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基因流是指基因从某一群体迁移至另外一个群体的所有基因迁移方式的统称。为探索长白山北部西伯利亚狍(Capreolus pygargus)局域种群间的基因流,本研究通过收集长白山北部5个西伯利亚狍局域种群279份粪便样本,使用9个微卫星位点,鉴定出215个个体,用以评估种群间遗传多样性,同时运用贝叶斯方法探讨了群体间基因流动情况。研究结果表明,5个西伯利亚狍种群遗传多样性水平(He=0.714—0.732)高于亚洲大部分西伯利亚狍种群(He=0.522—0.628)。同时5个西伯利亚狍地理种群间遗传分化程度低(FST=-0.001 1—0.018 0),群体间存在不对称基因流,且穆棱和天桥岭地区呈明显向外扩散的趋势,可初步判断为源种群。各局域种群间基因持续交流是导致种群间遗传分化低的主要原因。本研究表明长白山北部西伯利亚狍局域种群具有良好的选育和遗传潜力,是可以进行持续利用的种质资源。

采用线粒体控制区（807bp）序列分析对中国境内斑背大尾驾3个繁殖种群及1个越冬种群的遗传多样性及种群遗传结构,结果表明：斑背大尾莺的单倍型歧义度（Hd）为0.759±0.056,核苷酸多样性较（π）为0.002。三个地理种群的FST值以及繁殖种群同越冬种群之间的ΦST值表明不同地理单元之间无显著遗传分化。对不同单倍型的聚类分析（UPGMA）结果以及网络图（Network picture）结果也支持不同种群之间无显著分化。分子变异分析 （AMOVA）显示斑背大尾莺汉口亚种不同地理种群间遗传差异不大,98.5%的差异源自种群内部,仅1.5%源自种群间。中性检验结果Fu’sFS值为负值,错配分布分析结果呈单峰,表明斑背大尾驾在我国的进化史经历了种群扩张。这一假设也得到Tajima’D检验和Fu’s检验结果的支持（D=-1.80,p=0.02;Fs=-22.11,p=0.001）,该扩张大约发生在28,700年前。

利用RAPD分子标记，对引种于云南省元谋县和红河县的印楝种群进行父本分析。用12个引物对4个种群共7株树体测定了异交率，平均异交率为96．27％，异交率95％置信区间为93．50％～99．05％。对其中红河县勐龙乡大黑公种群的2株母本E和F及周围96株父本进行了基因流测定，遗传排除法确定了各有2个父本向母本E和F传粉，最大似然法分析得出有3个父本向母本E传粉，有10个父本向母本F传粉。有52．9％的传粉集中在以母本为圆心，半径30～50m的范围内。来自主风方向和逆风方向的传粉在数量上无差异。

基因流是影响植物种群的遗传组成和遗传结构的重要因子。父本分析通过直接估算基因流，对了解群体间或世代间的基因流动及性选择适合度有重要的理论意义，生产上可以指导林木种子园的设计和遗传管理。本文介绍了林木群体基因流及父本分析的研究进展，以油松种子园为例讨论了用同工酶标记进行父本分析的优缺点并论述了利用分子标记进行父本分析的优势。

Both academics and practitioners consider a lack of knowledge about evolutionary theory to be a general barrier to effectively managing genetic diversity. However, it is challenging to judge practitioners’ level of understanding and how this influences their management decisions. Knowledge built through experience may be difficult for practitioners to articulate, but could nonetheless result in appropriate management strategies. To date, researchers have assessed only the explicit (formal) knowledge practitioners have of evolutionary concepts. To explore practitioners’ understanding of evolutionary concepts, it is necessary to consider how they might apply explicit and implicit knowledge to their management decisions. Using an online survey, we asked Australian practitioners to respond to 2 common management scenarios in which there is strong evidence that managing genetic diversity can improve outcomes: managing small, isolated populations and sourcing seeds for restoration projects. In describing their approach to these scenarios, practitioners demonstrated a stronger understanding of the effective management of genetic diversity than the definitions of the relevant concepts. However, their management of genetic diversity within small populations was closer to best practice than for restoration projects. Moreover, the risks practitioners described in implementing best practice management were more likely to affect their approach to restoration than translocation projects. These findings provide evidence that strategies to build the capacity of practitioners to manage genetic diversity should focus on realistic management scenarios. Given that practitioners recognize the importance of adapting their practices and the strong evidence for the benefits of actively managing genetic diversity, there is hope that better engagement by evolutionary biologists with practitioners could facilitate significant shifts toward evolutionarily enlightened management. Tanto los académicos como los practicantes consideran que una falta de conocimiento sobre la teoría evolutiva es una barrera general para el manejo efectivo de la diversidad genética. Sin embargo, es complicado juzgar el nivel de entendimiento de los practicantes y cómo éste influye sobre sus decisiones de manejo. El conocimiento construido por medio de la experiencia puede ser difícil de articular para los practicantes, pero de igual manera podría resultar en estrategias adecuadas de manejo. A la fecha, los investigadores han evaluado solamente el conocimiento explícito (formal) que tienen los practicantes sobre los conceptos evolutivos. Para explorar el entendimiento que tienen los practicantes sobre los conceptos evolutivos es necesario considerar cómo podrían aplicar conocimientos explícitos e implícitos a sus decisiones de manejo. Por medio de una encuesta en línea, le pedimos a practicantes australianos que respondieran a dos escenarios comunes de manejo en los cuales hay fuertes evidencias de que el manejo de la diversidad genética puede mejorar los resultados: el manejo de poblaciones pequeñas y aisladas, y la obtención de semillas para proyectos de restauración. Cuando describieron susmétodos paraestosescenarios, los practicantes demostrarontener un entendimiento más completo del manejo efectivo de la diversidad genética que de las definiciones de los conceptos relevantes. Sin embargo, su manejo de la diversidad genética dentro de poblaciones pequeñas estuvo más cerca de la mejor práctica que para los proyectosderestauración. Además, los riesgosquelos practicantesdescribieronen laimplementación del manejo de la mejor práctica tuvieron una mayor probabilidad de afectar a sus estrategias de restauración que a las de reubicación. Estos resultados proporcionan evidencia de que las estrategias para construir la capacidad de los practicantes para manejar la diversidad genética deben enfocarse en escenarios realistas de manejo. Ya que los practicantes reconocen la importancia de adaptar sus prácticas y reconocen la sólida evidencia para los beneficios del manejo activo de la diversidad genética, hay esperanzas de que una mejor colaboración entre los practicantes y los biólogos evolutivos pudiera facilitar cambios significativos hacia un manejo informado evolutivamente. 研究者和保护实践者都认为，进化理论知识的缺乏常常会阻碍对遗传多样性的有效管理。然而，判断保护 实践者对进化理论的理解程度及其对他们的管理决策的影响却极具挑战。对于保护实践者来说，通过经验积累 的知识可能难以阐述，但仍然可以指导他们采取合适的管理策略。到目前为止,研究者只评估过保护实践者关 于进化概念的显性知识（形式知识）。为探究保护实践者对进化概念的理解,还应考虑他们如何将显性及隐性知 识应用于管理决策。我们通过在线调查，收集了澳大利亚保护实践者对两种常见管理情景的反应,在这两种情 景(管理小的隔离种群、追溯恢复计划中引种来源）中, 均有证据表明管理遗传多祥性可以提高保护成效。从实 践者对管理这呰情景的方法描述中可以看出，他们对遗传多祥性有效管理的理解比对相关概念定义的理解更深 刻。然而，相比于恢复项目，实践者对小种群遗传多祥性的管理方法更接近最佳实践。此外，他们描述的最佳实 践实施中的风险更有可能影响他们对恢复项目的管理方法，而不是影响迁地保护项目。这些发现证明，提升保 护实践者管理遗传多祥性能力的策略应侧重于现实中的管理场景。考虑到保护实践者已经认识到合理调整保护 实践的重要性，且积极管理遗传多祥性大有裨益，我们呼吁进化生物学家应更多地参与保护实践，以促进保护管 理在进化理论应用上的重要转向.

Male-male competition and female mate choice may both play important roles in driving and maintaining reproductive isolation between species. When previously allopatric species come into secondary contact with each other due to introductions, they provide an opportunity to evaluate the identity and strength of reproductive isolating mechanisms. If reproductive isolation is not maintained, hybridization may occur. We examined how reproductive isolating mechanisms medi- ate hybridization between endemic populations of the Red River pupfish Cyprinodon rubrofluviati- lis and the recently introduced sheepshead minnow C. variegatus. In lab-based dominance trials, males of both species won the same number of competitions. However, male C. rubrofluviatilis that won competitions were more aggressive than C, variegatus winners, and more aggression was needed to win against competitor C. variagatus than allopatric C. rubrofluviatilis. Duration of fights also differed based on the relatedness of the competitor. In dichotomous mate choice trials, there were no conspecific or heterospecific preferences expressed by females of either species. Our findings that male-male aggression differs between closely and distantly related groups, but female choice does not suggest that male-male competition may be the more likely mechanism to impede gene flow in this system.

Reinforcement--the process whereby maladaptive hybridization leads to the strengthening of prezygotic isolation between species--has a long history in the study of speciation. Because reinforcement affects traits involved in mate choice and fertility, it can have indirect effects on reproductive isolation between populations within species. Here we review examples of these ＂cascading effects of reinforcement＂ （CER） and discuss different mechanisms through which they can arise. We discuss three factors that are predicted to influence the potential occurrence of CER： rates of gene flow among populations, the strength of selection acting on the traits involved in reinforcement, and the genetic basis of those traits. We suggest that CER is likely if （1） the rate of gene flow between conspecific populations is low; （2） divergent selection acts on phenotypes involved in reinforcement between sympatric and allopatric populations; and （3） the genetic response to reinforcement differs among conspecific populations subject to parallel reinforcing selection. Future work continuing to address gene flow, selection, and the genetic basis of the traits involved in the reinforcement will help develop a better understanding of reinforcement as a process driving the production of species diversity, both directly and incidentally.

Himalayan snowcock Tetraogallus himalayensis are distributed in alpine and subalpine areas in China. We used mi- tochondrial DNA control-region data to investigate the origin and past demographic change in sixty-seven Himalayan snowcock T. himalayensis. The fragments of 1155 nucleotides from the control region of mitochondrial DNA were sequenced, and 57 poly- morphic positions defined 37 haplotypes. A high level of genetic diversity was detected in all populations sampled and may be associated isolation of the mountains and habitat fragmentation and deterioration from Quaternary glaciations. In the phylogenetic tree, all haplotypes grouped into four groups： clade A （Kunlun Mountains clade）, clade B （Northern Qinghai-Tibetan Plateau clade）, clade C （Tianshan Mountains clade） and clade D （Kalakunlun Mountains clade）. We found a low level of gene flow and significant genetic differentiation among all populations. Based on divergence time we suggest that the divergence of Himalayan snowcock occurred in the middle Pleistocene inter-glaciation, and expansion occurred in the glaciation. Analysis of mtDNA D-loop sequences confirmed demographic population expansion, as did our non-significant mismatch distribution analysis. In conclusion, limited gene flow and a pattern of partial isolation phylogeographic was found in geographic populations of T. hima- layansis based on the analysis on mtDNA D-loop sequences [Current Zoology 57 （6）： 758-767, 2011].

目的探讨反流性食管炎、Barrett食管及食管腺癌黏膜组织中Ⅰ型胶原蛋白(COL1A1)基因mRNA的表达水平及意义。方法经胃镜取材,采用荧光定量PCR方法检测反流性食管炎、Barrett食管、食管腺癌组织中COL1A1基因mRNA的表达水平。结果 COL1A1mRNA在正常组和反流性食管炎阴性组食管黏膜中呈低表达(0.154±0.119,0.152±0.105),在Barrett食管与食管腺癌食管黏膜中呈明显的高表达(0.396±0.170,0.726±0.561)。并且在从正常→反流性食管炎→Barrett食管→食管腺癌的发生、发展过程中,COL1A1mRNA的表达呈现渐进性增强,并与病期有关。结论 COL1A1基因的异常表达与反流性食管炎、Barrett食管和食管腺癌的发生、发展密切相关;COL1A1mRNA的表达水平可用作监测Barrett食管和食管腺癌早期发生及干预治疗效果的有用指标。

目的观察Robo2在小鼠肾脏发育过程中的表达情况,探讨其在肾脏发育中的作用。方法应用实时定量RT-PCR技术对胚龄12.5、13.5、14.5、15.5、16.5、17.5、18.5d和生后日龄1d、1周、5周共10组小鼠肾脏组织中的Robo2 mRNA表达水平进行半定量分析。应用免疫荧光技术检测胚龄12.5、13.5、14.5、15.5、16.5、17.5d和成年小鼠肾脏Robo2蛋白表达部位。结果实时定量RT-PCR结果显示,Robo2蛋白表达水平在胚龄12.5、13.5、14.5d时最高,随后明显下降,在出生后维持低水平表达。免疫荧光染色结果显示,Robo2最初在胚肾的后肾间充质表达,而不在输尿管芽表达,随着胚龄增加及肾脏发育,Robo2表达于后肾间充质细胞膜、围绕输尿管芽的浓缩帽状间充质、逗号形体和S形体以及肾小囊体,最终表达于肾小球足细胞。另外,部分早期肾小管上皮细胞也有微弱Robo2表达。在Robo2基因缺失后,肾单位发育异常,部分肾小管、集合管扩张。结论 Robo2通过调控后肾间充质与输尿管芽相互作用在小鼠肾脏发育过程中对肾单位发育起重要作用。