The controlling factors limiting maximum body size of insects

The purpose of this study is to consider the controlling factors limiting maximum body size of insects. For this analysis, we set up and quantitatively verify the following working hypothesis: insect body sizes can be explained only by the historical changes in the oxygen supply. The present study focuses on the body size of the Protodonata and Odonata. The amount of oxygen needed and that of oxygen entering the insect body was calculated using allometric equations. The theoretical maximum sizes at each geologic time were estimated from palaeo‐atmospheric oxygen partial pressure and compared with the maximum size of known fossilized insects. The historical change in fossilized insect sizes was much larger than that in theoretical sizes. Additionally, from the Jurassic, despite an increase in the partial pressure of oxygen, which would theoretically increase maximum size, the maximum size of fossilized insects became smaller. These findings are inconsistent with the expectations of the working hypothesis. Oxygen supply is likely to partially limit the maximum size of insects with additional factors.     

人文世界里的锹甲

锹甲作为一类观赏昆虫在人文世界里受到长久的关注,文章对人文世界里的锹甲进行回顾：综述不同国家和地区中锹甲的多种称谓;从历史文化角度追溯锹甲学名的由来、锹甲与天牛科学名的关系、欧洲宗教中的锹甲、民间故事与风俗中的锹甲;从艺术欣赏角度介绍锹甲与绘画、锹甲与邮票、锹甲与装饰;着眼与现实生活,对锹甲的综合现状进行评述,并总结锹甲作为物种正面临的问题,呼吁人们在欣赏锹甲的同时,更要关注锹甲的物种多样性保护。     

How small is the smallest? New record and remeasuring of Scydosella musawasensis Hall, 1999 (Coleoptera,Ptiliidae), the smallest known free-living insect

The smallest known beetle Scydosellamusawasensis Hall is recorded for the second time. Precise measurements of its body size are given, and it is shown that the smallest examined representative of this species has a length of 325 µm.     

A Formula for the Gini Coefficient and its Decomposition

This paper is concerned with the Gini coefficient as a concentration measure of the distribution. The proposed formula for the computation of the Gini coefficient allows its decomposition according to different sub-groups of the initial population, either exactly or approximately.     

Radio-telemetric monitoring of dispersing stag beetles: implications for conservation

Migratory movements of the endangered stag beetles Lucanus cervus (18 males, 38 females) were monitored radio-telemetrically for three reproductive periods (2003–2005). The aim of the study was to estimate the migratory range of free-ranging individuals as a measure of connectivity among neighbouring populations for future conservation measures. Miniature transmitters of c . 350 mg (battery life: 10–15 days) were attached externally to the pronotum. Transmitter/beetle mass ratio was 12.8% on average (7.1–28.0%). Male dispersal behaviour consisted of frequent flights directed to sites with reproductive females and rarely of on-ground movement. Total displacement distance recorded was up to 2065 m, the maximum distance of a single flight being 1720 m. Flights always began at elevated structures such as trees and shrubs and took place in an air temperature range of 11–27°C. Within this range, temperature did not influence flight distance. Female dispersal behaviour consisted mostly of a single flight, followed by mating and consequent ground movements towards oviposition sites. Total displacement distance recorded was up to 762.6 m, the maximum distance of a single flight being 701 m. Climatic constraints of flights were the same as in males. Modelling the dispersal behaviour suggests that about 1% of males are capable of maintaining gene flux among nest sites within a radius of about 3 km. However, the colonization of new nest sites depends on the dispersal ability of females and amounts to less than 1 km. Thus, isolated populations (distance to the next population greater than 3 km) have an increased probability of local extinction.     

Is non‐loglinear allometry a statistical artifact?

The allometric equation, y = ax^b, is commonly fitted to data indirectly by transforming predictor (x) and response (y) variables to logarithms, fitting a straight line to the transformations, and then back‐transforming (exponentiating) the resulting equation to the original arithmetic scale. Sometimes, however, transformation fails to linearize the observations, thereby giving rise to what has come to be known as non‐loglinear allometry. A smooth curve for observations displayed on a log–log plot is usually interpreted to mean that the scaling exponent in the allometric equation is a continuously changing function of body size, whereas a breakpoint between two (or more) linear segments on a log–log plot is typically taken to mean that the exponent changes abruptly, coincident with some important milestone in development. I applied simple graphical and statistical procedures in re‐analyses of three well‐known examples of non‐loglinear allometry, and showed in every instance that the relationship between predictor and response can be described in the original scale by simple functions with constant values for the exponent b. In no instance does the allometric exponent change during the course of development. Transformation of data to logarithms created new distributions that actually obscured the relationships between predictor and response variables in these investigations, and led to erroneous perceptions of growth. Such confounding effects of transformation are not limited to non‐loglinear allometry but are common to all applications of the allometric method. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??.     

Leaf size and inflorescence size may be allometrically related traits

Summary Corner's rules for plant form relate the degree of branching to branch diameter, and branch diameter to leaf or inflorescence size. We report the first interspecific test of these rules for inflorescence size and branch diameter. We derived a simple corollary of Corner's rules; since leaf size and inflorescence size are both correlated to branch thickness, they may be correlated to each other. This corollary holds for Leucadendron and Protea (Proteaceae), and in certain other taxa in the Asteraceae, Bruniaceae and Pinaceae which also have leaves and reproductive structures on the same shoot. For such taxa this implies that selection for aspects of floral display (inflorescence size, pollination type) may also be expressed at the level of leaf size and vice versa. This has implications for many aspects of botany and also points to the importance of the co-ordinating role of plant architecture for aspects of plant form.     

中国水-能-粮资源适配格局动态演化及其驱动因素

在水资源供需矛盾日益趋紧的背景下,定量分析“水-能”、“水-粮”资源空间适配格局及其动态演化趋势,可为不同地区间资源优化配置以及协同管理提供参考依据。系统核算了2000—2019年中国大陆30省(自治区、直辖市)粮食与能源生产的蓝水足迹,运用基尼系数及不平衡指数等方法综合测度我国水-能-粮资源空间适配格局的演变过程,并从资源禀赋和生产结构两方面解析了资源错配的驱动因素。结果表明：(1)研究期内,反映粮-水空间适配的基尼系数保持在0.35左右,而能-水基尼系数呈现U型变化(G=0.43—0.62),总体上能源生产与水资源的空间错配程度更严重。(2)粮食、能源与水资源错配区域均呈现“北Ⅰ型、南Ⅱ型”的分布格局。研究期内,Ⅰ型错配省份均由北部、东部沿海向西部地区扩展,如黑龙江能-水关系由强-Ⅰ型错配转至轻-Ⅱ型错配。(3)水资源禀赋变化和稻谷种植规模北移共同驱动粮-水空间错配格局的演化;除黑龙江受原油减产影响较大外,火电空间布局及蓝水足迹的西移对能-水错配格局起到决定性作用。(4)粮食与水资源适配关系主要由自然属性、经济效益和农业扶持政策决定,而能-水适配主要受资源禀赋、区域经济差异和环境政...     

全球锹甲的几何形态学数据集

几何形态学是通过定量分析手段对生物的形态特征在几何空间中的变化进行测量, 并将这些测量得到的信息转变为数字信息进行统计学分析以达到形态特征间比较的目的, 目前被越来越多地用于探索生物的特征进化和多样性研究。先前的研究通常提取、比对生物的间断性特征信息用以类群之间的划分, 针对连续性特征研究的缺乏使得有关生物进化和形态学的相关知识变得匮乏。锹甲(鞘翅目: 锹甲科)由于其性二型、雄虫多型性和独特的习性成为形态学研究的重要类群。基于此, 本研究中我们提供了一个包含1,302种锹甲成虫(涵盖全世界99%已知种)的形态学数据集, 数据集包含锹甲的典型的连续性特征, 即前胸背板和鞘翅的外轮廓形态。我们提供的数据集为甲虫的生物多样性、系统发育和进化生物学在内的多个学科的研究提供基础。