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  • Animal behavior can inform conservation policy, we just need to get on with the jobor can it?

    1?Conservation?Behavior?as?an??Emerging?Discipline?on?the?Brink?of??Success,?or?Unrealistic?Ideal?
    ?It?seems?intuitively?sensible?that?an?understanding?of?the?behavioral?characteristics?of?animals,?such?as?their?home?ranges,?diets,?mating?systems,?and?dispersal?me-?chanisms,?may?be?useful?to?inform?conservation?efforts?in?determining,?for?example,?suitable?reintroduction?areas,?or?the?design?of?dispersal?corridors.
    Ximena J. NELSON, Editor - 动物学报(英文版)
    文章来源: 万方数据
  • Endocrine correlates of mate choice and promiscuity in females of a socially monogamous avian mating system with alternative male reproductive phenotypes

    While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young (EPY) frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.
    Hubert SCHWABL,Willow R. LINDSAY,Douglas G. BARRON,Michael S. WEBSTER - 动物学报(英文版)
    文章来源: 万方数据
  • The evolution of copulation frequency and the mechanisms of reproduction in male Anolis lizards

    The evolution of many morphological structures is associated with the behavioral context of their use, particularly for structures involved in copulation. Yet, few studies have considered evolutionary relationships among the integrated suite of structures associated with male reproduction. In this study, we examined nine species of lizards in the genus Anolis to determine whether larger copulatory morphologies and higher potential for copulatory muscle performance evolved in association with higher copulation rates. In 10--12 adult males of each species, we measured the size of the hemipenes and related muscles, the seminiferous tubules in the testes, and the renal sex segments in the kidneys, and we assessed the fiber type composition of the muscles associated with copulation. In a series of pbylogenetically-informed analyses, we used field behavioral data to determine whether observed rates of copulation were associated with these morphologies.We found that species with larger hemipenes had larger fibers in the RPM (the retractor penis magnus, a muscle that controls hemipenis movement), and that the evolution of larg- er hemipenes and RPM fibers is associated with the evolution of higher rates of copulatory behavior. However, the sizes of the seminiferous tubules and renal sex segments, and the muscle fiber composition of the RPM, were not associated with copulation rates. Further, body size was not associated with the size of any of the reproductive structures investigated. The results of this study suggest that peripheral morphologies involved in the transfer of ejaculate may be more evolutionarily labile than internal structures involved in ejaculate production.
    Michele A. JOHNSON,Mafia Veronica LOPEZ,Tara K. WHITTLE,Bonnie K. KIRCHER,Alisa K. DILL,Divina VARGHESE,Juli WADE - 动物学报(英文版)
    文章来源: 万方数据
  • Sexual conflict and deception in poison frogs

    Kyle SUMMERS - 动物学报(英文版)
    文章来源: 万方数据
  • 硼在共存水蒸气-富硼熔体之间分配的实验研究及其地质意义

    硼作为一种常用的地球化学指示剂和示踪剂,对研究俯冲带岩石学过程、岩浆-热液分异作用、火山活动以及稀有元素、铜、金的成矿机制具有重要意义。硼具有高水溶性和挥发性,它在气体中的分配、迁移能力和存在形式有助于理解含硼矿物的形成条件、流体化学组成的演化趋势、硼同位素的分馏效应和成矿金属的富集机理。本文在200~350℃、0.19~3.43 MPa条件下实验研究了B2O3-H2O体系中硼在共存水蒸气和富硼熔体(液体)之间的分配,平衡时气相中的B2O3含量为1.06%~32.35%。200℃、250℃、300℃和350℃时硼在气体-熔体之间的表观分配系数分别为0.035、0.042、0.20和0.33,即随温度上升,硼在含水气相中的分配和迁移能力增强。含水的富 B 熔体与硼酸稀溶液体系的气体-液体分配系数变化不大,表明B2O3-H2O±NaCl 体系中硼的气-液分配能力受液体或熔体中硼含量的影响较小,而主要与温度有关。经热力学分析,350℃、0.19~1.74 MPa条件下水蒸气中的气态硼物种可能为H3BO3和HBO2,可以预计随水蒸气压力的升高, H2O的配位数将会增大, H3BO3或其他可能的气态物种H3BO3·H2O会变得更为重要。某些火山活动区可见天然硼酸结壳(升华壳)的形成,灼热和干燥的火山岩石表面有利于硼酸从气相中凝析和沉淀。本实验结果表明,某些富硼酸的火山喷气孔气体的形成可能与地下高温火山岩浆(岩体)中存在因液态不混溶作用或晚期出溶作用产生的含水富硼的残余熔体或流体有关,熔体的去气作用或流体的减压相分离导致含水气相的产生,硼则随之大量分配至含水气体中并喷出地表。
    张生,陈根文,SEWARD TM,王玉荣,胡光黔 - 地球化学
    文章来源: 万方数据
  • Age of maturation and behavioral tactics in male yellow ground squirrel Spermophilus fulvus during mating season

    Life-history theory predicts that in hibemators age of maturation is related positively to body size and negatively to the duration of active season aboveground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observations of marked individuals to determine the age of maturation in males through analysis of age-dependent variation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behavior during the mating season. Yearling males were smaller, lighter, had lower level of fecal testosterone, emerged later and had smaller home ranges than older males. Social activity and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters varied with age. Cluster analysis revealed two behavioral tactics: "active" males (adults only) emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heavier than "passive" males (both yearling and adult). Thus, males of S. fulvus reached adult size and matured after two hibernations, which is relatively fast for such a big species with short active period. Indirect evidence for copulations and high variation among yearlings in all parameters suggest that some of them might successfully compete with adults. Active tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passive tactic of residing is energy saving and good for adults in poor condition and for yearlings that are continuing to grow.
    Nina A. VASILIEVA Ekaterina V. PAVLOVA Sergey V. NAIDENKO Andrey V.TCHABOVSKY - 动物学报(英文版)
    文章来源: 万方数据
  • Evolution of deceit by worthless donations in a nuptial gift-giving spider

    Paolo Giovanni GHISLANDI,Mafia J. ALBO,Cristina TUNI,Trine BILDE - 动物学报(英文版)
    文章来源: 万方数据
  • 成都平原农田区土壤重金属元素环境基准值初步研究

    土壤重金属污染已成为制约人类社会发展及危害人类健康的重要因素,制定土壤重金属元素的环境基准值对控制土壤重金属污染及保护生态安全具有重要意义.以成都平原农田区为例,以保护地下水安全为目的,以室内模拟淋溶实验为手段,尝试性地计算了研究区不同类型土壤重金属元素的环境基准值.研究结果表明:(1)不同类型土壤各元素在土壤-水间的分配系数差异较大;(2)不同类型土壤Hg和Cd环境基准值差异不大,Hg环境基准值平均为0.3μg/g,Cd的变化范围为0.3~0.5μg/g;As和Pb环境基准值差异较大,As的变化范围为18~24 μg/g;Pb的变化范围为24~41 μg/g;(3)研究区土壤基本处于保护饮用水的安全范围之内,但黄壤中Pb、紫色土中Cd和Pb、棕壤中Hg和Pb具有潜在的影响地下水安全的生态风险.这对研究区进行风险评估具有重要的参考价值.
    王莹,侯青叶,杨忠芳,杨晓燕,金立新,李忠惠 - 现代地质
    文章来源: 万方数据
  • 《大坝与安全》期刊网站采编系统主要功能提示

    为方便大家运用,《大坝与安全》期刊网站及采编系统关于作者投稿、专家审稿、作者查询、读者下载、留言等主要功能提示如下:1.网址:http://magtech.dam.com.cn,点击网址进入网站.2.作者投稿:点击"作者投稿"板块,输入用户名和密码,进入投稿流程.请按照系统流程提示投稿.若作者尚未注册,请按照系统提示先进行注册.
     - 大坝与安全
    文章来源: 万方数据
  • 2014年中国仿真大会

    2014年10月西安中国系统仿真学会将于2014年10月在西安召开中国仿真大会,届时召开中国系统仿真学会第七届会员代表大会及《系统仿真学报》编委会全体委员大会.欢迎国内外仿真届同仁、学者、专业人士及学报的审稿人、编委、新老作者积极投稿,同时征集此次大会赞助商.本次大会由中国系统仿真学会主办,西北工业大学承办,系统仿真学报协办.一、征文内容1、建模/仿真理论、方法与技术:①仿真科学与技术的理论基础、方法学;②连续系统/离散事件系统/混合系统/智能系统的建模与仿真:③复杂系统/开放、复杂、巨系统的建模与仿真;④综合自然环境及虚拟现实环境的建模与仿真;⑤网络化建模与仿真:
     - 系统仿真学报
    文章来源: 万方数据
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