Mandibular morphometric variation among Chinese cercopithecoids and the unique structure of the snub-nosed monkey (Rhinopithecus) mandible

In order to understand how mandibular structure differs among the Chinese cercopithecoids (Rhinopithecus, Trachypithecus and Macaca), particularly the uniqueness of the snub-nosed monkeys (Rhinopithecus), we analysed ten mandibular measurements by principal components analysis (PCA), and examined scaling patterns. The results provided by the PCA illustrated differences due to size among the cercopithecoids and the relationship between colobines (Trachypithecus and Rhinopithecus) and cercopithecines, in which macaques (Macaca) are included. Allometric analysis indicated that, biomechanically, there is not a marked difference between macaques and leaf-eating monkeys. This may be associated with the fact that both share some similar ecology and niches in south and southwest China. The snub-nosed monkeys exhibit a significantly more robust mandible, evident in the symphysis, corpus, condyle, and masticatory momentum arm. This supports the hypothesis, based on the study of dental structure, that Rhinopithecus is a unique group in Asian Old World monkeys (OWMs) and has developed some unique characteristics in order to adapt to the tough food available in the severe cold climate of the Plateaux of Qinghai-Tibet, Yun-Gui and Qingling in China.

Genetic variation and population structure of Indian mackerel in the southern part of BOBLME region, Indonesia

Objectives included measuring genetic variation and population structure of Indian mackerel (Rastrelliger kanagurta) in order to ascertain whether current exploitation is sustainable. .

Molecular phylogeography and population structure of a mid-elevation montane frog Leptobrachium ailaonicum in a fragmented habitat of southwest China

Leptobrachium ailaonicum is a vulnerable anuran restricted to a patchy distribution associated with small mountain streams surrounded by forested slopes at mid-elevations (approximately 2000-2600 m) in the subtropical Mount Wuliang and Mount Ailao ranges in southwest China (Yunnan Province) and northern Vietnam. Given high habitat specificity and lack of suitable habitat in lower elevations between these ranges, we hypothesized limited gene flow between populations throughout its range. We used two mitochondrial genes to construct a phylogeographic pattern within this species in order to test our hypothesis. We also examined whether this phylogeographic pattern is a response to past geological events and/or climatic oscillations. A total of 1989 base pairs were obtained from 81 individuals of nine populations yielding 51 unique haplotypes. Both Bayesian and maximum parsimony phylogenetic analyses revealed four deeply divergent and reciprocally monophyletic mtDNA lineages that approximately correspond to four geographical regions separated by deep river valleys. These results suggest a long history of allopatric separation by vicariance. The distinct geographic distributions of four major clades and the estimated divergence time suggest spatial and temporal separations that coincide with climatic and paleogeographic changes following the orogeny and uplift of Mount Ailao during the late Miocene to mid Pliocene in southwest China. At the southern distribution, the presence of two sympatric yet differentiated clades in two areas are interpreted as a result of secondary contact between previously allopatric populations during cooler Pleistocene glacial cycles. Analysis of molecular variance indicates that most of the observed genetic variation occurs among the four regions implying long-term interruption of maternal gene flow, suggesting that L ailaonicum may represent more than one distinct species and should at least be separated into four management units corresponding to these four geographic lineages for conservation. (C) 2009 Elsevier Inc. All rights reserved.

Genetic relationship of Chinese and Japanese gamecocks revealed by mtDNA sequence variation

Cockfighting has a very long history dating back to as early as 2500 years ago in China. Cockfighting was intertwined with human cultural traditions, helped disperse chickens across the world, and influenced the subsequent breed selection. Therefore, trac

A reappraisal of complete mtDNA variation in East Asian families with hearing impairment

In a number of recent studies, we summarized the obvious errors and shortcomings that can be spotted in many (if not most) mitochondrial DNA (mtDNA) data sets published in medical genetics. We have reanalyzed here the complete mtDNA genome data published

Genetic diversity and origin of Chinese cattle revealed by mtDNA D-loop sequence variation

To determine the origin and genetic diversity of Chinese cattle, we analyzed the complete mtDNA D-loop sequences of 84 cattle from 14 breeds/populations from southwest and west China, together with the available cattle sequences in GenBank. Our results sh

Genetic diversity of Chinese domestic goat based on the mitochondrial DNA sequence variation

The aim of this study was to characterize the genetic diversity of domestic goat in China. For this purpose, we determined the sequence of the mitochondrial DNA (mtDNA) control region in 72 individuals of the Yangtze River delta white goat, and reanalysed

Diversity Variation of Ground-dwelling Beetle(Insecta:Coleoptera) Communities in Jiaozi Mountain, Yunnan, China

对云南轿子雪山自然保护区地表甲虫物的种组成及生物多样性季节变化进行了连续跟踪调查.调查结果如下:(1)通过对4种典型微环境样地(草地、灌丛、林地以及农田生态系统)连续3次跟踪连续调查,共获得标本2451头,分别隶属于24科.其中步甲科(Carabidae)为优势类群,占总数的62.10%;隐翅虫科(Staphylinidae)其次,占12.77%.可能由于海拔、气温等因素影响,该地区昆虫活动高峰期较短.(2)通过对4种典型微生态环境中地表甲虫的生物多样性的比较,表明不同生境内甲虫的多样性指数存在动态变化,在不同生境片区内甲虫存在迁移活动,甲虫多在灌丛中越冬,并随季节及食物源迁移.

Geographic and economic setting of Lake Victoria

Lake Victoria, besides being the second largest in the world after Lake Superior, is the largest tropical lake. Its waters are shared by Kenya (6% of the surface area), Uganda (43%), and Tanzania (51%). Before dramatic structural and functional changes manifested in the lake's ecosystem especially in the 1980s, fish life flourished in the lake's entire water column at all times of the year. Currently, the situation is much more different from what it was in the past. The exponential increase in the introduced Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus) stocks, siltation, wetland degradation and eutrophication have characterised the lake ecosystem. The two exotic species and the small native cyprinid (Rastrineobola argentea) form the basis of the commercial fishery that was once dominated by two native tilapiines (Oreochromis esculentus and Oreochromis variabilis) and five other large-bodied endemic fishes. Severe deoxygenation observed at shallow depths (Ochumba 1990; Hecky et al., 1994) indicates that a large volume of the lake is unable to sustain fish life. The Lake Victoria catchment is one of the most densely populated areas in East Africa, encompassing a population of about 30 million people. Widespread poverty resulting from high inflation rates, lack of opportunities and general unemployment have characterised the lakeside communities over much of the last two decades. The biophysical environment in which Lake Victoria exists makes the lake particularly susceptible to changes that occur as a result of human modification to the watershed or the lake itself, thus rendering benefits from the lake unsustainable.

Facilitation of learning induced by both random and gradual visuomotor task variation.

Motor task variation has been shown to be a key ingredient in skill transfer, retention, and structural learning. However, many studies only compare training of randomly varying tasks to either blocked or null training, and it is not clear how experiencing different nonrandom temporal orderings of tasks might affect the learning process. Here we study learning in human subjects who experience the same set of visuomotor rotations, evenly spaced between -60° and +60°, either in a random order or in an order in which the rotation angle changed gradually. We compared subsequent learning of three test blocks of +30°→-30°→+30° rotations. The groups that underwent either random or gradual training showed significant (P < 0.01) facilitation of learning in the test blocks compared with a control group who had not experienced any visuomotor rotations before. We also found that movement initiation times in the random group during the test blocks were significantly (P < 0.05) lower than for the gradual or the control group. When we fit a state-space model with fast and slow learning processes to our data, we found that the differences in performance in the test block were consistent with the gradual or random task variation changing the learning and retention rates of only the fast learning process. Such adaptation of learning rates may be a key feature of ongoing meta-learning processes. Our results therefore suggest that both gradual and random task variation can induce meta-learning and that random learning has an advantage in terms of shorter initiation times, suggesting less reliance on cognitive processes.

Status and variation of invertebrates in Lakes Albert and Kyoga

Invertebrates are some of the key food items for fish diets. They thus form an important fish food environment upon which the fisheries thrives in terms of production through dietary support. Invertebrates communities of Lakes Albert and Kyoga have been evaluated and considered the implications for diets and production of commercial fishes.

Seasonal variation in ranging patterns of Yunnan snub2nosed monkeys Rhinopithecus bieti at Mt1Fuhe , China

从2000 年11 月至2002 年1 月, 我们在云南富合山(99°20′E , 26°25′N) 记录了滇金丝猴( Rhinopithe2 cus bieti) 的游走以及其他行为, 以描述猴群行为模式的季节性变化及其对温带环境的适应。由于季节间行为方 式的相似, 我们将冬季和春季、夏季和秋季的数据合并表述。猴群终年以取食树叶为主, 多在过夜地附近活动。 在冬- 春季, 猴群一般在低海拔的南部地区活动, 同时缩短日行走距离, 花费较多的时间取食树叶、竹叶和竹 笋; 而在夏- 秋季猴群的活动模式与冬- 春季相反, 并取食大量果实。我们将富合地区猴群的季节性游走模式 以及食性看作是食物供给和温度变化之间折中的结果, 这些行为特征和其它温带灵长类的相似。此外, 过夜地 的分布也会影响猴群利用家域内各方格的方式[动物学报50 (5) : 691 - 696 , 2004 ] 。

CRANIODENTAL VARIATION OF MACAQUES ( Macaca ): SIZE,FUNCTION AND PHYLOGENY

为了研究猕猴属的颅骨差异性, 从而探 讨种间在形态、功能和系统分化方面的相互联系, 测定了11 个猕猴种类的77 个颅骨变量, 用于主成 分分析和判别分析。应用巢式分析方法, 分析过程 包括3 个步骤。所有变量根据功能和部位的不同首 先分为7 个单位: 下颌、下颌齿、上颌齿、上面 颅、下面颅、面颅后部和颅腔。第2 步根据它们所 揭示的相似性(具有相同的种间及种内差异性类 型) 合并为3 个解剖区域: 咀嚼器官(下颌、下颌 齿、上颌齿) , 面颅(上面颅和下面颅) 和整个面 颅后(面颅后和颅腔) 。第3 步从3 个解剖区域筛 选出27 个变量代表整个颅骨的形态结构。除了寻 找不同的功能单位, 解剖区域及总的颅骨具有不同 的种间和种内差异类型外, 此过程对筛出研究意义 不大的变量起很重要的作用。上述分析过程分别用 于对雌、雄性和两性的研究。所研究的11 个猕猴 种类间形成了3 聚类。第1 类包括食蟹猴(Macaca f ascicularis) 、戴帽猴( M1 sinica) 和头巾猴( M1 radiata) ; 第2 类包括猕猴( M1 mulatta ) 、熊猴 (M1 assensis ) 、平顶猴( M1 nemestrina ) 和黑猿 (M1 nigra) ; 第3 类包括蛮猴( M1 sylvanus ) 、日 本猴( M1 f uscata) 、短尾猴( M1 arctoides ) 和藏 酋猴(M1 thibetana) 。分别从两性差异、食物、生态、分类和系统分化方面进行了差异性讨论, 结果 认为猕猴种间颅骨的差异性主要是由于系统分化不 同而引起个体差异所致, 即种间和种内存在的个体 差异。在主成分分析中, 这些差异在不同的区域表 现在不同的成分上。在咀嚼器官上种间的差异在第 1 主成分上, 种内的差异则在第2 主成分上。面颅 的情况则刚好相反。这两种差异在面颅后及颅腔上 则被第1 和第2 主成分所平分。这样, 种间的差异 在咀嚼器官上大于种内的差异。种内的差异在面颅 上则大于种间的差异。这两种差异在面颅后和颅腔 上则几乎大小相等。这一研究结果表明, 与传统的 概念不同, 第2 主成分不仅仅表现形态、形状的差 异, 而如同第1 主成分一样, 也表现形态的大小成 分。此研究所揭示的猕猴种间关系部分与Foden (1976 , 1980) 和Delson (1980) 相同。如平顶猴 与黑猿、短尾猴、藏酋猴和熊猴的关系。食蟹猴、 头巾猴和戴帽猴的关系则不同, 并已得到有关分子 生物学的支持, 此3 种可能来自同一祖先并经历相 同的扩散过程。此研究所设计的巢式分析过程提供 了一种很好的差异性研究手段。最终结果暗示在形 态学研究中仅仅考虑某一区域的形态结构是很不够 的, 因为不同的部分具有不同的种间及种内差异类 型。这在化石研究中尤其要注意。