Dietary and Physical Activity Correlates of Long-Term Weight Loss

Covariations in body mass index (BMI), physical activity, macronutrient intake, and the frequency of consumption of specific foods were examined among 82 men and 75 women participating in a behavioral weight loss program over a period of 18 months. Results of repeated measures analyses of covariance showed that BMI change was inversely related to change in physical activity and change in frequency of vegetable consumption. BMI change was positively related to change in calorie intake from fat and change in frequency of consumption of beef, hot dogs, and sweets. Change in fat calories predicted BMI change better than change in total calories. In addition, change in the frequency of consumption of specific foods accounted for a larger percentage of the variance in BMI change than did change in macronutrients (10.4% vs. 5.2%). No differences were found between predictors of weight loss vs. weight maintenance.     

Communicating the consensus on climate change to college biology majors: The importance of preaching to the choir

College and university biology majors who are not climate change deniers may yet be unaware of the degree of scientific consensus on climate change and unprepared to communicate about climate science to others. This study reports on a population of climate change accepting biology majors at a large, private research university in the American northeast. Our students tended to greatly underestimate the degree of scientific consensus around climate change, to be only moderately worried about climate change, and to be unconfident in their ability to communicate about the state of the scientific consensus around climate change. After an introduction to the scholarly literature that substantiates and quantifies the scientific consensus on climate change in the context of a course on biological research literature, our students showed significant increases in their estimates of the consensus on climate change, and their estimates were more accurate. Additionally, they became more worried about climate change as well as more confident in their ability to communicate about the scientific consensus to others. These results are in line with the Gateway Belief Model, which positions perception of scientific agreement on climate change as an important driver of acceptance and motivation toward action.     

Toward a conceptual synthesis for climate change responses

Aim To identify hypotheses for how climate change affects long‐term population persistence that can be used as a framework for future syntheses of ecological responses to climate change. Location Global. Methods We surveyed ecological and evolutionary concepts related to how a changing climate might alter population persistence. We organized established concepts into a two‐stage framework that relates abiotic change to population persistence via changes in the rates or outcomes of ecological and evolutionary processes. We surveyed reviews of climate change responses, and evaluated patterns in light of our conceptual framework. Results We classified hypotheses for population responses to climate change as one of two types: (1) hypotheses that relate rates of ecological and evolutionary processes (plasticity, dispersal, population growth and evolution) to abiotic change, and (2) hypotheses that relate changes in these processes to four fundamental population‐level responses (colonization, acclimatization, adaptation or extinction). We found that a disproportionate emphasis on response in the climate change literature is difficult to reconcile with ecological and evolutionary theories that emphasize processes. We discuss a set of 24 hypotheses that represent gaps in the literature that limit our ability determine whether observed climate change responses are sufficient to facilitate persistence through future climate change. Main conclusions Though theory relates environmental change to fundamental ecological and evolutionary processes and population‐level responses, clear hypotheses based on theory have not been systematically formulated and tested in the context of climate change. Stronger links between basic theory and observed impacts of climate change are required to assess which responses are common, likely or able to facilitate population persistence despite ongoing environmental change. We anticipate that a hypothesis‐testing framework will reveal that indirect effects of climate change responses are more pervasive than previously thought and related to a few general processes, even though the patterns they create are incredibly diverse.     

气候变化与生物多样性之间的复杂关系和反馈机制

气候变化与生物多样性丧失是人类社会正在经历的两大变化。气候变化影响生物多样性的方方面面, 是导致生物多样性丧失的一个主要驱动因子; 反过来, 生物多样性丧失会加剧气候变化。因此, 阻止甚至扭转气候变化和生物多样性丧失是当前人类社会亟需解决的全球性问题,但我们对气候变化与生物多样性之间的复杂关系和反馈机制尚缺乏清晰认识。本文总结了近年气候变化与生物多样性变化的研究进展, 重点概述了不同组织层次、空间尺度和维度的生物多样性对气候变化的响应和反馈等相关领域的研究进展和存在的主要问题。结果发现多数研究关注气候变化对生物多样性的直接影响, 涉及到生物多样性的不同组织层次、维度和营养级, 但针对气候变化间接影响的研究仍然较少, 机理研究同样需要加强; 生物多样性对生态系统功能影响的环境依赖和尺度推演、生物多样性对生态系统多功能性的作用机理和量化方法是当前研究面临的挑战; 生物多样性对生态系统响应气候变化的作用机制尚无统一的认识; 生物多样性对气候变化的正、负反馈效应是国内外研究的盲点。最后, 本文展望了未来发展方向和需要解决的关键科学问题, 包括多因子气候变化对生物多样性的影响; 减缓和适应气候变化的措施如何惠益于生物多样性保护; 生物多样性与生态系统功能的理论如何应用到现实世界; 生物多样性保护对实现碳中和目标的贡献。     

Geographic disparities and moral hazards in the predicted impacts of climate change on human populations

Aim It has been qualitatively understood for a long time that climate change will have widely varying effects on human well‐being in different regions of the world. The spatial complexities underlying our relationship to climate and the geographical disparities in human demographic change have, however, precluded the development of global indices of the predicted regional impacts of climate change on humans. Humans will be most negatively affected by climate change in regions where populations are strongly dependent on climate and favourable climatic conditions decline. Here we use the relationship between the distribution of human population density and climate as a basis to develop the first global index of predicted impacts of climate change on human populations. Location Global. Methods We use spatially explicit models of the present relationship between human population density and climate along with forecasted climate change to predict climate vulnerabilities over the coming decades. We then globally represent regional disparities in human population dynamics estimated with our ecological niche model and with a demographic forecast and contrast these disparities with CO₂ emissions data to quantitatively evaluate the notion of moral hazard in climate change policies. Results Strongly negative impacts of climate change are predicted in Central America, central South America, the Arabian Peninsula, Southeast Asia and much of Africa. Importantly, the regions of greatest vulnerability are generally distant from the high‐latitude regions where the magnitude of climate change will be greatest. Furthermore, populations contributing the most to greenhouse gas emissions on a per capita basis are unlikely to experience the worst impacts of climate change, satisfying the conditions for a moral hazard in climate change policies. Main conclusions Regionalized analysis of relationships between distribution of human population density and climate provides a novel framework for developing global indices of human vulnerability to climate change. The predicted consequences of climate change on human populations are correlated with the factors causing climate change at the regional level, providing quantitative support for many qualitative statements found in international climate change assessments.     

How long before a change in soil organic carbon can be detected?

When planning sampling in an experiment where soil organic carbon (SOC) content is expected to change, it is necessary to know how many samples will need to be taken to demonstrate a change in SOC and after how long this change will be detectable. Much has been published on the number of samples required to demonstrate the minimum detectable difference in SOC, but less on how long it takes for this change to be detectable. In this paper, a model of SOC dynamics is used to estimate the minimum time taken for a change in total SOC content to become measurable under different carbon inputs, land uses and soil types. For free air carbon dioxide enrichment (FACE), and other experiments in which SOC is expected to increase, relationships between the percentage change in C inputs and the time taken to measure a change in SOC are presented, for two levels of sampling intensity corresponding to the maximum that is practically possible in most experiments (～100 samples) and that used regularly in field experiments (10–20 samples). In FACE experiments, where C inputs increase by a maximum of about 20–25%, SOC change could be detected with 90% confidence after about 6–10 years if a sampling regime allowing 3% change in background SOC level (probably requiring a very large number of samples) were used, but could not be detected at all if a sampling regime were used that allowed only a 15% change in background SOC to be detected. If increases in C inputs are much below 15%, it might not be possible to detect a change in soil C without an enormous number of samples. Relationships between the change in C inputs and the time taken to measure a change in SOC are robust over a range of soil types and land uses. The results demonstrate how models of SOC dynamics can be used to complement statistical power analyses for planning when, and how intensively, to sample soils during experiments. An advantage of the modelling approach demonstrated here is that estimates of the minimum time taken for a change in soil carbon to become detectable can be made, even before any detailed soil samples are taken, simply from estimates of the likely increase in carbon inputs to the soil (via expected changes in net primary production).     

Preaching to the choir or composing new verses? Toward a writerly climate literacy in introductory undergraduate biology

Climate change is one of the most pressing issues facing society today, yet a wide range of misconceptions exist in society about whether or why climate change is happening, what its consequences are, and what can be done to address it. Large introductory biology courses present an opportunity to teach a large number of students—some of whom may never take another course focused on climate, ecology, or the environment—about climate change. However, content knowledge alone may not be enough to prepare students to transform their knowledge into action. To begin understanding how content knowledge interacts with student constructions of climate change solutions, we administered and quantitatively analyzed a survey that examined student views of climate change and how they shifted with instruction during an undergraduate introductory biology course at a large Midwestern university. Almost all participants entered the course agreeing that climate change is occurring, and their certainty about the science of climate change increased after instruction. After taking the course, more participants described climate change as having more immediate impacts, reporting that climate change is already harming people and that climate change will harm them personally. However, both at the beginning and end of the course, participants tended to think that humans would either be unable or unwilling to reduce climate change. They were also more worried about climate change at the end of the course than they were before. Increased concern might result from students becoming more certain of the science and severity of climate change, while remaining pessimistic that humans will effectively act on climate change. This pattern suggests instructors have opportunities to modify curricula in ways that leave students with a greater sense of empowerment and efficacy; we suggest questions that instructors can ask themselves in order to modify their courses with this goal in mind.     

Tracking a changing environment: optimal sampling, adaptive memory and overnight effects

Foraging in a variable environment presents a classic problem of decision making with incomplete information. Animals must track the changing environment, remember the best options and make choices accordingly. While several experimental studies have explored the idea that sampling behavior reflects the amount of environmental change, we take the next logical step in asking how change influences memory. We explore the hypothesis that memory length should be tied to the ecological relevance and the value of the information learned, and that environmental change is a key determinant of the value of memory. We use a dynamic programming model to confirm our predictions and then test memory length in a factorial experiment. In our experimental situation we manipulate rates of change in a simple foraging task for blue jays over a 36 h period. After jays experienced an experimentally determined change regime, we tested them at a range of retention intervals, from 1 to 72 h. Manipulated rates of change influenced learning and sampling rates: subjects sampled more and learned more quickly in the high change condition. Tests of retention revealed significant interactions between retention interval and the experienced rate of change. We observed a striking and surprising difference between the high and low change treatments at the 24 h retention interval. In agreement with earlier work we find that a circadian retention interval is special, but we find that the extent of this ‘specialness’ depends on the subject's prior experience of environmental change. Specifically, experienced rates of change seem to influence how subjects balance recent information against past experience in a way that interacts with the passage of time.     

土地覆盖变化检测方法比较——以内蒙古草原区为例

随着对地观测技术的不断发展,遥感影像分辨率逐渐提高,促进了基于遥感影像的变化检测从传统像元级的检测向面向对象的检测转变。为了探究面向对象的变化检测方法在土地覆盖变化检测中的有效性和适用性,对面向对象的变化检测方法与常规的变化检测方法进行对比评价。以内蒙古鄂尔多斯和包头地区为试验区,选取2002年及2011年的Landsat TM/ETM+影像为数据源,比较了图像代数运算、图像变换、图像空间结构特征和面向对象的多种变化检测方法,对研究区两期土地覆盖进行了变化检测研究。结果表明:面向对象的变化检测方法在总体精度、kappa系数上都有明显的优越性,总体精度均在87.42%以上,尤其以面向对象的变化矢量分析方法精度最高,达91.56%。此外,主成分差异法也有较好的检测效果,总体精度为87.83%。对总体精度较高的3种方法在不同土地覆盖变化类型中检测效果的研究表明:对于研究区几种主要土地覆盖变化类型,面向对象的变化矢量分析法均有较理想的检测效果,平均精度为85%左右,且始终优于面向对象的光谱向量相似法,以居民地及旱地相关的变化类型最为明显;主成分差异法对不同土地覆盖变化类型检测效果差异很大,对其中4种变化类型的精度甚至达到了93%以上,但对于检测草地与裸地间转化精度很低,甚至只有8.69%;在与工矿用地有关的土地覆盖变化类型中,面向对象的变化矢量分析法的精度明显高于主成分差异法,而在与居民地有关的变化类型中,主成分差异法表现出一定优势。     

Artificial selection for responsiveness to photoperiodic change alters the response to stationary photoperiods in maternal induction of egg diapause in the rice leaf bug Trigonotylus caelestialium

Female adults of the rice leaf bug Trigonotylus caelestialium (Kirkaldy) (Heteroptera: Miridae) produce non-diapause eggs under long-day conditions, whereas they produce diapause eggs under short-day conditions. These egg-production modes change following a photoperiodic change from long-day to short-day conditions or vice versa, with individual variations in responsiveness shown in the time from the photoperiodic change to the mode change. Strains of this insect with higher or lower responsiveness to photoperiodic change were established after several generations of selection, indicating that the individual variation has a genetic basis. The selected strains that were more responsive and less responsive to one photoperiodic change were found to be less responsive and more responsive to the opposite photoperiodic change, respectively, indicating a significant negative correlation between responsiveness to reciprocal photoperiodic changes. The selected strains also had a significantly different incidence of diapause-egg producers in stationary photoperiods compared to a non-selected strain, showing that selections for responsiveness to photoperiodic change were essentially the same as selections for a higher or lower incidence of diapause-egg producers. These results indicate that responsiveness to photoperiodic change is one aspect of the tendency to produce diapause or non-diapause eggs.     

生物多样性保护适应气候变化的管理策略

应对气候变化和保护生物多样性是2大全球性热点环境问题。气候变化导致物种多样性丧失、生态系统服务降低和区域生态安全屏障功能受损,威胁到中国国土生态安全格局和生态脆弱区域的可持续发展,给生物多样性保护带来新的挑战。做好生物多样性保护适应气候变化的风险管理工作,既是生物多样性应对气候变化风险的必要措施,也是减缓气候变化的重要途径。结合爱知目标10的实现情况,分析了欧盟、澳大利亚、美国等发达国家发布的生物多样性适应气候变化技术政策制定情况、中国生物多样性应对气候变化进展情况,剖析了中国生物多样性保护适应气候变化存在的问题,包括生物多样性应对气候变化的科学认知亟待提高、生物多样性保护适应气候变化的能力建设不足、自然保护地之间缺乏适应气候变化的生态廊道网络、生物多样性保护适应气候变化的技术标准缺乏。研究提出了中国生物多样性应对气候变化的适应性管理策略,包括制定《中国生物多样性保护协同应对气候变化的国家方案》、加强生物多样性保护适应气候变化的能力建设、开展自然保护区适应气候变化的风险管理试点、强化生物多样性应对气候变化的科技支撑,以期为推进纳入气候变化风险管理的生物多样性保护工作提供决策依据。     

The pace of morphological change: historical transformation of skull shape in St Bernard dogs

Owing to the great morphological diversity of domestic dogs (Canis familiaris), the study of historical shape change in dog skulls provides an excellent opportunity for investigating the dynamics of morphological evolution. Breed standards make known which features were selected by breeders. Here we use the methods of geometric morphometrics to study change of skull shape in a series of purebred St Bernard dogs spanning nearly 120 years. A regression of shape on time was highly significant and revealed a consistent trend of shape change that corresponded to the features deemed desirable by the breed standard. Historical shape change in St Bernards involves a broadening of the skull and a tilting of the palate and upper jaw relative to the rest of the skull. This trend appears to be linear throughout the entire period and appears to be continuing. Allometry was ruled out as a contributing factor to this change because there was no consistent trend of historical change in skull size and because neither the patterns of static nor ontogenetic allometry corresponded to the historical shape change. The dramatic modification of the St Bernard skull demonstrates that selection can achieve sustained and substantial change and can completely overcome constraints such as allometry.     

Finite element scaling analysis of human craniofacial growth

The study of form change is central to traditional cephalometric research. Unfortunately, traditional cephalometric studies operate within systems of measurement that are based on registration and orientation. Measurements produced in registered systems are insufficient for the craniofacial biologist who is interested in locating morphological differences between forms. In this article we apply a registration-free method called finite element scaling analysis in a study of the form change occurring during growth of the normal human craniofacial complex. The method provides form change data that can be summarized at various morphological levels. Twenty normal male individuals are used to analyze the form change that occurs from age 4 to ages 5, 7, 8, 9, 10, 12, 13, and 15 years. The magnitude and direction of growth expressed as shape and size change specific to craniofacial landmarks are presented. Although exceptions occur, our analysis shows that localized size change is, on the average, greater than localized shape change. The relation between size and shape change during growth shows allometry (shape change increasing during growth along with size change) but at a lesser magnitude and slower rate. We conclude that although shape change occurs throughout ontogeny, the magnitude and rate of shape change in relation to size change diminishes as age increases. This analysis represents new insights into the understanding of human craniofacial growth at various levels of morphological integration.     

A new light-induced absorbance change at 561 nm in chloroplasts of green alga, Bryopsis maxima

A new light-induced absorbance change having a maximum at 561nm was discovered in the thalli, as well as in isolated chloroplastsof a green alga, Bryopsis maxima Okamura. Another simultaneous change also occurred at 515 nm. The magnitudeof the 561 nm change was several-fold larger than that at 515nm and much larger than could be explained by an oxidation-reductionchange in cytochromes contained in chloroplasts. There was noabsorbance change in the Soret region that may be correlatedto the 561 nm change. Both 561 and 515 nm changes showed a spike-liketime course pattern, both having a half-rise time of about 20msec. Effects of inhibitors and uncouplers such as DCMU, Cl-CCPand gramicidin J on the absorbance change were also similarat 561 and at 515 nm. We inferred that the 561 nm change is related to photophosphorylationand possibly to the membrane potential in a way similar to the515 nm change. (Received March 27, 1974; )     

Detecting change in an Australian flowering record: Comparisons of linear regression and cumulative sum analysis change point analysis

Linear regression and cumulative sum analysis (CUSUM) change point analyses were used to determine whether there had been a significant change in the first flowering date between 1983 and 2006 for 65 species. Both methods agreed that the first flowering date of 47 species did not change and that eight species had a significant change (P < 0.05) in their flowering. Three species shifted to later flowering and five species to earlier. Over the observation period, each method found that the average shift to later flowering was greater (37.4 days or approx. 1.56 days per year for CUSUM change point analysis and 51.4 days or 2.14 days per year for linear regression) than that to earlier flowering (28.4 days or approx. 1.20 days per year for change point analysis and 46.5 days or 1.97 days per year for linear regression). For the remaining 10 species the results of linear regression and change point methods differed. Each method found five species (three earlier flowering and two later) to have a significantly changed first flowering date over their observation period, where the other method did not. Some of these differences can be attributed to the fact that the CUSUM method can detect multiple change points whereas linear regression can not. Significant change points in first flowering date were identified for 13 species between the years 1987 to 1998. The most frequent year identified as a change point year was 1995. The two methods, although not interchangeable, had strong agreement (84.6%) in detecting shifts. This gives greater confidence that a change in flowering has occurred for eight species and equally importantly, that no change in first flowering date has occurred for 47 species.     

A mathematical consideration for the optimal shell change of hermit crab

Shell of the adult hermit crab has some important roles for its fitness. In the same time, the shell size often limits the body growth of its owner. To grow the body size larger, the individual must change the shell to another larger shell. If the individual cannot get another larger one, the individual has to suppress the body size growth as the occupied shell size allows. Growth suppression would result in the lower fitness. With a simple mathematical model, we consider the criterion about whether the individual should try to change the shell or not in order to get the higher fitness. We show that the optimality of a shell change behavior has a relation with the body size and the season length for the shell change. They also affect the optimal timing for the shell change. It is implied that the probability of the success in a shell change and the cost for the shell change behavior do not affect the optimal timing for the shell change at all but significantly do the optimality of the behavioral choice.     

Climate change‐induced vegetation shifts lead to more ecological droughts despite projected rainfall increases in many global temperate drylands

Drylands occur worldwide and are particularly vulnerable to climate change because dryland ecosystems depend directly on soil water availability that may become increasingly limited as temperatures rise. Climate change will both directly impact soil water availability and change plant biomass, with resulting indirect feedbacks on soil moisture. Thus, the net impact of direct and indirect climate change effects on soil moisture requires better understanding. We used the ecohydrological simulation model SOILWAT at sites from temperate dryland ecosystems around the globe to disentangle the contributions of direct climate change effects and of additional indirect, climate change‐induced changes in vegetation on soil water availability. We simulated current and future climate conditions projected by 16 GCMs under RCP 4.5 and RCP 8.5 for the end of the century. We determined shifts in water availability due to climate change alone and due to combined changes of climate and the growth form and biomass of vegetation. Vegetation change will mostly exacerbate low soil water availability in regions already expected to suffer from negative direct impacts of climate change (with the two RCP scenarios giving us qualitatively similar effects). By contrast, in regions that will likely experience increased water availability due to climate change alone, vegetation changes will counteract these increases due to increased water losses by interception. In only a small minority of locations, climate change‐induced vegetation changes may lead to a net increase in water availability. These results suggest that changes in vegetation in response to climate change may exacerbate drought conditions and may dampen the effects of increased precipitation, that is, leading to more ecological droughts despite higher precipitation in some regions. Our results underscore the value of considering indirect effects of climate change on vegetation when assessing future soil moisture conditions in water‐limited ecosystems.     

Changes in biological source material.

A change in source (or raw) material can be radical, e.g. changing the derivation of a therapeutic protein from human plasma to recombinant DNA manufacture, or the change may be more subtle, e.g. the change from a non-inactivated bovine serum growth supplement to an inactivated serum. The former type of change is usually driven by manufacturing strategy and has vast consequences for the regulation of the product concerned. The latter type of change is usually driven by a need to increase the assurance of viral safety and the regulatory implications for the product are significantly less severe. In this latter example, inadvertent alterations to the product may result from changes in cell metabolism brought about by the change in its growth conditions and these need to be addressed in comparability studies. Ultimately, the implication of any slight change in the fine structure of a biotech medicinal product on its efficacy and/or immunogenicity will have to be dealt with on a case-by-case basis.     

全球变化背景下的现代生态学——第六届现代生态学讲座纪要

"现代生态学讲座"是由著名生态学家李博院士创导,国内外华人生态学家联合发起,旨在促进中国现代生态学与世界同步发展,加强国内外生态学界交流与合作的国际会议。2011年8月1-4日在南京大学举行的第六届现代生态学讲座围绕"全球背景下现代生态学热点问题及其研究进展"主题,进行了23场特邀专家学术讲座,从全球变化背景下:现代生态学方法论、全球变化与陆地生态系统的响应与反馈、全球变化背景下的生物入侵、全球变化背景下的森林生态、全球变化背景下的植物生理生态、全球变化背景下退化生态系统恢复与重建、全球变化背景下的生态水文、全球变化背景下的区域生态管理等八个方面进行分类总结,从不同时空尺度、不同学科角度探讨全球变化与生态系统的响应以及人类为实现可持续发展而采取的适应性管理对策。最后,对会议的进一步完善提出几点建议。     

Neophenogenesis: a developmental theory of phenotypic evolution

An important task for evolutionary biology is to explain how phenotypes change over evolutionary time. Neo-Darwinian theory explains phenotypic change as the outcome of genetic change brought about by natural selection. In the neo-Darwinian account, genetic change is primary; phenotypic change is a secondary outcome that is often given no explicit consideration at all. In this article, we introduce the concept of neophenogenesis: a persistent, transgenerational change in phenotypes over evolutionary time. A theory of neophenogenesis must encompass all sources of such phenotypic change, not just genetic ones. Both genetic and extra-genetic contributions to neophenogenesis have their effect through the mechanisms of development, and developmental considerations, particularly a rejection of the commonly held distinction between inherited and acquired traits, occupy a central place in neophenogenetic theory. New phenotypes arise because of a change in the patterns of organism-environment interaction that produce development in members of a population. So long as these new patterns of developmental interaction persist, the new phenotype(s) will also persist. Although the developmental mechanisms that produce the novel phenotype may change, as in the process known as "genetic assimilation", such changes are not necessary in order for neophenogenesis to occur, because neophenogenetic theory is a theory of phenotypic, not genetic, change.