川西北高原藏原羚夏季生境选择

利用数量化理论对川西北高原藏原羚夏季生境选择进行了研究,发现影响藏原羚夏季生境选择的主要因子有水源、植被类型、隐藏条件,次要因子为食物丰盛度、人为干扰和海拔高度;其最适生境为隐蔽条件较好、水源较近的草甸草原。     

Evolutionarily stable stealing: game theory applied to kleptoparasitism

We present an individual-based model of a group of foraginganimals. Individuals can obtain food either by discovering itthemselves or by stealing it from others (kleptoparasitism).Given that challenging another individual for a discovered fooditem costs time (which could otherwise be spent searching foran undiscovered item), attempting to steal from another maynot always be efficient We show that there is generally a uniquestrategy that maximizes uptake rate—always or never challengingothers. For any combination of parameter values, we can identifywhich strategy is appropraite. As a corollary to this, we predictthat small changes in ecolgical conditions can, under some circumstances,cause a dramatic change in the aggressive behavior of individuals.Further, we investigate situations where searching for undiscoveredfood and searching for potential opportunities for stealingare mutually exclusive activities (i.e., success at one canonly be improved at the expense of the other). Using game theory,we are able to find the evolutionarily stable strategy for investmentin these two activities in terms of the ecological parametersof the model.     

基于变权-物元分析模型的老工业基地区域生态安全动态预警研究——以吉林省为例

生态安全预警是生态安全研究的重要内容,对维护区域生态安全具有重要的意义。老工业基地区域生态安全预警研究具有一定的特殊性和典型性,选取吉林省为研究区,基于压力、状态、响应(P-S-R)和生态、环境、经济、社会(E-E-E-S)框架模型构建生态安全预警指标体系,运用变权-物元分析模型对1991—2011年吉林省区域生态安全的预警等级进行了测度,并结合灰色系统GM(1,1)预测模型对2015年、2020年区域生态安全态势进行预测预警。研究结果表明:(1)1991—2011年,吉林省生态安全总体水平呈逐步上升的趋势,区域生态安全预警等级从"巨警"上升为"轻警",指示灯由"红色预警"逐步变为"蓝色预警";(2)2015年,吉林省的生态安全预警等级属于"轻警",指示灯为"蓝色预警",到2020年,吉林省的生态安全预警等级属于"无警",指示灯为"绿色预警",但具有向"轻警"变化的态势;(3)制约吉林省生态安全水平提升的主要因素包括单位面积耕地化肥负荷量、城镇化、人均水资源量、GDP增长率、第一产业占GDP比重等,这些因素应是今后生态环境保护调控的重点,本研究为吉林省经济-生态-社会可持续发展提供参考。     

菱角萤叶甲种群抽样技术研究

在研究菱角萤叶甲各虫态空间分布型的基础上,利用负二项公共Kc值;Iwao回归式中的α,β;Teylor幂法则中的a,b以及Morisita的I_δ求得理论抽样模型,从而导出在不同置信度t,不同的平均虫口密度(?)和不同允许误差D下的理论抽样数．同时利用Kuno(1969),Iwao(1975)和Willson(1983)提出的序贯抽样法,得到菱角萤叶甲各虫态的序贯抽样模型,并对这些模型进行比较．最后,结合Kuno和Iwao模型获得了菱角萤叶甲各虫态的Kuno-Iwao复合序贯抽样法,从而大大减少了在某种情况下的抽样数．     

数量遗传学中一种新的求综合性状的方法

本文运用申农(Shannon)提供的最大熵原理,提出一种构成单一综合性状的新方法,并以此与数量遗传学中的多元统计法作了比较。在作多元遗传分析吋,常用多元统计法求出多个数量性状的综合性状,再对这些相互关联的基本性状作主成份分析或用典范相关进行遗传分析。本文提出了不同于多元统计学的另一种新的方法——最大熵法求出多个数量性状的单一综合性状值。它具有数学结构简单,过程明晰,结果简明等优点。     

Manipulation of habitat isolation and area implicates deterministic factors and limited neutrality in community assembly

Theory predicts deterministic and stochastic factors will contribute to community assembly in different ways: Environmental filters should regulate those species that establish in a particular area resulting in the ecological requirements of species being the primary driver of species distributions, while chance and dispersal limitation should dictate the likelihood of species reaching certain areas with the ecology of species being largely neutral. These factors are specifically relevant for understanding how the area and isolation of different habitats or islands interact to affect community composition. Our review of the literature found few experimental studies have examined the interactive effect of habitat area and isolation on community assembly, and the results of those experiments have been mixed. We manipulated the area and isolation of rock “islands” created de novo in a grassland matrix to experimentally test how deterministic and stochastic factors shape colonizing animal communities. Over 64 weeks, the experiment revealed the primacy of deterministic factors in community assembly, with habitat islands of the same size exhibiting remarkable consistency in community composition and diversity, irrespective of isolation. Nevertheless, tangible differences still existed in abundance inequality among taxa: Large, near islands had consistently higher numbers of common taxa compared to all other island types. Dispersal limitation is often assumed to be negligible at small spatial scales, but our data shows this not to be the case. Furthermore, the dispersal limitation of a subset of species has potentially complex flow‐on effects for dictating the type of deterministic factors affecting other colonizing species.     

秦岭川金丝猴的一种自发性双足姿势的脚偏好

与手偏好相比较,脚偏好被认为是研究大脑半球中语言功能偏侧性调控表达的一种更佳的行为预测指标。当前国际科学界对于人类大脑半球功能不对称性和肢体偏好进化起源的关注,有力地推动了非人灵长类物种肢体偏好行为学研究,其中关于树栖灵长类物种的相关研究,对身体姿势在灵长类肢体偏好表达的理解有十分关键作用。川金丝猴(Rhinopithecus roxellana)是我特有濒危灵长类物种,主要营树栖生活。本研究首次关注秦岭川金丝猴自发性非移动双足姿势(双足叠放)的脚偏好。研究发现在个体水平上每个焦点动物均表现出明显的脚偏好,在群组水平上表现出显著的右脚偏好,脚偏好表达无显著性别差异,其研究结果支持“姿势起源理论”。本文首次呈现野生旧大陆猴物种群组水平脚偏好的研究证据。     

The end of the adaptive landscape metaphor?

The concepts of adaptive/fitness landscapes and adaptive peaks are a central part of much of contemporary evolutionary biology; the concepts are introduced in introductory texts, developed in more detail in graduate-level treatments, and are used extensively in papers published in the major journals in the field. The appeal of visualizing the process of evolution in terms of the movement of populations on such landscapes is very strong; as one becomes familiar with the metaphor, one often develops the feeling that it is possible to gain deep insights into evolution by thinking about the movement of populations on landscapes consisting of adaptive valleys and peaks. But, since Wright first introduced the metaphor in 1932, the metaphor has been the subject of persistent confusion, from equivocation over just what the features of the landscape are meant to represent to how we ought to expect the landscapes to look. Recent advances—conceptual, empirical, and computational—have pointed towards the inadequacy and indeed incoherence of the landscapes as usually pictured. I argue that attempts to reform the metaphor are misguided; it is time to give up the pictorial metaphor of the landscape entirely and rely instead on the results of formal modeling, however difficult such results are to understand in ‘intuitive’ terms.