响.方法：对3日龄雏鸡每日灌注不同剂量的淫羊藿煎制剂,于21日龄测定免疫器官和生殖器官指数.结果：法氏囊指数和胸腺指数升高不显著（P>0.05）,脾脏和雌性生殖器官指数升高显著（P<0.05）.结论：淫羊藿作为鸡饲料添加剂可以提高雌鸡抗病能力和繁殖性能.     

Female mate-choice drives the evolution of male-biased dispersal in a social mammal

Dispersal has a significant impact on lifetime reproductive success, and is often more prevalent in one sex than the other. In group-living mammals, dispersal is normally male-biased and in theory this sexual bias could be a response by males to female mate preferences, competition for access to females or resources, or the result of males avoiding inbreeding. There is a lack of studies on social mammals that simultaneously assess these factors and measure the fitness consequences of male dispersal decisions. Here we show that male-biased dispersal in the spotted hyaena (Crocuta crocuta) most probably results from an adaptive response by males to simple female mate-choice rules that have evolved to avoid inbreeding. Microsatellite profiling revealed that females preferred sires that were born into or immigrated into the female's group after the female was born. Furthermore, young females preferred short-tenured sires and older females preferred longer-tenured sires. Males responded to these female mate preferences by initiating their reproductive careers in groups containing the highest number of young females. As a consequence, 11% of males started their reproductive career in their natal group and 89% of males dispersed. Males that started reproduction in groups containing the highest number of young females had a higher long-term reproductive success than males that did not. The female mate-choice rules ensured that females effectively avoided inbreeding without the need to discriminate directly against close kin or males born in their own group, or to favour immigrant males. The extent of male dispersal as a response to such female mate preferences depends on the demographic structure of breeding groups, rather than the genetic relatedness between females and males.     

Tug-of-war over reproduction in a social bee

One of the main transitions in evolution is the shift from solitary organisms to societies with reproductive division of labour. Understanding social evolution requires us to determine how ecological, social and genetic factors jointly influence group stability and partitioning of reproduction between group members. Here we test the role of the three key factors predicted to influence social evolution by experimentally manipulating them in a social allodapine bee. We show that increased relatedness between nestmates results in more even reproduction among group members and a greater productivity per individual. By contrast, the degree of reproductive skew is not influenced by the opportunity for solitary breeding or by the potential benefits of cooperation. Relatedness also has a positive effect on group stability and overall productivity. These findings are in line with predictions of the tug-of-war models, in which the degree of reproductive division of labour is determined primarily by selfish competition between group members. The alternative view, where the degree of reproductive skew is the outcome of a social contract between potential breeders, was not supported by the data.     

Functions of VEGF in female reproductive system

As a homodimeric glycoprotein,vascular endothelial growth factor(VEGF)is a highly specific mitogen of vascular endothelial cells.It can induce proliferation and migration,and inhibit apoptosis of endothelial cell.VEGF is involved in many processes in the female reproductive system,such as ovulation,periodical changes of endometrium,embryo implantation and development,VEGF plays important roles in some reproductive diseases,including preeclampsia and fetal hypoevolutism in uterus.Based on our studies on angiogenesis and its relevant factors in the female reproductive system these years,the functions of VEGF in female reproductive system are reviewed,and the research prospect and application of VEGF are also discussed.     

两性种群动态模型初探

研究具有相同年龄结构的两性种群动态模型，求出了两种种各的年增长率、稳定的年龄分布、净生殖率和生育值向量，结果表明，这些生命参数完全取决于两性种群中的雌性种群，从而揭示了种群动态的研究只考虑雌性种群动态的合理性。     

Rapid deposition of subcutaneous areolar tissue in response to sexual stimulation in mice

Many of the reproductive processes of house mice are regulated exteroceptively by social cues. Puberty in a female mouse, for example, is a labile event that can be accelerated markedly if the young female is housed with an adult male. The relevant male stimuli in this case are a combination of pheromonal and tactile cues. The female's responses to these cues include an immediate, sequential release of gonadotropic and ovarian hormones, which in turn evoke a series of predictable changes in most of the female's reproductive tissues and culminate in the pubertal ovulation. I report here an unexpected consequence of exposing a young female mouse to a male, namely an intense response of a non-reproductive tissue. Specifically, young female mice experience a rapid thickening of their subcutaneous areolar tissue when they are exposed to males. The proximal cause of this response seems to be largely, but not exclusively, an enhanced secretion of ovarian oestrogen.     

我国高校跨学科交叉国际合作创新平台建设的对策研究——以“中国—澳大利亚先进光电分子功能材料国际联合研究中心”创建为例

高水平跨学科交叉国际合作创新平台是我国高校吸引和稳定高层次科研人才的创新载体,其内涵建设是有志于迈向"世界一流大学"者需要思考的核心问题。眼界决定高度,胸襟决定深度和广度。科学的决策与规划、以人为本的管理艺术、完善透明的管理体制、充分信任学术带头人大胆实践等综合因素共同构成我国高水平跨学科交叉创新平台创建的基础。学术带头人放眼全球的战略性眼光、明确的平台建设目标、科学的学术定位、饱满的科研热情、不畏艰难的昂扬斗志则是高层次跨学科交叉创新平台建设成功的关键。     

Divergent sexual selection enhances reproductive isolation in sticklebacks

Sexual selection may facilitate speciation because it can cause rapid evolutionary diversification of male mating signals and female preferences. Divergence in these traits can then contribute to reproductive isolation. The sensory drive hypothesis predicts that three mechanisms underlie divergence in sexually selected traits: (1) habitat-specific transmission of male signals; (2) adaptation of female perceptual sensitivity to local ecological conditions; and (3) matching of male signals to female perceptual sensitivity. I test these mechanisms in threespine sticklebacks (Gasterosteus spp.) that live in different light environments. Here I show that female perceptual sensitivity to red light varies with the extent of redshift in the light environment, and contributes to divergent preferences. Male nuptial colour varies with environment and is tuned to female perceptual sensitivity. The extent of divergence among populations in both male signal colour and female preference for red is correlated with the extent of reproductive isolation in these recently diverged species. These results demonstrate that divergent sexual selection generated by sensory drive contributes to speciation.     

Fitness benefits of prolonged post-reproductive lifespan in women

Most animals reproduce until they die, but in humans, females can survive long after ceasing reproduction. In theory, a prolonged post-reproductive lifespan will evolve when females can gain greater fitness by increasing the success of their offspring than by continuing to breed themselves. Although reproductive success is known to decline in old age, it is unknown whether women gain fitness by prolonging lifespan post-reproduction. Using complete multi-generational demographic records, we show that women with a prolonged post-reproductive lifespan have more grandchildren, and hence greater fitness, in pre-modern populations of both Finns and Canadians. This fitness benefit arises because post-reproductive mothers enhance the lifetime reproductive success of their offspring by allowing them to breed earlier, more frequently and more successfully. Finally, the fitness benefits of prolonged lifespan diminish as the reproductive output of offspring declines. This suggests that in female humans, selection for deferred ageing should wane when one's own offspring become post-reproductive and, correspondingly, we show that rates of female mortality accelerate as their offspring terminate reproduction.     

Female choice selects for a viability-based male trait in pheasants

Recent theory on sexual selection suggests that females in species without paternal care choose mates by their secondary sexual characters because these indicate genotypic quality which will be transmitted to the offspring. These ideas are not yet empirically supported as data quantifying the relationship between female mate choice and female reproductive success are lacking. Only in one case, in Colias butterflies, has it been demonstrated unequivocally that females choose 'good genotypes' as mates and there is only one study, on Drosophila, demonstrating that mate choice increases one component of offspring fitness. Spur length of male pheasants (Phasianus colchicus) correlates with various fitness-related properties. We here present the first experimental field data showing that female pheasants select mates on the basis of male spur length and that female mate choice correlates with female reproductive success.     

扭角羚的繁殖特征及生命表初编

本文利用牙齿切片方法，共鉴定出４１号野生扭角羚四川亚种的年龄，结合野外及圈养条件下的观察资料，编制出扭角羚的生命表、内禀增长率及繁殖价表。结果表明，雌性性成熟年龄为４岁多、雄性为５岁多；雌性最大繁殖年龄为１７岁、雄性尚不完全清楚；由生命表编制出了存活曲线、死亡曲线和死亡率曲线。     

Females increase offspring heterozygosity and fitness through extra-pair matings

Females in a variety of species commonly mate with multiple males, and there is evidence that they benefit by producing offspring of higher genetic quality; however, the nature of these genetic benefits is debated. Enhanced offspring survival or quality can result from intrinsic effects of paternal genes---'good genes'--or from interactions between the maternal and paternal genomes--'compatible genes'. Evidence for the latter process is accumulating: matings between relatives lead to decreased reproductive success, and the individual level of inbreeding--measured as average heterozygosity--is a strong fitness predictor. Females should thus benefit from mating with genetically dissimilar males. In many birds, social monogamy restricts mate choice, but females may circumvent this by pursuing extra-pair copulations. Here we show that female blue tits, Parus caeruleus, increase the heterozygosity of their progeny through extra-pair matings. Females thereby produce offspring of higher reproductive value, because less inbred individuals have increased survival chances, a more elaborate male secondary sexual trait (crown colour) and higher reproductive success. The cost of inbreeding may therefore be an important factor driving the evolution of female extra-pair mating.     

Outbred embryos rescue inbred half-siblings in mixed-paternity broods of live-bearing females

Females commonly mate with more than one male, and polyandry has been shown to increase reproductive success in many species. Insemination by multiple males shifts the arena for sexual selection from the external environment to the female reproductive tract, where sperm competition or female choice of sperm could bias fertilization against sperm from genetically inferior or genetically incompatible males. Evidence that polyandry can be a strategy for avoiding incompatibility comes from studies showing that inbreeding cost is reduced in some egg-laying species by postcopulatory mechanisms that favour fertilization by sperm from unrelated males. In viviparous (live-bearing) species, inbreeding not only reduces offspring genetic quality but might also disrupt feto-maternal interactions that are crucial for normal embryonic development. Here we show that polyandry in viviparous pseudoscorpions reduces inbreeding cost not through paternity-biasing mechanisms favouring outbred offspring, but rather because outbred embryos exert a rescuing effect on inbred half-siblings in mixed-paternity broods. The benefits of polyandry may thus be more complex for live-bearing females than for females that lay eggs.     

授粉后红球姜雌性生殖器官qRT-PCR的内参基因筛选

在研究分析红球姜（Zingiber zerumet (L.) Smith）败育关键调控基因的表达中，筛选授粉后雌性生殖器官发育过程中的内参基因至关重要。本研究根据授粉后不同时间点的红球姜转录组数据库以及相关文献报道的传统内参基因，筛选出10个表达相对稳定的基因Actin-2（ACT2）、Actin-7（ACT7）、Beta tubulin-1（TUB1）、Beta tubulin-5（TUB5）、Alpha tubulin-3（TUA3）、Ubiquitin（UBQ）、Glyceraldehyde-3-phosphate dehydrogenase（GAPDH）、Elongation factor 1-alpha（EF-1）、Cyclophilin（CYP）、Histone（H2A）作为候选内参基因，采用qRT-PCR技术，结合GeNorm、NormFinder和BestKeeper软件对候选内参基因的表达稳定性进行分析。结果表明，在红球姜雌性生殖器官授粉后的发育过程中，GAPDH和UBQ的表达稳定性最好，均适合作为内参基因，且同时使用两种作为内参基因能使实时荧光定量PCR标准化分析结果更精确。因此，最终选择GAPDH和UBQ作为实时荧光定量PCR标准化分析红球姜雌性生殖器官相关基因表达的内参基因。本研究将为探究红球姜败育的分子机理奠定基础，也为近源姜属植物内参基因的筛选提供线索。     

成年树鼩（Tupaia belangeri chinensis）生殖系统的年周期变化

树和许多温带野生哺乳动物一样，属于季节性繁殖的动物。昆明地区的树其生殖季节在２至８月初，８月中至次年１月为非繁殖期。成年树的睾丸、卵巢和生殖管道的形态及重量有明显的季节性变化。雌性和雄性生殖系统的发育基本同步。     

Interpretation of the biological species concept from interspecific hybridization of two Helicoverpa species

The biological species concept defines species in terms of interbreeding. Interbreeding between spe-cies is prevented by reproductive isolation mechanisms. Based on our results of interspecific hybridi-zation between Helicoverpa armigera and Helicoverpa assulta, reproductive isolation mechanisms of the two species are analyzed. A combination of prezygotic factors (absent sex attraction and physical incompatibility of the genitalia) and postzygotic factors (female absence and partial sterility in F1 hy-brids) causes reproductive isolation of the two species. In addition, the role of interspecific hybridiza-tion in speciation is discussed.     

考虑合作费用的企业合作网络模型

基于Jackson的连接模型,将合作费用加入到企业合作网络中,并引入议价能力来表示其大小。议价能力体现了合作企业间资源的差异程度。研究分析表明,议价能力的优势可以使企业通过收取合作费用来剥夺其他企业的合作收益;拥有强议价能力的企业可以采取适当的议价策略来吸引其他企业的合作,同时,第一个和它合作的企业要付出较高的合作费用,第二个合作企业付出最低的合作费用,之后费用逐渐递增。     

A receptor that mediates the post-mating switch in Drosophila reproductive behaviour

Mating in many species induces a dramatic switch in female reproductive behaviour. In most insects, this switch is triggered by factors present in the male's seminal fluid. How these factors exert such profound effects in females is unknown. Here we identify a receptor for the Drosophila melanogaster sex peptide (SP, also known as Acp70A), the primary trigger of post-mating responses in this species. Females that lack the sex peptide receptor (SPR, also known as CG16752), either entirely or only in the nervous system, fail to respond to SP and continue to show virgin behaviours even after mating. SPR is expressed in the female's reproductive tract and central nervous system. The behavioural functions of SPR map to the subset of neurons that also express the fruitless gene, a key determinant of sex-specific reproductive behaviour. SPR is highly conserved across insects, opening up the prospect of new strategies to control the reproductive and host-seeking behaviours of agricultural pests and human disease vectors.