Macroecology is a subfield in ecology that uses a methodological approach that investigates the empirical patterns and mechanistic processes by which the particulate components of complex ecological systems generate emergent structures and dynamics [1] Unlike traditional ecology, which focuses on local and small-scale interactions, macroecology seeks to identify general emergent patterns within and across spatial and temporal scales.
One of the main tenets of macroecology is that, despite the apparent complexity and randomness of ecological systems, they exhibit a significant degree of order. This order is particularly evident in statistical patterns related to organism interactions, their relationships with the environment, and the emergent structures and dynamics of ecological systems. As put by Brown (1999), [1] "Despite their complexity, ecological systems are not haphazard collections of organisms interacting randomly. Instead, they exhibit a great deal of order: in the kinds of organisms that make up the system, like their interactions with each other and their nonliving environment, and especially in the emergent structure and dynamics of the system. This order is perhaps best revealed in certain statistical patterns." Lawton [2] aptly captures the essence of macroecology: "Macroecology ... seeks to get above the mind‐boggling details of local community assembly to find a bigger picture, whereby a kind of statistical order emerges from the scrum.” Thus, macroecology often aims to elucidate statistical patterns of abundance, distribution, and diversity across different biological scales. [3]
The term "macroecology" was first introduced by Venezuelan researchers Guillermo Sarmiento and Maximina Monasterio in 1971 [4] and was later adopted by James Brown and Brian Maurer in their 1989 paper in Science . [5]
Macroecology is not just a large-scale study; a macroecological approach can also be taken at small scales to study emergent behavior. [1] In essence, macroecology adopts a "top-down" approach, focusing on understanding the properties of entire systems (populations, communities, assemblages etc.) rather than individual components. It is akin to seeing the entire forest instead of individual trees, as Kevin Gaston and Tim Blackburn suggested. [6] Some critical areas of interest within macroecology include the study of species richness, latitudinal gradients in species diversity, the species-area curve, range size, body size, and species abundance. Specifically, the relationship between abundance and range size—exploring why some species are widespread and abundant while others are restricted and less common—has been a focal area of macroecological research. [3] [5]
Ecology is the study of the relationships among living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps with the closely related sciences of biogeography, evolutionary biology, genetics, ethology, and natural history.
Theoretical ecology is the scientific discipline devoted to the study of ecological systems using theoretical methods such as simple conceptual models, mathematical models, computational simulations, and advanced data analysis. Effective models improve understanding of the natural world by revealing how the dynamics of species populations are often based on fundamental biological conditions and processes. Further, the field aims to unify a diverse range of empirical observations by assuming that common, mechanistic processes generate observable phenomena across species and ecological environments. Based on biologically realistic assumptions, theoretical ecologists are able to uncover novel, non-intuitive insights about natural processes. Theoretical results are often verified by empirical and observational studies, revealing the power of theoretical methods in both predicting and understanding the noisy, diverse biological world.
This glossary of ecology is a list of definitions of terms and concepts in ecology and related fields. For more specific definitions from other glossaries related to ecology, see Glossary of biology, Glossary of evolutionary biology, and Glossary of environmental science.
The metabolic theory of ecology (MTE) is the ecological component of the more general Metabolic Scaling Theory and Kleiber's law. It posits that the metabolic rate of organisms is the fundamental biological rate that governs most observed patterns in ecology. MTE is part of a larger set of theory known as metabolic scaling theory that attempts to provide a unified theory for the importance of metabolism in driving pattern and process in biology from the level of cells all the way to the biosphere.
An ecosystem engineer is any species that creates, significantly modifies, maintains or destroys a habitat. These organisms can have a large impact on species richness and landscape-level heterogeneity of an area. As a result, ecosystem engineers are important for maintaining the health and stability of the environment they are living in. Since all organisms impact the environment they live in one way or another, it has been proposed that the term "ecosystem engineers" be used only for keystone species whose behavior very strongly affects other organisms.
Evolutionary ecology lies at the intersection of ecology and evolutionary biology. It approaches the study of ecology in a way that explicitly considers the evolutionary histories of species and the interactions between them. Conversely, it can be seen as an approach to the study of evolution that incorporates an understanding of the interactions between the species under consideration. The main subfields of evolutionary ecology are life history evolution, sociobiology, the evolution of interspecific interactions and the evolution of biodiversity and of ecological communities.
James Hemphill Brown is an American biologist and academic.
Spatial ecology studies the ultimate distributional or spatial unit occupied by a species. In a particular habitat shared by several species, each of the species is usually confined to its own microhabitat or spatial niche because two species in the same general territory cannot usually occupy the same ecological niche for any significant length of time.
Species richness, or biodiversity, increases from the poles to the tropics for a wide variety of terrestrial and marine organisms, often referred to as the latitudinal diversity gradient. The latitudinal diversity gradient is one of the most widely recognized patterns in ecology. It has been observed to varying degrees in Earth's past. A parallel trend has been found with elevation, though this is less well-studied.
Soil ecology is the study of the interactions among soil organisms, and between biotic and abiotic aspects of the soil environment. It is particularly concerned with the cycling of nutrients, formation and stabilization of the pore structure, the spread and vitality of pathogens, and the biodiversity of this rich biological community.
The following outline is provided as an overview of and topical guide to ecology:
In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area at the same time, also known as a biocoenosis, biotic community, biological community, ecological community, or life assemblage. The term community has a variety of uses. In its simplest form it refers to groups of organisms in a specific place or time, for example, "the fish community of Lake Ontario before industrialization".
In ecology, the occupancy–abundance (O–A) relationship is the relationship between the abundance of species and the size of their ranges within a region. This relationship is perhaps one of the most well-documented relationships in macroecology, and applies both intra- and interspecifically. In most cases, the O–A relationship is a positive relationship. Although an O–A relationship would be expected, given that a species colonizing a region must pass through the origin and could reach some theoretical maximum abundance and distribution, the relationship described here is somewhat more substantial, in that observed changes in range are associated with greater-than-proportional changes in abundance. Although this relationship appears to be pervasive, and has important implications for the conservation of endangered species, the mechanism(s) underlying it remain poorly understood
In spatial ecology and macroecology, scaling pattern of occupancy (SPO), also known as the area-of-occupancy (AOO) is the way in which species distribution changes across spatial scales. In physical geography and image analysis, it is similar to the modifiable areal unit problem. Simon A. Levin (1992) states that the problem of relating phenomena across scales is the central problem in biology and in all of science. Understanding the SPO is thus one central theme in ecology.
An ecological network is a representation of the biotic interactions in an ecosystem, in which species (nodes) are connected by pairwise interactions (links). These interactions can be trophic or symbiotic. Ecological networks are used to describe and compare the structures of real ecosystems, while network models are used to investigate the effects of network structure on properties such as ecosystem stability.
Aquatic biodiversity research is the field of scientific research studying marine and freshwater biological diversity.
The body size-species richness distribution is a pattern observed in the way taxa are distributed over large spatial scales. The number of species that exhibit small body size generally far exceed the number of species that are large-bodied. Macroecology has long sought to understand the mechanisms that underlie the patterns of biodiversity, such as the body size-species richness pattern.
Mechanistic models for niche apportionment are biological models used to explain relative species abundance distributions. These niche apportionment models describe how species break up resource pool in multi-dimensional space, determining the distribution of abundances of individuals among species. The relative abundances of species are usually expressed as a Whittaker plot, or rank abundance plot, where species are ranked by number of individuals on the x-axis, plotted against the log relative abundance of each species on the y-axis. The relative abundance can be measured as the relative number of individuals within species or the relative biomass of individuals within species.
Relative species abundance is a component of biodiversity and is a measure of how common or rare a species is relative to other species in a defined location or community. Relative abundance is the percent composition of an organism of a particular kind relative to the total number of organisms in the area. Relative species abundances tend to conform to specific patterns that are among the best-known and most-studied patterns in macroecology. Different populations in a community exist in relative proportions; this idea is known as relative abundance.
In macroecology and community ecology, an occupancy frequency distribution (OFD) is the distribution of the numbers of species occupying different numbers of areas. It was first reported in 1918 by the Danish botanist Christen C. Raunkiær in his study on plant communities. The OFD is also known as the species-range size distribution in literature.
Scientific journals covering macroecology: