微卫星标记与灵昆鸡体重、体尺性状的相关分析

对30只灵昆鸡采用12个微卫星标记进行了遗传多样性检测,并采用最小二乘法拟合线性模型和方差分析法,分析了其与体重、体斜长、胸宽、胸深、龙骨长、骨盆宽、胫长和胫围等性状的相关性。结果表明:灵昆鸡的体重与体斜长、胸宽、胸深、龙骨长、胫长差异极显著(P<0.01);体斜长与胸宽、胸深、龙骨长、胫长差异极显著(P<0.01),与胫围差异显著(P<0.05);胸宽与龙骨长、胫长差异极显著(P<0.01),与胸深、胫围差异显著(P<0.05);胸深与龙骨长、胫长、胫围差异极显著(P<0.01);龙骨长与胫长、胫围差异极显著(P<0.01);胫长与胫围差异极显著(p<0.01);骨盆宽除了与胫围显著相关(P<0.05)外,与其余性状均无显著相关(P>0.05)。方差分析结果表明:在所测定的12个微卫星座位中,只有MCW0165座位的不同基因型对8个性状差异均不显著(P>0.05);其余座位的不同基因型对一个或多个性状差异均显著或极显著。经多重比较发现,每个性状受到多个基因座的影响。     

Body Form, Locomotion and Foraging in Aquatic Vertebrates

Four functional categories are denned to embrace the range oflocomotor diversity of aquatic vertebrates; (1) body/caudalfin (BCF) periodic propulsion where locomotor movements repeat,as occurs in cruising and sprint swimming; (2) BCF transientpropulsion where kinematics are brief and non-cylic, as occursin fast-starts and powered turns; (3) median and paired fin(MPF) propulsion, with very diverse fin kinematics, used inslow swimming and precise maneuver; (4) occasional propulsionor "non-swimming." Specialization in any one of these categoriescompromises performance in one or more of the others, therebyreducing locomotor diversity and hence behavioral options. Foodcharacteristics influencing the role of locomotion in searchand capture are; (1) distribution in space and/or time and (2)evasive capabilities. BCF periodic swimmers take food that iswidely dispersed in space/time; BCF transient swimmers consumelocally abundant evasive items and MPF swimmers consume non-evasivefood in structurally complex habitats. Locomotor specialistsunder-utilize smaller food items in exposed habitats. This resourceis exploited by smaller fish, which are locomotor generalistsbecause of predation pressures. For such locomotor generalists,locomotor adaptations for food capture are of diminished importanceand other adaptations such as suction and protrusible jaws infish are common.     

Quantitative Genetic Variation in Body Size of Mice from New Mutations

To measure the amount of new genetic variation in 6-week weight of mice arising each generation from mutation, selection lines derived from an initially inbred strain were maintained for 25 generations. An analysis using an animal model with restricted maximum likelihood was applied to estimate a mutational genetic component of variance for the infinitesimal model of many genes of small effect. Assuming that the inbred base population was at a mutation-drift equilibrium, it is estimated that the heritability for body size has increased by 1.0% per generation, with lower and upper confidence limits of 0.6% and 1.6%, respectively. A model which includes a mutational genetic component of variance fits the data much better than one involving only base population genetic variance. A model with no genetic component fits the data very poorly. An environmental covariance of body size of mother and offspring was included in the model and accounts for 10% of the variance. By using information only from the observed response to selection, the estimated increase in heritability from mutation is 0.3% per generation. These values are higher than published estimates for the increase in variance from spontaneous mutations in bristle traits of Drosophila, for which there are extensive data, but similar to estimates for various skeletal traits in mice.     

Exploring the Genetic Signature of Body Size in Yucatan Miniature Pig

Since being domesticated about 10,000–12,000 years ago, domestic pigs (Sus scrofa domesticus) have been selected for traits of economic importance, in particular large body size. However, Yucatan miniature pigs have been selected for small body size to withstand high temperature environment and for laboratory use. This renders the Yucatan miniature pig a valuable model for understanding the evolution of body size. We investigate the genetic signature for selection of body size in the Yucatan miniature pig. Phylogenetic distance of Yucatan miniature pig was compared to other large swine breeds (Yorkshire, Landrace, Duroc and wild boar). By estimating the XP-EHH statistic using re-sequencing data derived from 70 pigs, we were able to unravel the signatures of selection of body size. We found that both selections at the level of organism, and at the cellular level have occurred. Selection at the higher levels include feed intake, regulation of body weight and increase in mass while selection at the molecular level includes cell cycle and cell proliferation. Positively selected genes probed by XP-EHH may provide insight into the docile character and innate immunity as well as body size of Yucatan miniature pig.     

Scale Effects between Body Size and Limb Design in Quadrupedal Mammals

Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties – limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency – were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass^0.40); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass^1.0), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb''s potential for angular acceleration scales according to geometric similarity, whereas the hindlimb''s potential for angular acceleration scales with positive allometry.     

Genetic Variance for Body Size in a Natural Population of Drosophila Buzzatii

Previous work has shown thorax length to be under directional selection in the Drosophila buzzatii population of Carboneras. In order to predict the genetic consequences of natural selection, genetic variation for this trait was investigated in two ways. First, narrow sense heritability was estimated in the laboratory F2 generation of a sample of wild flies by means of the offspring-parent regression. A relatively high value, 0.59, was obtained. Because the phenotypic variance of wild flies was 7-9 times that of the flies raised in the laboratory, "natural" heritability may be estimated as one-seventh to one-ninth that value. Second, the contribution of the second and fourth chromosomes, which are polymorphic for paracentric inversions, to the genetic variance of thorax length was estimated in the field and in the laboratory. This was done with the assistance of a simple genetic model which shows that the variance among chromosome arrangements and the variance among karyotypes provide minimum estimates of the chromosome's contribution to the additive and genetic variances of the trait, respectively. In males raised under optimal conditions in the laboratory, the variance among second-chromosome karyotypes accounted for 11.43% of the total phenotypic variance and most of this variance was additive; by contrast, the contribution of the fourth chromosome was nonsignificant. The variance among second-chromosome karyotypes accounted for 1.56-1.78% of the total phenotypic variance in wild males and was nonsignificant in wild females. The variance among fourth chromosome karyotypes accounted for 0.14-3.48% of the total phenotypic variance in wild flies. At both chromosomes, the proportion of additive variance was higher in mating flies than in nonmating flies.     

Rate of Decrease of Genetic Variability in a Two-Dimensional Continuous Population of Finite Size

The rate of decay of genetic variability was investigated for two-dimensional continuous populations of finite size. The exact value of the rate involves a rather complicated expression (formula (4-1)). However, numerical examples indicate that in a population habitat size LxL and density D, the rate is approximately equal to (see PDF) where sigma(2) is the variance of dispersion distance assuming isotropical migration. The value given in (2) is equal to that of a panmictic population of size DL(2). It is remarkable that whether the rate assumes the value given by (1) or by (2) depends only on Dsigma(2) (a local property), which is independent of the habitat size. Since, in a one-dimensional population, this depends on both Dsigma(2) and the habitat size, there is an essential difference between the two types of population structure.-The function giving the probability of two homologous genes separated by a given distance being different alleles was also obtained, (formula (5-1)).     

禾本科植物基因组大小与种子特性的相关性分析

在检索植物C值数据库和种子数据信息库的基础上,对禾本科282种植物的基因组参数（倍性、染色体数、C值、GS值和平均每条染色体DNA含量）和种子特性（千粒重、含油量和蛋白含量）进行了统计分析。分析结果表明,禾本科植物C值在0.35～19.7 pg,大多位于1.6～3.2 pg之间,呈偏正态分布,种子千粒重在0.05～252 g,绝大多数位于0.05～20.0 g,呈偏态分布,二者平均值分别为4.14 pg和7.1 g。随着染色体倍性增加,C值在二倍体到八倍体之间显著增加,而GS值和平均每染色体DNA含量在二倍体到六倍体之间显著下降（p<0.05)。雀麦属和羊茅属随着倍性增加,C值显著增加,表现与禾本科相似的变化规律,GS值下降却不明显。相关性分析表明,禾本科植物C值与倍性、染色体数、GS值及平均每条染色体DNA含量均呈极显著正相关（p<0.01),与种子千粒重无相关性。GS值与染色体数、倍性呈极显著负相关,而与千粒重呈极显著正相关。C值与种子含油量呈显著负相关,但与种子蛋白含量之间无相关性。以上结果表明,禾本科植物在系统演化和进化过程中,主要通过倍性和染色体的增加来增大C值,可能通过某种删除或丢失机制来降低GS值,从而保持较高的适应环境能力和进化速率。     

杂色山雀体型、子代性别比与鸣唱特征的相关性研究

鸣声在鸣鸟的生活史中具有重要作用,是其与外界进行信息交流最有效的方式之一。鸟类的鸣唱与其个体因素(如体型、子代性别比等)有着十分重要的联系。为了揭示个体体型、子代性别比与鸣唱特征之间的相关性,于2014—2015年3—6月在辽宁省仙人洞国家级自然保护区对杂色山雀指名亚种Parus varius varius的鸣声进行录制,测量了各体型参数,并对每巢雏鸟进行性别鉴定。结果显示:(1)杂色山雀体型与其鸣唱的最高频率具有显著相关性,但单一体型参数(体质量、跗蹠长度)与其鸣声参数相关性均不显著;(2)鸣唱语句长度与子代性别比具有显著相关性,子代性别比与其他鸣声参数均不存在显著相关性。本研究结果有助于进一步了解小型鸟类体型与鸣唱的关系,以及鸣唱与子代性别比之间的关系。     

封闭群五指山小型猪主要脏器重量与体重的相关性分析

目的测定封闭群五指山小型猪主要脏器重量和脏器系数,对脏器重量与体重的相关性进行分析,并计算出相应的直线回归方程和多元回归方程。方法实验选用6-10月龄普通级封闭群五指山小型猪30头（其中♂16头、♀14头）,分别测定体重和7个主要脏器重量,计算脏器系数,通过SAS软件进行脏器系数的性别间比较和各脏器重与体重间的相关与回归分析。结果性别间比较,小型猪仅有心脏的脏器系数差异有显著性（P〈0.05）。除公猪的胃脏和母猪的肺脏外,所测脏器重量与体重间均有明显的正相关线性关系;多因素分析显示公猪的肝脏和肾脏,母猪的心脏、肝脏和肾脏对各自体重有影响。结论封闭群五指山小型猪主要脏器系数性别间差异较小,其体重与某些脏器重量存在一定的线性关系。     

Body Size and Termite Evolution

Termites are a monophyletic lineage within the paraphyletic Blattaria, with xylophagous cockroaches in the genus Cryptocercus as sister group. Given this ancestry, termite divergence involved a substantial leap in body plans, as they are pale, fragile, and miniaturized relative to most cockroaches. Here I suggest that the evolutionary transition to an altricial morphotype in termites is grounded in the economics of utilizing a wood diet, and occurred via a series of sequential steps associated with modifications in social behavior. The chief benefit of an altricial morphotype is suggested to be nitrogen made available by decreasing individual body size and by dispensing with a heavy, melanized cuticle. The primary costs lie in increased vulnerability to environment hazards, including predators, pathogens, and desiccation. Termites tipped the evolutionary scale via cooperative behaviors that mitigate the cost or amplify the benefit of a small, fragile morphotype, and were present in rudimentary form in their cockroach relatives. These include building behavior, cooperative feeding, allogrooming, and most notably, trophallaxis. It was the directed circulation of nitrogenous reserves via trophallactic feeding among units of the superorganism rather than their progressive storage in a large, heavily armored body that was the foundation of termite evolutionary success.     

Publication Bias in Psychology: A Diagnosis Based on the Correlation between Effect Size and Sample Size

Background

The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias.

Methods

We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values.

Results

We found a negative correlation of r = −.45 [95% CI: −.53; −.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings.

Conclusion

The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology.     

Analysis of Correlation between Body Length and Genetic Polymorphism for Loci ESTD-1 and IDHP-3 in the Atlantic Salmon Salmo salar

Correlation between body length and characteristics of genetic polymorphism for loci Me-2, IDHP-3, ESTD-1, and AAT-2 were studied in the Atlantic salmon Salmo salar. The study was based on data on genetic variation in more than 4000 fish grown at the Kandalaksha Hatchery. Of four loci studied, loci ESTD-1 and IDHP-3 were distinguished by the fact that they can be confidently considered body-length markers in the Atlantic salmon. Analysis of mean locus heterozygosity indicates a disturbance of the mechanism of negative heterosis that is characteristic of natural populations. This presumably reflects a change in the genetic diversity of the Atlantic salmon under the influence of breeding.     

Body Size and Reproductive Tactics in Varanid lizards

Body size and female reproduction in the water adult females larger than 500 mm SVL and 32 adult males Ledong, Hainan under permit to our laboratory in Hainan monitor lizard （Varanus salvator） were studied. Forty-two larger than 400 mm SVL were donated by local people in in 2013 and 2014. The largest male and female measured 745 and 755 mm SVL, respectively. The mean SVL was greater in adult females than in adult males. Males had larger heads （head width） than females of the same SVL. The smallest reproductive female in our sample was 565 mm SVL. Females produced a single clutch of 17.1 （10-23） pliable-shelled eggs per breeding season stretching from mid-June and mid-September. Clutch size and clutch mass were all positively related to female SVL. However, there was no significant linear relationship between egg mass and female SVL. Larger females generally produced more eggs, and thus heavier clutches than did smaller ones. There was no significant linear relationship between relative clutch mass and female SVL. Phylogenetic generalized least squares （PGLS） analysis, accounting for phylogenetic relationships, showed that clutch size was positively correlated with mean maternal SVL in varanid lizards. PGLS analysis showed that phylogenetic relationships did not affect clutch （or/and egg） mass and the SVL although there were significant linear relationship between clutch （or/and egg） mass and mean maternal SVL. Therefore, we could draw some general conclusions about the body size and reproductive tactics in varanid lizards that larger females generally produced more eggs, larger eggs and thus heavier clutches than did smaller ones.     

Diversity and Evolution of Body Size in Fishes

The diversity of body sizes observed among species of a clade is a combined result of microevolutionary processes (i.e. natural selection and genetic drift) that cause size changes within phylogenetic lineages, and macroevolutionary processes (i.e. speciation and extinction) that affect net rates of diversification among lineages. Here we assess trends of size diversity and evolution in fishes (non-tetrapod craniates), employing paleontological, macroecological, and phylogenetic information. Fishes are well suited to studies of size diversity and evolution, as they are highly diverse, representing more than 50% of all living vertebrate species, and many fish taxa are well represented in the fossil record from throughout the Phanerozoic. Further, the frequency distributions of sizes among fish lineages resemble those of most other animal taxa, in being right-skewed, even on a log scale. Using an approach that measures rates of size evolution (in darwins) within a formal phylogenetic framework, we interpret the shape of size distributions as a balance between the competing forces of diversification, pushing taxa away from ancestral values, and of conservation, drawing taxa closer to a central tendency. Within this context we show how non-directional mechanisms of evolution (i.e. passive diffusion processes) can produce an hitherto unperceived bias to larger size, when size is measured on the conventional log scale. These results demonstrate how the interpretation of macroecological datasets can be enriched from an historical perspective, and document the ways in which macroevolutionary and microevolutionary processes may be decoupled in the production of size diversity.