Evolution, theory of

2018 ◽  
Author(s):  
Elisabeth A. Lloyd
Keyword(s):  
Natural Selection ◽  
Evolutionary Theory ◽  
Life Forms ◽  
Genetic Mutation ◽  
Theory Of Evolution ◽  
Selection Processes ◽  
Wide Range ◽  
In The Wild ◽  
Forms Of Life ◽  
The Public Sphere

The biological theory of evolution advances the view that the variety and forms of life on earth are the result of descent with modification from the earliest forms of life. Evolutionary theory does not attempt to explain the origin of life itself, that is, how the earliest forms of life came to exist, nor does it apply to the history of changes of the non-biological parts of the universe, which are also often described as ’evolutionary’. The mechanisms of natural selection, mutation and speciation are used in evolutionary theory to explain the relations and characteristics of all life forms. Modern evolutionary theory explains a wide range of natural phenomena, including the deep resemblances among organisms, the diversity of life forms, organisms’ possession of vestigial organs and the good fit or ’adaptedness’ between organisms and their environment. Often summarized as ’survival of the fittest’, the mechanism of natural selection actually includes several distinct processes. There must be variation in traits among the members of a population; these traits must be passed on from parents to offspring; and the different traits must confer differential advantage for reproducing successfully in that environment. Because evidence for each of these processes can be gathered independently of the evolutionary claim, natural selection scenarios are robustly testable. When a trait in a population has arisen because it was directly selected in this fashion, it is called an adaptation. Genetic mutation is the originating source of variation, and selection processes shape that variation into adaptive forms; random genetic drift and various levels and forms of selection dynamic developed by geneticists have been integrated into a general theory of evolutionary change that encompasses natural selection and genetic mutation as complementary processes. Detailed ecological studies are used to provide evidence for selection scenarios involving the evolution of species in the wild. Evolutionary theory is supported by an unusually wide range of scientific evidence, gaining its support from fields as diverse as geology, embryology, molecular genetics, palaeontology, climatology and functional morphology. Because of tensions between an evolutionary view of homo sapiens and some religious beliefs, evolutionary theory has remained controversial in the public sphere far longer than no less well-supported scientific theories from other sciences.

Darwinian Evolutionary Theory

2018 ◽  
Author(s):  
Michael Ruse
Keyword(s):  
Sexual Selection ◽  
Natural Selection ◽  
Middle Class ◽  
Evolutionary Theory ◽  
Scientific Community ◽  
Homo Sapiens ◽  
Origin Of Species ◽  
Theory Of Evolution ◽  
Descent Of Man

Charles Robert Darwin, the English naturalist, published On the Origin of Species in 1859 and the follow-up work The Descent of Man in 1871. In these works, he argued for his theory of evolution through natural selection, applying it to all organisms, living and dead, including our own species, Homo sapiens. Although controversial from the start, Darwin’s thinking was deeply embedded in the culture of his day, that of a middle-class Englishman. Evolution as such was an immediate success in scientific circles, but although the mechanism of selection had supporters in the scientific community (especially among those working with fast-breeding organisms), its real success was in the popular domain. Natural selection, and particularly the side mechanism of sexual selection, were known to all and popular themes in fiction and elsewhere.

Cooperation, Coordination, and Collective Action

2012 ◽  
Author(s):  
Lee Cronk ◽  
Beth L. Leech
Keyword(s):  
Natural Selection ◽  
Collective Action ◽  
Political Science ◽  
Empirical Research ◽  
Evolutionary Theory ◽  
Coordination Problems ◽  
Evolutionary Biologist ◽  
Wide Range ◽  
Two Bodies

This book investigates a wide range of ideas, theories, and existing empirical research relevant to the study of the complex and diverse phenomenon of human cooperation. Issues relating to cooperation are examined from the perspective of evolutionary theory, political science, and related social sciences. The book draws upon two bodies of work: Mancur Olson's The Logic of Collective Action (1965) and George C. Williams's Adaptation and Natural Selection (1966). Olson, an economist, and Williams, an evolutionary biologist, both argued that a focus on groups would not provide a complete understanding of collective action and other social behaviors. This introductory chapter discusses some important definitions relating to cooperation, with particular emphasis on collective action and collective action dilemmas, along with coordination and coordination problems. It also provides an overview of the chapters that follow.

Introduction to general discussion

1979 ◽  
Vol 205 (1161) ◽  
pp. 599-604 ◽  
Keyword(s):  
Natural Selection ◽  
Evolutionary Theory ◽  
Energy Use ◽  
Limited Resource ◽  
In The Wild ◽  
The Subject ◽  
The One ◽  
Games Theory ◽  
Natural Histories ◽  
Behavioural Strategies

Having heard the papers given at this discussion meeting, one must agree that, whether or not one accepts all details of every statement made, there has been in the last 20 years a vast advancein evolutionary comprehension, associated partic­ularly with advances in molecular biology, the theory of group selection, and the application of games theory to much of animal behaviour. On the one hand, our understanding of the nature of the inception of genetic variation has increased out of all recognition; on the other, numbers of phenomena which formerly were the subject of oleographed colour-plates showing ‘bizarre habits’ or ‘outlandish structures’ in popular natural histories are now brought into general theories which give us the means of asking answerable questions about them, and even making predictions. All of this greatly extends the scope of evolutionary theory. There is, however, one major field of enquiry not mentioned by Maynard Smith - rightly, since it has had as yet very little influence on evolutionary theory - and that is natural selection as it actually goes on in the wild. Much of the work we have heard about at this meeting implies natural selection. If it can be shown that of different behavioural strategies directed to the same goal one is more efficient than the others, in expenditure of energy, use of a limited resource, or in resistance to the introduction of other strategies, then the others are less well adapted in these respects and may be expected to be selected out. In general, any demonstration of function implies the possibility of malfunction and the probability of selection acting to keep that function efficient. In some behavioural situations, the implied selection may be intense. A cock robin that is not sufficiently aggressive will not hold a territory and will not breed; but equally, if it is a little too aggressive and drives off both cocks and hens, it will hold a territory but will still not breed. Similarly, in Tinbergen’s remarkable study of eggshell removal in gulls, taking too long away from the nest in removing the shell may leave the chick a prey to neighbour gulls. But staying to protect them and leaving the broken shell in the nest may mean that it is visible to predators, who then kill the chick. In such examples as these, selection against inappropriate behaviour may be from 50 to 100%, and no population geneticist could doubt the efficacy of such a strength.

scholarly journals Turbulence explains the accelerations of an eagle in natural flight

2021 ◽  
Vol 118 (23) ◽  
pp. e2102588118
Author(s):  
Kasey M. Laurent ◽  
Bob Fogg ◽  
Tobias Ginsburg ◽  
Casey Halverson ◽  
Michael J. Lanzone ◽  
...  
Keyword(s):  
Large Scale ◽  
Power Spectra ◽  
Life Forms ◽  
Flight Behavior ◽  
Avian Behavior ◽  
Avian Flight ◽  
Turbulent Environments ◽  
Wide Range ◽  
In The Wild ◽  
Atmospheric Phenomena

Turbulent winds and gusts fluctuate on a wide range of timescales from milliseconds to minutes and longer, a range that overlaps the timescales of avian flight behavior, yet the importance of turbulence to avian behavior is unclear. By combining wind speed data with the measured accelerations of a golden eagle (Aquila chrysaetos) flying in the wild, we find evidence in favor of a linear relationship between the eagle’s accelerations and atmospheric turbulence for timescales between about 1/2 and 10 s. These timescales are comparable to those of typical eagle behaviors, corresponding to between about 1 and 25 wingbeats, and to those of turbulent gusts both larger than the eagle’s wingspan and smaller than large-scale atmospheric phenomena such as convection cells. The eagle’s accelerations exhibit power spectra and intermittent activity characteristic of turbulence and increase in proportion to the turbulence intensity. Intermittency results in accelerations that are occasionally several times stronger than gravity, which the eagle works against to stay aloft. These imprints of turbulence on the bird’s movements need to be further explored to understand the energetics of birds and other volant life-forms, to improve our own methods of flying through ceaselessly turbulent environments, and to engage airborne wildlife as distributed probes of the changing conditions in the atmosphere.

Ethical Objections to Evolution in Contemporary Muslim Thought

2010 ◽  
Vol 27 (3) ◽  
pp. 79-92
Author(s):  
David Jalajel
Keyword(s):  
Natural Selection ◽  
Reproductive Success ◽  
Evolutionary Theory ◽  
Ethical Behavior ◽  
Human Beings ◽  
Islamic Theology ◽  
Theory Of Evolution ◽  
Ethical Norms ◽  
Differential Reproductive Success ◽  
Survival Of The Fittest

Muslim creationists often argue that the theory of evolution is inherently unethical, claiming that concepts such as natural selection, survival of the fittest, and differential reproductive success promote behaviors like selfishness, violence, and sex- ual promiscuity. This article explores the distinctions made by classical Islamic theologians between God’s actions and human- ity’s actions and their potential to address ethical objections to evolution. The question is examined with reference to two theological traditions: the Ash`ari and the Salafi. The first one distinguishes between God’s creation of actions and humanity’s acquisition (kasab) of actions. According to this approach, ethical valuation is understood to be an attribute of human volitional action. The second approach, followed by Ibn Taymiyyah, Ibn al-Qayyim, Ibn Abu al-`Izz, and others of the so-called Salafi tradition, distinguishes between God’s existential (kawni) will and legislative (shar`i) will. According to it, ethical valuation is restricted to the domain of what God legislates for His volitional creatures. Although these approaches differ in how they contextualize ethical behavior, both of them place ethical valuation strictly within the context of human volitional action. As a consequence, God’s actions in creation (and therefore what is observed in nature) can neither be taken as a pattern for determining ethical norms nor judged according to the ethical norms appropriate for human beings. The paper concludes that by making these distinctions, classical Islamic theology has the potential to effectively counter ethical objections to evolutionary theory.

scholarly journals Digital Evolution for Ecology Research: A Review

2021 ◽  
Vol 9 ◽  
Author(s):  
Emily Dolson ◽  
Charles Ofria
Keyword(s):  
Natural Selection ◽  
Evolutionary Theory ◽  
Scaling Laws ◽  
Evolutionary Dynamics ◽  
Ecological Communities ◽  
Ecological Research ◽  
Digital Evolution ◽  
Controlled System ◽  
Wide Range ◽  
Evolution Systems

In digital evolution, populations of computational organisms evolve via the same principles that govern natural selection in nature. These platforms have been used to great effect as a controlled system in which to conduct evolutionary experiments and develop novel evolutionary theory. In addition to their complex evolutionary dynamics, many digital evolution systems also produce rich ecological communities. As a result, digital evolution is also a powerful tool for research on eco-evolutionary dynamics. Here, we review the research to date in which digital evolution platforms have been used to address eco-evolutionary (and in some cases purely ecological) questions. This work has spanned a wide range of topics, including competition, facilitation, parasitism, predation, and macroecological scaling laws. We argue for the value of further ecological research in digital evolution systems and present some particularly promising directions for further research.

Writing and Evolutionary Theory

2019 ◽  
Author(s):  
Seán Hewitt
Keyword(s):  
Natural Selection ◽  
19Th Century ◽  
Evolutionary Theory ◽  
Charles Darwin ◽  
Cultural Anthropology ◽  
Natural Theology ◽  
Historical Study ◽  
Theory Of Evolution ◽  
Nature Study ◽  
The Impact

The development of evolutionary theory over the course of the 19th century was not confined to the theory of evolution by natural selection posited by Charles Darwin (b. 1809–d. 1882) and Alfred Russell Wallace (b. 1823–d. 1913). Encompassing the burgeoning science of geology, natural history, and biology and eventually being adapted into sociology, psychology, political theory, economics, and cultural anthropology, the theory of evolution quickly became both pervasive and divisive. Prior to Darwin’s intervention with the Origin of Species (1859), various theories of evolution were circulating, being accommodated within the field of natural theology or constituting a challenge to theories of intelligent design. Over the period, the interplay between literature and evolutionary theory was complex and pronounced: advances in science provoked new formal and thematic concerns for writers, and scientists used poetry and literary techniques to disseminate their arguments to wide readerships. During the period, the rise of natural historical study as a popular pursuit, and the Victorian emphasis on nature study as a moral, even religious, pursuit, meant that evolutionary ideas were adapted for various purposes and contested in both popular and specialist texts. Pre-Darwinian literature circulated evolutionary ideas mainly within the framework of natural theology (proving and discussing God’s existence through the study of Creation), but visions of harmony and beneficent design were challenged through the theory of natural selection, meaning that post-Darwinian literature more fully encompasses anthropological anxiety and the falling off of faith. Religious texts, and theological concerns, are thus central to the interplay between literature and science in the period. Toward the end of the century, the adaptation of Darwinism and evolutionary theory into various disciplines saw a proliferation of social Darwinism, branching off into eugenics, the impact of which would be felt most fully in the 20th century. This article focuses on writing and evolutionary theory in its immediate British and 19th-century contexts.

scholarly journals Who's afraid of epigenetics? Habits, instincts, and Charles Darwin’s evolutionary theory

2021 ◽  
Vol 43 (1) ◽  
Author(s):  
Mariagrazia Portera ◽  
Mauro Mandrioli
Keyword(s):  
Natural Selection ◽  
Evolutionary Theory ◽  
Crucial Role ◽  
Epigenetic Inheritance ◽  
Point Of View ◽  
Epigenetic Mechanisms ◽  
Intellectual Life ◽  
Entire Life ◽  
Theory Of Evolution ◽  
Expression Of Genes

AbstractOur paper aims at bringing to the fore the crucial role that habits play in Charles Darwin’s theory of evolution by means of natural selection. We have organized the paper in two steps: first, we analyse value and functions of the concept of habit in Darwin's early works, notably in his Notebooks, and compare these views to his mature understanding of the concept in the Origin of Species and later works; second, we discuss Darwin’s ideas on habits in the light of today’s theories of epigenetic inheritance, which describe the way in which the functioning and expression of genes is modified by the environment, and how these modifications are transmitted over generations. We argue that Darwin’s lasting and multifaceted interest in the notion of habit, throughout his intellectual life, is both conceptually and methodologically relevant. From a conceptual point of view, intriguing similarities can be found between Darwin’s (early) conception of habit and contemporary views on epigenetic inheritance. From a methodological point of view, we suggest that Darwin’s plastic approach to habits, from his early writings up to the mature works, can provide today’s evolutionary scientists with a viable methodological model to address the challenging task of extending and expanding evolutionary theory, with particular reference to the integration of epigenetic mechanisms into existing models of evolutionary change. Over his entire life Darwin has modified and reassessed his views on habits as many times as required by evidence: his work on this notion may represent the paradigm of a habit of good scientific research methodology.

Linguistic Selection: An Utterance-based Evolutionary Theory of Language Change

1996 ◽  
Vol 19 (2) ◽  
pp. 99-139 ◽  
Author(s):  
William Croft
Keyword(s):  
Natural Selection ◽  
Conceptual Change ◽  
Evolutionary Theory ◽  
Language Contact ◽  
Language Change ◽  
Biological Evolution ◽  
Selection Processes ◽  
Recent Developments ◽  
Theory Of Language ◽  
Evolutionary Taxonomy

Hull (1988) uses recent developments in the theory of biological evolution, in particular rigorous application of the population theory of species, a consistently phylogenetic approach to evolutionary taxonomy and a proposed resolution of the dispute over which levels natural selection operates, to propose a general analysis of selection processes which he then applies to conceptual change in science. Hull's model of selection is applied to language change. It is argued that the utterance plays the central role in linguistic selection, and causal mechanisms by which linguistic selection – language change – occurs are proposed. The final sections consider the possibility that selection occurs also at higher levels of linguistic organization, and suggest how language contact may be accounted for in terms of phylogenetic reticulation.

The expression of hybrid vigour in Drosophila subobscura

1955 ◽  
Vol 144 (915) ◽  
pp. 159-171 ◽  
Keyword(s):  
Natural Selection ◽  
Hybrid Vigour ◽  
Wild Populations ◽  
Balanced Polymorphism ◽  
Wide Range ◽  
In The Wild ◽  
High Level ◽  
Species Hybrids ◽  
Made In

By hybrid vigour we mean the possession by outbred organisms of a number of characters which would confer fitness in a wide range of environments. This definition deliberately includes both cases where heterozygous individuals are fitter in a Darwinian sense in the wild, and cases of species or other distant hybrids showing vigour in, for example, efficient utilization of food, long life, or high resistance to disease, although of low fitness because of infertility or for some other reason. Both types of phenomenon are well known, but whether it is convenient to consider them under the same heading will depend on the aspect of the problem being studied. For example, Dobzhansky (1950) preferred to divide hybrid vigour into ‘euheterosis’ as found in wild populations, and ‘luxuriance’ as exemplified in species hybrids. Such a distinction is a helpful one when the aspect studied is the role of natural selection in maintaining a balanced polymorphism in the wild. However, the high level of heterozygosity maintained by natural selection in many wild populations suggests that for many pairs of alleles the heterozygote is fitter than either homozygote. Where we have some knowledge of the mode of action of the different alleles present in a wild population at a given locus, as we have, for example, for the blood groups in man, it appears that different alleles produc qualitatively different substances. This has led to the suggestion that outbred organisms may be biochemically more versatile (Haldane 1948, 1954; Robertson & Reeve 1952). It is such versatility that all ‘hybrids’ may have in common, whether they result from outbreeding in the wild or from distant crosses made in the laboratory.

Sign in / Sign up

Export Citation Format

Share Document