Niche construction in the light of niche theory

Ecological niche construction, the process whereby an organism improves its environment to enhance its growth and persistence, is an important missing element of niche theory. Niche theory has mainly focused on niche-deteriorating processes, such as resource consumption, predation and competition, which have negative effects on population growth. Here, we integrate niche construction explicitly into modern niche theory. We use a graphical approach to analyse how a species' niche-improving impacts interplay with niche-deteriorating impacts to modify its response to the environment. In a model of two consumers that compete for one limiting resource and one predator, we show how niche construction modifies the traditional niche-deteriorating impacts of its agent or of competing species, and hence the potential for species coexistence. By altering the balance between intraspecific and interspecific competitive effects, niche construction can either generate net interspecific facilitation or strengthen interspecific competition. The adaptive benefit derived from niche construction also strongly affects the realized niche of a niche-constructing species.     

Plants intertwine fluvial landform dynamics with ecological succession and natural selection: a niche construction perspective for riparian systems

Aim   To contribute to the development of a macroevolutionary framework for riparian systems, reinforcing conceptual linkages between earth surface processes and biological and ecological processes.
Location   Riparian systems.
Methods   Literature review leading to an original proposition for perceiving the functioning of riparian systems in a new and different way.
Results   Riparian systems provide diverse landforms, habitats and resources for animals and plants. Certain organisms, defined as 'ecosystem engineers', significantly create and modify the physical components of riparian systems. Many studies have highlighted such engineering effects by animals on riparian systems, but the identification and understanding of the effects and responses of plants within fluvial corridors have emerged only recently. The modulation of matter, resources and energy flows by engineering plants helps establish characteristic sequences of fluvial landform creation and maintenance associated with synergetic ecological successions. We relate this process to the concept of niche construction, developed mainly by evolutionary biologists. Feedbacks between adaptive responses of riparian plants to flow regime and adjusting effects on biostabilization and bioconstruction are discussed in the context of niche construction at the scale of ecological succession and the evolution of organisms.
Main conclusions   Our conceptualization forges an integrated approach for understanding vegetated fluvial systems from a macroevolutionary perspective, for elucidating riparian ecosystem dynamics and potentially for establishing long-term stream conservation and restoration strategies.     

Compartmentalized organization of ecological niche occupation in insular invertebrate communities

Understanding the mechanisms of species distribution within ecosystems is a fundamental question of ecological research. The current worldwide changes and loss of habitats associated with a decline in species richness render this topic a key element for developing mitigation strategies. Ecological niche theory is a widely accepted concept to describe species distribution along environmental gradients where each taxon occupies its own distinct set of environmental parameters, that is, its niche. Niche occupation has been described in empirical studies for different closely related taxa, like ant, ungulate, or skink species, just to name a few. However, how species assemblages of whole ecosystems across multiple taxa are structured and organized has not been investigated thoroughly, although considering all taxa of a community would be essential when analyzing realized niches. Here, we investigated the organization of niche occupation and species distribution for the whole ground‐associated invertebrate community of small tropical insular ecosystems. By correlating environmental conditions with species occurrences using partial canonical correspondence analysis (pCCA), we demonstrated that the ground‐associated invertebrate community does not spread evenly across the overall niche space, but instead is compartmentalized in four distinct clusters: crustacean and gastropod taxa occurred in one cluster, attributable to the beach habitat, whereas hexapods and spider taxa occurred in three distinct inland clusters, attributable to distinct inland habitats, that is, grassland, open forest, and dense forest. Within the clusters, co‐occurrence pattern analysis suggested only a few negative interactions between the different taxa. By studying ground‐associated insular invertebrate communities, we have shown that species distribution and niche occupation can be, similar to food webs, organized in a compartmentalized way. The compartmentalization of the niche space might thereby be a mechanism to increase ecosystem resilience, as disturbances cascade more slowly throughout the ecosystem.     

Analysing ecological networks of species interactions

Network approaches to ecological questions have been increasingly used, particularly in recent decades. The abstraction of ecological systems – such as communities – through networks of interactions between their components indeed provides a way to summarize this information with single objects. The methodological framework derived from graph theory also provides numerous approaches and measures to analyze these objects and can offer new perspectives on established ecological theories as well as tools to address new challenges. However, prior to using these methods to test ecological hypotheses, it is necessary that we understand, adapt, and use them in ways that both allow us to deliver their full potential and account for their limitations. Here, we attempt to increase the accessibility of network approaches by providing a review of the tools that have been developed so far, with – what we believe to be – their appropriate uses and potential limitations. This is not an exhaustive review of all methods and metrics, but rather, an overview of tools that are robust, informative, and ecologically sound. After providing a brief presentation of species interaction networks and how to build them in order to summarize ecological information of different types, we then classify methods and metrics by the types of ecological questions that they can be used to answer from global to local scales, including methods for hypothesis testing and future perspectives. Specifically, we show how the organization of species interactions in a community yields different network structures (e.g., more or less dense, modular or nested), how different measures can be used to describe and quantify these emerging structures, and how to compare communities based on these differences in structures. Within networks, we illustrate metrics that can be used to describe and compare the functional and dynamic roles of species based on their position in the network and the organization of their interactions as well as associated new methods to test the significance of these results. Lastly, we describe potential fruitful avenues for new methodological developments to address novel ecological questions.     

The geography and ecology of plant speciation: range overlap and niche divergence in sister species

A goal of evolutionary biology is to understand the roles of geography and ecology in speciation. The recent shared ancestry of sister species can leave a major imprint on their geographical and ecological attributes, possibly revealing processes involved in speciation. We examined how ecological similarity, range overlap and range asymmetry are related to time since divergence of 71 sister species pairs in the California Floristic Province (CFP). We found that plants exhibit strikingly different age-range correlation patterns from those found for animals; the latter broadly support allopatric speciation as the primary mode of speciation. By contrast, plant sisters in the CFP were sympatric in 80% of cases and range sizes of sisters differed by a mean of 10-fold. Range overlap and range asymmetry were greatest in younger sisters. These results suggest that speciation mechanisms broadly grouped under ‘budding’ speciation, in which a larger ranged progenitor gives rise to a smaller ranged derivative species, are probably common. The ecological and reproductive similarity of sisters was significantly greater than that of sister–non-sister congeners for every trait assessed. However, shifts in at least one trait were present in 93% of the sister pairs; habitat and soil shifts were especially common. Ecological divergence did not increase with range overlap contrary to expectations under character displacement in sympatry. Our results suggest that vicariant speciation is more ubiquitous in animals than plants, perhaps owing to the sensitivity of plants to fine-scale environmental heterogeneity. Despite high levels of range overlap, ecological shifts in the process of budding speciation may result in low rates of fine-scale spatial co-occurrence. These results have implications for ecological studies of trait evolution and community assembly; despite high levels of sympatry, sister taxa and potentially other close relatives, may be missing from local communities.     

扩散模式对高阶相互作用物种共存机制的影响

物种共存机制是群落生态学研究的核心问题之一,但以成对物种间直接相互作用为主的传统共存理论,并未在实际群落中得到普遍证实。近年来,有研究表明,高阶相互作用,即一个物种对另一个物种的直接作用强度受到其他物种的间接影响,在群落竞争过程中的重要性不断得到发展。目前,对高阶相互作用的理论研究还主要集中在非空间理论模型。事实上,群落中个体的空间分布和扩散模式等对种群动态的影响均至关重要。故考虑空间因素,以三物种为例构建空间显式的群落动态模拟,通过引入不同的物种扩散模式,研究高阶相互作用对群落物种共存结果的影响。研究表明:(1)高阶相互作用可以促进也可能抑制物种共存,具体共存结果取决于高阶相互作用的方向、强度和分类;(2)当全部高阶相互作用都存在,且取值为正时,物种共存位置会发生偏移,原本生态位分化下共存的区域不再共存,而在生态位重叠度较高的区域,物种可以在更大范围的适合度差异下共存;(3)扩散模式对高阶相互作用的上述调节机制有一定的影响,且无论正高阶还是负高阶,当种群趋于局部扩散时,高阶相互作用的正向及负向调节效果均有所减弱。以上结论强调了在理论模型和实际保护工作中考虑相互作用网络的重要性,有助于进一步理解物种共存机制,能够为保护生物多样性提供理论依据。     

珊瑚礁区的生物多样性及其生态功能

珊瑚礁区生物多样性程度可以与陆地热带雨林相提并论,目前关于珊瑚礁物种多样性及其空间分布特征方面研究进展迅速,是生物多样性研究的重要基地。作为一种生态资源,珊瑚礁还具有重要的生态功能,近年来由于全球气候逐渐变暖、人类活动影响不断加剧,导致其生物多样性缩减、生态功能严重退化。珊瑚礁生态系统多样性、遗传多样性已成为珊瑚礁研究热点,珊瑚礁生态环境效应和保护管理方面的研究也越来越受到重视。我国珊瑚礁主要分布在广阔的南海海域和海南岛、台湾岛、香港和广东广西沿岸,礁区生物种类繁多,多样性程度较高,以往研究主要涉及地质、地貌、生物、环境等方面,现今和今后一段时间里迫切需要加强生物多样性和生态功能研究,以确保更有效地保护和管理珊瑚礁。     

Linking biodiversity and ecosystems: towards a unifying ecological theory

Community ecology and ecosystem ecology provide two perspectives on complex ecological systems that have largely complementary strengths and weaknesses. Merging the two perspectives is necessary both to ensure continued scientific progress and to provide society with the scientific means to face growing environmental challenges. Recent research on biodiversity and ecosystem functioning has contributed to this goal in several ways. By addressing a new question of high relevance for both science and society, by challenging existing paradigms, by tightly linking theory and experiments, by building scientific consensus beyond differences in opinion, by integrating fragmented disciplines and research fields, by connecting itself to other disciplines and management issues, it has helped transform ecology not only in content, but also in form. Creating a genuine evolutionary ecosystem ecology that links the evolution of species traits at the individual level, the dynamics of species interactions, and the overall functioning of ecosystems would give new impetus to this much-needed process of unification across ecological disciplines. Recent community evolution models are a promising step in that direction.     

The mathematical influence on global patterns of biodiversity

Although we understand how species evolve, we do not appreciate how this process has filled an empty world to create current patterns of biodiversity. Here, we conduct a numerical experiment to determine why biodiversity varies spatially on our planet. We show that spatial patterns of biodiversity are mathematically constrained and arise from the interaction between the species’ ecological niches and environmental variability that propagates to the community level. Our results allow us to explain key biological observations such as (a) latitudinal biodiversity gradients (LBGs) and especially why oceanic LBGs primarily peak at midlatitudes while terrestrial LBGs generally exhibit a maximum at the equator, (b) the greater biodiversity on land even though life first evolved in the sea, (c) the greater species richness at the seabed than at the sea surface, and (d) the higher neritic (i.e., species occurring in areas with a bathymetry lower than 200 m) than oceanic (i.e., species occurring in areas with a bathymetry higher than 200 m) biodiversity. Our results suggest that a mathematical constraint originating from a fundamental ecological interaction, that is, the niche–environment interaction, fixes the number of species that can establish regionally by speciation or migration.     

No species is an island: testing the effects of biotic interactions on models of avian niche occupation

Traditionally, the niche of a species is described as a hypothetical 3D space, constituted by well‐known biotic interactions (e.g. predation, competition, trophic relationships, resource–consumer interactions, etc.) and various abiotic environmental factors. Species distribution models (SDMs), also called “niche models” and often used to predict wildlife distribution at landscape scale, are typically constructed using abiotic factors with biotic interactions generally been ignored. Here, we compared the goodness of fit of SDMs for red‐backed shrike Lanius collurio in farmlands of Western Poland, using both the classical approach (modeled only on environmental variables) and the approach which included also other potentially associated bird species. The potential associations among species were derived from the relevant ecological literature and by a correlation matrix of occurrences. Our findings highlight the importance of including heterospecific interactions in improving our understanding of niche occupation for bird species. We suggest that suite of measures currently used to quantify realized species niches could be improved by also considering the occurrence of certain associated species. Then, an hypothetical “species 1” can use the occurrence of a successfully established individual of “species 2” as indicator or “trace” of the location of available suitable habitat to breed. We hypothesize this kind of biotic interaction as the “heterospecific trace effect” (HTE): an interaction based on the availability and use of “public information” provided by individuals from different species. Finally, we discuss about the incomes of biotic interactions for enhancing the predictive capacities on species distribution models.     

不同生态恢复方式下生态系统服务与生物多样性恢复效果的整合分析

全球范围内关键生态系统服务的减少使人类社会面临巨大的威胁,生物多样性是生态系统提供各种产品和服务的基础。生态恢复工程对退化的生态系统服务和生物多样性进行修复,对于缓解人类环境压力具有非常重要的意义。长期的理论和实践工作形成了多种生态恢复措施:(1)单纯基于生态系统自我设计的自然恢复方式,(2)人为设计对环境条件进行干预,反馈影响生态系统的自我设计,(3)人为设计对目标种群和生态系统进行直接干预和重建。这3类恢复方式可以在不同程度上定向的影响生态系统的恢复进程,反映了人类对生态系统的低度、中度和高度介入。哪种恢复方式和介入程度能够实现更好的恢复效果,是生态恢复学中的一个关键问题,但到目前为止,虽广有争议,却无定量的分析和结论。针对这个空白,通过对ISI Web of Knowledge数据库中生态恢复相关文献的整合分析,基于数学统计的方法定量比较在不同条件下低度介入(自然恢复)、中度介入(环境干预)和高度介入(直接干预)3种恢复方式对生态系统服务与生物多样性的恢复效果。论文从4个方面展开研究:(1)低度、中度、高度介入生态恢复方式的划分,(2)比较3大类介入方式对生态系统服务和生物多样性恢复效果的差异,(3)不同气候条件、生态系统类型和恢复时间等背景因素的影响,(4)生物多样性恢复和生态系统服务恢复之间的关系。研究结果揭示了不同生态恢复方式的适用条件,以及对生物多样性和生态系统恢复相互关系的作用,对生态恢复实践中恢复方式的选择有指导作用。对未来的研究也有启示意义,如针对特定生态系统服务或具体研究问题进一步探索低度、中度和高度介入生态恢复方式的作用规律和机制;将地区的社会经济水平、生态系统的受损程度等因素纳入生态恢复方式的考察,以最优化生态恢复成本-效率等。     

基于生态位构建的n-种群集合种群动态分析

生态位构建是指任何有机体具有的对环境的修复作用,其可能对集合种群的动态与分布产生深刻的影响.尝试性的将生态位构建概念引入集合种群的续存与动态这一复杂问题的研究中,建立了具有生态位构建作用的多物种集合种群的数学模型.模拟结果表明:随着生态位构建能力的增强,种群的续存能力和平衡态大小都有所增加;在此过程中,生态序的变化具有一定的规律性,分别呈现灭绝数为零的 1、 3、 5、 7和 9的协同演化.     

Eco-evolutionary feedbacks in community and ecosystem ecology: interactions between the ecological theatre and the evolutionary play

Interactions between natural selection and environmental change are well recognized and sit at the core of ecology and evolutionary biology. Reciprocal interactions between ecology and evolution, eco-evolutionary feedbacks, are less well studied, even though they may be critical for understanding the evolution of biological diversity, the structure of communities and the function of ecosystems. Eco-evolutionary feedbacks require that populations alter their environment (niche construction) and that those changes in the environment feed back to influence the subsequent evolution of the population. There is strong evidence that organisms influence their environment through predation, nutrient excretion and habitat modification, and that populations evolve in response to changes in their environment at time-scales congruent with ecological change (contemporary evolution). Here, we outline how the niche construction and contemporary evolution interact to alter the direction of evolution and the structure and function of communities and ecosystems. We then present five empirical systems that highlight important characteristics of eco-evolutionary feedbacks: rotifer–algae chemostats; alewife–zooplankton interactions in lakes; guppy life-history evolution and nutrient cycling in streams; avian seed predators and plants; and tree leaf chemistry and soil processes. The alewife–zooplankton system provides the most complete evidence for eco-evolutionary feedbacks, but other systems highlight the potential for eco-evolutionary feedbacks in a wide variety of natural systems.     

Physiology in ecological niche modeling: using zebra mussel's upper thermal tolerance to refine model predictions through Bayesian analysis

Climate change and human-mediated dispersal are increasingly influencing species’ geographic distributions. Ecological niche models (ENMs) are widely used in forecasting species’ distributions, but are weak in extrapolation to novel environments because they rely on available distributional data and do not incorporate mechanistic information, such as species’ physiological response to abiotic conditions. To improve accuracy of ENMs, we incorporated physiological knowledge through Bayesian analysis. In a case study of the zebra mussel Dreissena polymorpha, we used native and global occurrences to obtain native and global models representing narrower and broader understanding of zebra mussel’ response to temperature. We also obtained thermal limit and survival information for zebra mussel from peer-reviewed literature and used the two types of information separately and jointly to calibrate native models. We showed that, compared to global models, native models predicted lower relative probability of presence along zebra mussel's upper thermal limit, suggesting the shortcoming of native models in predicting zebra mussel's response to warm temperature. We also found that native models showed improved prediction of relative probability of presence when thermal limit was used alone, and best approximated global models when both thermal limit and survival data were used. Our result suggests that integration of physiological knowledge enhances extrapolation of ENM in novel environments. Our modeling framework can be generalized for other species or other physiological limits and may incorporate evolutionary information (e.g. evolved thermal tolerance), thus has the potential to improve predictions of species’ invasive potential and distributional response to climate change.     

Predicting the distribution of Sasquatch in western North America: anything goes with ecological niche modelling

The availability of user-friendly software and publicly available biodiversity databases has led to a rapid increase in the use of ecological niche modelling to predict species distributions. A potential source of error in publicly available data that may affect the accuracy of ecological niche models (ENMs), and one that is difficult to correct for, is incorrect (or incomplete) taxonomy. Here we remind researchers of the need for careful evaluation of database records prior to use in modelling, especially when the presence of cryptic species is suspected or many records are based on indirect evidence. To draw attention to this potential problem, we construct ENMs for the North American Sasquatch (i.e. Bigfoot). Specifically, we use a large database of georeferenced putative sightings and footprints for Sasquatch in western North America, demonstrating how convincing environmentally predicted distributions of a taxon's potential range can be generated from questionable site-occurrence data. We compare the distribution of Bigfoot with an ENM for the black bear, Ursus americanus , and suggest that many sightings of this cryptozoid may be cases of mistaken identity.     

Measuring ecological niche overlap from occurrence and spatial environmental data

Aim Concerns over how global change will influence species distributions, in conjunction with increased emphasis on understanding niche dynamics in evolutionary and community contexts, highlight the growing need for robust methods to quantify niche differences between or within taxa. We propose a statistical framework to describe and compare environmental niches from occurrence and spatial environmental data. Location Europe, North America and South America. Methods The framework applies kernel smoothers to densities of species occurrence in gridded environmental space to calculate metrics of niche overlap and test hypotheses regarding niche conservatism. We use this framework and simulated species with pre‐defined distributions and amounts of niche overlap to evaluate several ordination and species distribution modelling techniques for quantifying niche overlap. We illustrate the approach with data on two well‐studied invasive species. Results We show that niche overlap can be accurately detected with the framework when variables driving the distributions are known. The method is robust to known and previously undocumented biases related to the dependence of species occurrences on the frequency of environmental conditions that occur across geographical space. The use of a kernel smoother makes the process of moving from geographical space to multivariate environmental space independent of both sampling effort and arbitrary choice of resolution in environmental space. However, the use of ordination and species distribution model techniques for selecting, combining and weighting variables on which niche overlap is calculated provide contrasting results. Main conclusions The framework meets the increasing need for robust methods to quantify niche differences. It is appropriate for studying niche differences between species, subspecies or intra‐specific lineages that differ in their geographical distributions. Alternatively, it can be used to measure the degree to which the environmental niche of a species or intra‐specific lineage has changed over time.     

Burrow webs: Clawing the surface of interactions with burrows excavated by American badgers

Ecosystem engineers are organisms that influence their environment, which includes alterations leading to habitat provisioning for other species. Perhaps the most well‐examined guild of species provisioning habitat for other species is tree cavity excavators or woodpeckers (Picidae). Many studies have examined the suite of secondary cavity users that rely on woodpeckers, and how the ecological network of secondary users, collectively referred to as the nest web, changes across communities. Despite similar habitat provisioning processes, fewer studies have assessed the suite of species associated with burrowers providing access to subterranean habitat. Here, we begin to characterize the burrow web provisioned by American badgers (Taxidea taxus) and evaluate the diversity and frequency of species interactions we detected at abandoned badger burrows in Wyoming, USA. We deployed camera traps at 23 badger burrows and identified interactions with the burrow by birds, mammals, and reptiles. Overall, we discovered 31 other species utilizing badger burrows, consisting of 12 mammals, 18 birds, and 1 reptile. Mammals, other than American badgers themselves and other fossorial species such as ground squirrels (Urocitellus sp.), frequently using burrows included mice (Peromyscus sp.), long‐tailed weasel (Mustela frenata), pygmy rabbit (Brachylagus idahoensis), and desert cottontail (Sylvilagus audubonii). Of the 18 bird species detected, most accounted for <5% of overall detections, besides chipping sparrows (Spizella passerina) at 7.2%–11.5% of detections. The most common category of detection by bird species was foraging, contrary to mammals, which used the burrow frequently and were commonly observed entering and exiting the burrow. This work provides additional context on the ecological role of American badgers within their environment. More broadly, this work scratches the surface of many remaining questions to explore with the aim of advancing our understandings about burrow webs across the diversity of burrowing species and the communities in which they occur.