Evolutionary ecology lies at the intersection of

ecology Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overl ...

and

evolutionary biology Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life ...

. 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 Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

of social behavior), the evolution of interspecific interactions (e.g. cooperation, predator–prey interactions,

parasitism Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

, mutualism) and the evolution of

biodiversity Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic ('' genetic variability''), species ('' species diversity''), and ecosystem ('' ecosystem diversity'') ...

and of

ecological communities 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 ...

. Evolutionary ecology mostly considers two things: how interactions (both among species and between species and their physical environment) shape species through selection and adaptation, and the consequences of the resulting evolutionary change.

Evolutionary models

A large part of evolutionary ecology is about utilising models and finding empirical data as proof. Examples include the Lack clutch size model devised by David Lack and his study of

Darwin's finches Darwin's finches (also known as the Galápagos finches) are a group of about 18 species of passerine birds. They are well known for their remarkable diversity in beak form and function. They are often classified as the subfamily Geospizinae or ...

on the Galapagos Islands. Lack's study of Darwin's finches was important in analyzing the role of different ecological factors in speciation. Lack suggested that differences in species were adaptive and produced by

natural selection Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Cha ...

, based on the assertion by G.F. Gause that two species cannot occupy the same niche. Richard Levins introduced his model of the specialization of species in 1968, which investigated how habitat specialization evolved within heterogeneous environments using the fitness sets an organism or species possesses. This model developed the concept of spatial scales in specific environments, defining fine-grained spatial scales and coarse-grained spatial scales. The implications of this model include a rapid increase in environmental ecologists' understanding of how spatial scales impact species diversity in a certain environment. Another model is Law and Diekmann's 1996 models on mutualism, which is defined as a relationship between two organisms that benefits both individuals. Law and Diekmann developed a framework called adaptive dynamics, which assumes that changes in plant or animal populations in response to a disturbance or lack thereof occurs at a faster rate than mutations occur. It is aimed to simplify other models addressing the relationships within communities.

Tangled nature model

The tangled nature model provides different methods for demonstrating and predicting trends in evolutionary ecology. The model analyzes an individual prone to

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, m ...

within a population as well as other factors such as extinction rate. The model was developed by Simon Laird, Daniel Lawson, and Henrik Jeldtoft Jensen of the Imperial College London in 2002. The purpose of the model is to create a simple and logical ecological model based on observation. The model is designed such that ecological effects can be accounted for when determining form, and fitness of a population.

Ecological genetics

Ecological genetics tie into evolutionary ecology through the study of how traits evolve in natural populations. Ecologists are concerned with how the environment and timeframe leads to genes becoming dominant. Organisms must continually adapt in order to survive in natural habitats. Genes define which organisms survive and which will die out. When organisms develop different genetic variations, even though they stem from the same species, it is known as polymorphism. Organisms that pass on beneficial genes continue to evolve their species to have an advantage inside of their niche.

Evolutionary ecologists

Charles Darwin

The basis of the central principles of evolutionary ecology can be attributed to

Charles Darwin Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended ...

(1809–1882), specifically in referencing his theory of

and population dynamics, which discusses how populations of a species change over time. According to Ernst Mayr, professor of Zoology at Harvard University, Darwin’s most distinct contributions to evolutionary biology and ecology are as follows: “The first is the non-constancy of species, or the modern conception of

itself. The second is the notion of branching evolution, implying the common descent of all species of living things on earth from a single unique origin.” Additionally, “Darwin further noted that evolution must be gradual, with no major breaks or discontinuities. Finally, he reasoned that the mechanism of evolution was natural selection.”

George Evelyn Hutchinson

George Evelyn Hutchinson’s (1903–1991) contributions to the field of ecology spanned over 60 years, in which he had significant influence in systems ecology, radiation ecology,

limnology Limnology ( ; from Greek λίμνη, ''limne'', "lake" and λόγος, ''logos'', "knowledge") is the study of inland aquatic ecosystems. The study of limnology includes aspects of the biological, chemical, physical, and geological characteris ...

, and

entomology Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as ara ...

. Described as the “father of modern ecology” by

Stephen Jay Gould Stephen Jay Gould (; September 10, 1941 – May 20, 2002) was an American paleontologist, evolutionary biologist, and historian of science. He was one of the most influential and widely read authors of popular science of his generation. Goul ...

, Hutchinson was one of the first scientists to link the subjects of ecology and mathematics. According to Hutchinson, he constructed “mathematical models of populations, the changing proportions of individuals of various ages, birthrate, the

ecological niche In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for ...

, and population interaction in this technical introduction to population ecology.” He also had a vast interest in limnology, due to his belief that lakes could be studied as a

microcosm Microcosm or macrocosm, also spelled mikrokosmos or makrokosmos, may refer to: Philosophy * Microcosm–macrocosm analogy, the view according to which there is a structural similarity between the human being and the cosmos Music * Macrocosm (al ...

that provides insight into system behavior. Hutchinson is also known for his work Circular Casual Systems in Ecology, in which he states that “groups of organisms may be acted upon by their environment, and they may react upon it. If a set of properties in either system changes in such a way that the action of the first system on the second changes, this may cause changes in properties of the second system which alter the mode of action of the second system on the first.”

Robert MacArthur

Robert MacArthur (1930–1972) is best known in the field of Evolutionary Ecology for his work '' The Theory of Island Biogeography'', in which he and his co-author propose “that the number of species on any island reflects a balance between the rate at which new species colonize it and the rate at which populations of established species become

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

.”

Eric Pianka

According to the University of Texas, Eric Pianka’s (1939–present) work in evolutionary ecology includes foraging strategies, reproductive tactics, competition and niche theory, community structure and organization, species diversity, and understanding rarity. Pianka is also known for his interest in lizards to study ecological occurrences, as he claimed they were “often abundant, making them relatively easy to locate, observe, and capture.”

Michael Rosenzweig

Michael L. Rosenzweig (1941–present) created and popularized Reconciliation ecology, which began with his theory that designated nature preserves would not be enough land to conserve the

of Earth, as humans have used so much land that they have negatively impacted biogeochemical cycles and had other ecological impacts that have negatively affected species compositions.

Other notable evolutionary ecologists

R. A. Fisher Sir Ronald Aylmer Fisher (17 February 1890 – 29 July 1962) was a British polymath who was active as a mathematician, statistician, biologist, geneticist, and academic. For his work in statistics, he has been described as "a genius who a ...

(1890–1962), whose 1930 fundamental theorem of natural selection recognised the power of rigorous application of the theory of natural selection to population biology. * David Lack (1910–1973), a follower of

, worked to merge the fields of

and

, focusing mainly on birds and

. *

Thierry Lodé Thierry Lodé (born 1956 in Tarbes) is a French biologist and professor of evolutionary ecology in a CNRS lab at the University of Rennes 1. His work deals mainly with sexual conflict.Göran Arnqvist and Locke Rowe, Eds., "Sexual conflict", Prin ...

(1956–present), a French ecologist whose work focused on how sexual conflict in populations of species impacts evolution.

Research

Michael Rosenzweig's idea of reconciliation ecology was developed based on existing research, which was conducted on the principle first suggested by

Alexander von Humboldt Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 17696 May 1859) was a German polymath, geographer, naturalist, explorer, and proponent of Romantic philosophy and science. He was the younger brother of the Prussian minister ...

stating that larger areas of land will have increased species diversity as compared to smaller areas. This research focused on species-area relationships (SPARs) and the different scales on which they exist, ranging from sample-area to interprovincial SPARs. Steady-state dynamics in diversity gave rise to these SPARs, which are now used to measure the reduction of species diversity on Earth. In response to this decline in diversity, Rosenzweig's reconciliation ecology was born. Evolutionary ecology has been studied using symbiotic relationships between organisms to determine the evolutionary forces by which such relationships develop. In symbiotic relationships, the symbiont must confer some advantage to its host in order to persist and continue to be evolutionarily viable. Research has been conducted using aphids and the symbiotic bacteria with which they coevolve. These bacteria are most frequently conserved from generation to generation, displaying high levels of vertical transmission. Results have shown that these symbiotic bacteria ultimately confer some resistance to parasites to their host aphids, which both increases the fitness of the aphids and lead to symbiont-mediated coevolution between the species.

Color variation in cichlid fish

The effects of evolutionary ecology and its consequences can be seen in the case of color variation among African cichlid fish. With over 2,000 species, cichlid fishes are very species-rich and capable of complex social interactions. Polychromatism, the variation of color patterns within a population, occurs within cichlid fishes due to environmental adaptations and to increase chances of sexual reproduction.