Evolutionary suicide

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Evolutionary suicide is an evolutionary phenomenon in which the process of adaptation causes the population to become extinct. For example, individuals might be selected to switch from eating mature plants to seedlings, and thereby deplete their food plant's population. Selection on individuals can theoretically produce adaptations that threaten the survival of the population.

Adaptation Trait with a current functional role in the life history of an organism maintained and evolved by natural selection

In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection.

Much of the research on evolutionary suicide has used the mathematical modeling technique adaptive dynamics, in which genetic changes are studied together with population dynamics. This allows the model to predict how population density will change as a given trait invades the population.

A mathematical model is a description of a system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modeling. Mathematical models are used in the natural sciences and engineering disciplines, as well as in the social sciences.

Population dynamics the branch of life sciences studying changes in the size and age composition of populations

Population dynamics is the branch of life sciences that studies the size and age composition of populations as dynamical systems, and the biological and environmental processes driving them. Example scenarios are ageing populations, population growth, or population decline.

Population density A measurement of population numbers per unit area or volume

Population density is a measurement of population per unit area or unit volume; it is a quantity of type number density. It is frequently applied to living organisms, and most of the time to humans. It is a key geographical term. In simple terms population density refers to the number of people living in an area per kilometer square.

Evolutionary suicide has also been referred to as "Darwinian extinction", "runaway selection to self-extinction", and "evolutionary collapse".[ citation needed ] The idea is similar in concept to the tragedy of the commons and the Tendency of the rate of profit to fall, namely that they are all examples of an accumulation of individual changes leading to a collective disaster such that it negates those individual changes.

Tragedy of the commons A theoretical concept concerning the allocation of shared, open access resources

The tragedy of the commons is a term used in environmental science to describe a situation in a shared-resource system where individual users acting independently according to their own self-interest behave contrary to the common good of all users by depleting or spoiling that resource through their collective action. The concept originated in an essay written in 1833 by the British economist William Forster Lloyd, who used a hypothetical example of the effects of unregulated grazing on common land in Great Britain and Ireland. The concept became widely known as the "tragedy of the commons" over a century later due to an article written by the American ecologist and philosopher Garrett Hardin in 1968. In this modern economic context, commons is taken to mean any shared and unregulated resource such as atmosphere, oceans, rivers, fish stocks, roads and highways, or even an office refrigerator.

The tendency of the rate of profit to fall (TRPF) is a hypothesis in economics and political economy, most famously expounded by Karl Marx in chapter 13 of Capital, Volume III. Economists as diverse as Adam Smith, John Stuart Mill, David Ricardo and Stanley Jevons referred explicitly to the TRPF as an empirical phenomenon that demanded further theoretical explanation, yet they each differed as to the reasons why the TRPF should necessarily occur.

Many adaptations have apparently negative effects on population dynamics, for example infanticide by male lions, or the production of toxins by bacteria. However, empirically establishing that an extinction event was unambiguously caused by the process of adaptation is not a trivial task.

See also

<i>The Limits to Growth</i> book

The Limits to Growth (LTG) is a 1972 report on the computer simulation of exponential economic and population growth with a finite supply of resources. Funded by the Volkswagen Foundation and commissioned by the Club of Rome, the findings of the study were first presented at international gatherings in Moscow and Rio de Janeiro in the summer of 1971. The report's authors are Donella H. Meadows, Dennis L. Meadows, Jørgen Randers, and William W. Behrens III, representing a team of 17 researchers.

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