Natural Selection as Agent of Evolutionary Change: A View from Paleoanthropology

2021 ◽  
pp. 419-439
Author(s):  
Ian Tattersall
Keyword(s):  
Natural Selection ◽  
Evolutionary Change

scholarly journals Evolution and evolvability: celebrating Darwin 200

2008 ◽  
Vol 5 (1) ◽  
pp. 44-46 ◽  
Author(s):  
John F.Y Brookfield
Keyword(s):  
Genetic Variation ◽  
Natural Selection ◽  
Time Scales ◽  
Evolutionary Change ◽  
Adaptive Mutation ◽  
Genetic Covariances ◽  
The Relationship ◽  
The Way

The concept of ‘evolvability’ is increasingly coming to dominate considerations of evolutionary change. There are, however, a number of different interpretations that have been put on the idea of evolvability, differing in the time scales over which the concept is applied. For some, evolvability characterizes the potential for future adaptive mutation and evolution. Others use evolvability to capture the nature of genetic variation as it exists in populations, particularly in terms of the genetic covariances between traits. In the latter use of the term, the applicability of the idea of evolvability as a measure of population's capacity to respond to natural selection rests on one, but not the only, view of the way in which we should envisage the process of natural selection. Perhaps the most potentially confusing aspects of the concept of evolvability are seen in the relationship between evolvability and robustness.

scholarly journals The genomics of adaptation

2012 ◽  
Vol 279 (1749) ◽  
pp. 5024-5028 ◽  
Author(s):  
Jacek Radwan ◽  
Wiesław Babik
Keyword(s):  
Genetic Variation ◽  
Natural Selection ◽  
Royal Society ◽  
Genetic Basis ◽  
Genomic Data ◽  
Evolutionary Change ◽  
Introductory Article ◽  
Technological Advances ◽  
A Genome ◽  
Genome Level

The amount and nature of genetic variation available to natural selection affect the rate, course and outcome of evolution. Consequently, the study of the genetic basis of adaptive evolutionary change has occupied biologists for decades, but progress has been hampered by the lack of resolution and the absence of a genome-level perspective. Technological advances in recent years should now allow us to answer many long-standing questions about the nature of adaptation. The data gathered so far are beginning to challenge some widespread views of the way in which natural selection operates at the genomic level. Papers in this Special Feature of Proceedings of the Royal Society B illustrate various aspects of the broad field of adaptation genomics. This introductory article sets up a context and, on the basis of a few selected examples, discusses how genomic data can advance our understanding of the process of adaptation.

Moving Targets

2012 ◽  
Author(s):  
Stephen J. Simpson ◽  
David Raubenheimer
Keyword(s):  
Life History ◽  
Natural Selection ◽  
Growth And Development ◽  
Early Growth ◽  
Evolutionary Change ◽  
Life History Strategies ◽  
Moving Targets ◽  
Gene Frequencies ◽  
Epigenetic Effects ◽  
As Species

This chapter studies intake and growth targets. For clarity, earlier chapters have treated intake and growth targets as static points integrated across a particular period in the life of an animal. In reality they are, of course, not static but rather trajectories that move in time. In the short term, the requirements of the animal change as environmental circumstances impose differing demands for nutrients and energy. At a somewhat longer timescale, targets move as the animal passes through the various stages of its life, from early growth and development to maturity, reproduction, and senescence. On an even longer timescale, nutritional traits are subject to natural selection and move as species evolve to exploit new or changing nutritional environments and to adopt differing life-history strategies. Presaging such evolutionary change in gene frequencies within populations are epigenetic effects, whereby the nutritional experiences of parents influence the behavior and metabolism of their offspring without requiring changes in gene frequencies.

Adaptable Ancestors

2020 ◽  
pp. 71-91
Author(s):  
David F. Bjorklund
Keyword(s):  
Natural Selection ◽  
Evolutionary Change ◽  
Behavioral Changes ◽  
Social Transmission ◽  
Significant Extent ◽  
Transmission Of Information ◽  
Selection Behavior ◽  
Novel Environments ◽  
High Level ◽  
Or Genes

The high level of plasticity shown by children today was also a feature of our forechildren. Experiences early in life can modify the morphology or behavior of an animal and result in new pressures that can be the focus of natural selection. Behavior, in fact, takes the lead in evolution, because it is more susceptible to change than morphology or genes. Most of the changes early in development, at least for mammals, were accomplished in the presence of mothers. To a significant extent, mothers are the environment for young mammals, making mothers the environment for evolutionary change. Significant behavioral changes in evolution are most likely to occur in large-brained animals, who are better able to deal with novel environments through innovation and social transmission of information than smaller-brained animals.

Darwinism

2014 ◽  
Author(s):  
Michael Ruse
Keyword(s):  
Natural Selection ◽  
Land Tenure ◽  
Charles Darwin ◽  
General Term ◽  
Evolutionary Change ◽  
Social Darwinism ◽  
Theory Of Evolution ◽  
Mendelian Genetics ◽  
Thomas Henry Huxley ◽  
Foundational Work

The modern usage of the term Darwinism dates from the publication of On the Origin of Species, by Charles Darwin, in which he argued for evolution through natural selection. Very soon after the appearance of the Origin (in 1859), Darwin’s great supporter Thomas Henry Huxley introduced the term Darwinism. The term—together with the related terms Darwinian and Darwinist—took root. The codiscoverer of natural selection, Alfred Russel Wallace, used the term as the title of a book expounding evolution: Darwinism: An Exposition of the Theory of Natural Selection, with Some of Its Applications. Note that there seems to be a fuzziness about the term. Some identify Darwinism with evolution through natural selection. Others suggest that the essence of Darwinism is not selection per se but change or variation. Late in the 19th century, George Romanes coined the term neo-Darwinism to cover those for whom natural selection is basically the only significant cause of change. In 1930 Ronald A. Fisher, in his Genetical Theory of Natural Selection, argued that the newly developed theory of Mendelian genetics offered the required foundation for a perspective that made natural selection the central force of evolutionary change. Although the British were happy to call the Darwin-Mendel synthesis neo-Darwinism, in America the synthesis was known as the synthetic theory of evolution. This reflects that in the New World it was Sewall Wright who did the foundational work in bringing Mendelian genetics into the evolutionary picture and that he never thought of natural selection as being the force that Fisher took it to be. For Wright and his followers, especially Theodosius Dobzhansky, genetic drift was always a major component of the evolutionary picture, and as Fisher pointed out nonstop, this is about as non-Darwinian a notion as it is possible to have. By 1959 professional evolutionists (on both sides of the Atlantic) agreed that Darwin had been right about natural selection: it is the major cause of evolutionary change. Neo-Darwinism fell into disuse, as everyone now used the term Darwinism for evolution through natural selection. Mention should also be made of so-called social Darwinism, the application of Darwinism to persons and groups within society. The earliest use apparently was during Darwin’s own lifetime, by a historian discussing land tenure in Ireland. However, it was not a popular or general term, coming into widespread use only in the 1940s, with the publication of the American historian Richard Hofstadter’s book Social Darwinism in American Thought.

Darwin's ““Imaginary Illustrations””: Creatively Teaching Evolutionary Concepts & the Nature of Science

2010 ◽  
Vol 72 (2) ◽  
pp. 82-89 ◽  
Author(s):  
Alan C. Love
Keyword(s):  
Natural Selection ◽  
Nature Of Science ◽  
Thought Experiments ◽  
Evolutionary Change ◽  
Evolutionary Concepts

An overlooked feature of Darwin's work is his use of ““imaginary illustrations”” to show that natural selection is competent to produce adaptive, evolutionary change. When set in the context of Darwin's methodology, these thought experiments provide a novel way to teach natural selection and the nature of science.

scholarly journals Plasticity-led evolution: evaluating the key prediction of frequency-dependent adaptation

2019 ◽  
Vol 286 (1897) ◽  
pp. 20182754 ◽  
Author(s):  
Nicholas A. Levis ◽  
David W. Pfennig
Keyword(s):  
Natural Selection ◽  
Phenotypic Plasticity ◽  
Adaptive Evolution ◽  
Natural Populations ◽  
Evolutionary Change ◽  
Adaptive Refinement ◽  
Fairy Shrimp ◽  
Extreme Form ◽  
Spadefoot Toad ◽  
Evolution By Natural Selection

Plasticity-led evolution occurs when a change in the environment triggers a change in phenotype via phenotypic plasticity, and this pre-existing plasticity is subsequently refined by selection into an adaptive phenotype. A critical, but largely untested prediction of plasticity-led evolution (and evolution by natural selection generally) is that the rate and magnitude of evolutionary change should be positively associated with a phenotype's frequency of expression in a population. Essentially, the more often a phenotype is expressed and exposed to selection, the greater its opportunity for adaptive refinement. We tested this prediction by competing against each other spadefoot toad tadpoles from different natural populations that vary in how frequently they express a novel, environmentally induced carnivore ecomorph. As expected, laboratory-reared tadpoles whose parents were derived from populations that express the carnivore ecomorph more frequently were superior competitors for the resource for which this ecomorph is specialized—fairy shrimp. These tadpoles were better at using this resource both because they were more efficient at capturing and consuming shrimp and because they produced more exaggerated carnivore traits. Moreover, they exhibited these more carnivore-like features even without experiencing the inducing cue, suggesting that this ecomorph has undergone an extreme form of plasticity-led evolution—genetic assimilation. Thus, our findings provide evidence that the frequency of trait expression drives the magnitude of adaptive refinement, thereby validating a key prediction of plasticity-led evolution specifically and adaptive evolution generally.

On the Legitimacy of the Darwinian Theory – August Weismann's First Creed

2013 ◽  
Vol 26 (1) ◽  
pp. 173-179
Author(s):  
Charlotte Weissman
Keyword(s):  
Natural Selection ◽  
Evolutionary Theory ◽  
Evolutionary Change ◽  
August Weismann ◽  
Darwinian Theory ◽  
Inaugural Lecture ◽  
Future Theory

ArgumentIn his inaugural lecture, “On the Legitimacy of the Darwinian Theory,” August Weismann followed closely in Darwin's footsteps, but provided at the same time an outline of the essentials of his future theory of heredity, development, variation, and speciation. This was Weismann's first support of the evolutionary theory, and it shows his commitment to natural selection as the mechanism of evolution. For Weismann, “Darwin's Theory” meant natural selection. Natural selection, and more generally selectionism, became Weismann's major explanatory principle for evolutionary change and the most important element driving his thought.

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