The scientific theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the mid-19th century and was set out in detail in Darwin's book "On the Origin of Species". Evolution by natural selection was first demonstrated by the observation that more offspring are often produced than can possibly survive. This is followed by three observable facts about living organisms: (1) traits vary among individuals with respect to their morphology, physiology and behaviour (phenotypic variation), (2) different traits confer different rates of survival and reproduction (differential fitness) and (3) traits can be passed from generation to generation (heritability of fitness).
Introduction
Evolution
Evolution | Introduction
Charles Darwin and Alfred Russel Wallace Charles Darwin and Alfred Russel Wallace Anaximander and Empedocles. The proposal that one type of organism could descend from another type goes back to some of the first pre-Socratic Greek philosophers, such as Anaximander and Empedocles.
which of the following is the ultimate result of evolution
user
Sorry. I cannot find the answer based on the context.
assistant
what is evolution?
user
It is change in the heritable characteristics of biological populations over successive generations.
assistant
who was the first to study this?
user
Evolution is change in heritable traits of biological organisms over successive generations, due to natural selection and other mechanisms. Evolution, or Theory of Evolution, also may refer to:
Evolution (disambiguation) | Introduction
Evolution is the process of change in all forms of life over generations, and evolutionary biology is the study of how evolution occurs. Biological populations evolve through genetic changes that correspond to changes in the organisms' observable traits. Genetic changes include mutations, which are caused by damage or replication errors in organisms' DNA. As the genetic variation of a population drifts randomly over generations, natural selection gradually leads traits to become more or less common based on the relative reproductive success of organisms with those traits. The age of the Earth is about 4.5 billion years. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago.
Introduction to evolution | Introduction
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction. Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources of genetic variation. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or rare within a population. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms and molecules.
Evolution | Introduction
The following outline is provided as an overview of and topical guide to evolution: Evolution – change in heritable traits of biological organisms over generations due to natural selection, mutation, gene flow, and genetic drift. Also known as descent with modification. Over time these evolutionary processes lead to formation of new species (speciation), changes within lineages (anagenesis), and loss of species (extinction). "Evolution" is also another name for evolutionary biology, the subfield of biology concerned with studying evolutionary processes that produced the diversity of life on Earth.
Outline of evolution | Introduction
This section contains a list of works on evolution, the change across successive generations in the heritable characteristics of biological populations.
Bibliography of biology | Evolutionary biology
The implication from such a find is that modern reptiles and birds arose from a common ancestor.
Introduction to evolution | Fossil record
The scientific theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the mid-19th century and was set out in detail in Darwin's book "On the Origin of Species". Evolution by natural selection was first demonstrated by the observation that more offspring are often produced than can possibly survive. This is followed by three observable facts about living organisms: (1) traits vary among individuals with respect to their morphology, physiology and behaviour (phenotypic variation), (2) different traits confer different rates of survival and reproduction (differential fitness) and (3) traits can be passed from generation to generation (heritability of fitness).
Evolution | Introduction
Darwin's theory of natural selection laid the groundwork for modern evolutionary theory, and his experiments and observations showed that the organisms in populations varied from each other, that some of these variations were inherited, and that these differences could be acted on by natural selection. However, he could not explain the source of these variations. Like many of his predecessors, Darwin mistakenly thought that heritable traits were a product of use and disuse, and that features acquired during an organism's lifetime could be passed on to its offspring. He looked for examples, such as large ground feeding birds getting stronger legs through exercise, and weaker wings from not flying until, like the ostrich, they could not fly at all.
Introduction to evolution | Source of variation
Three British men, all medically qualified and publishing between 1813 and 1819, William Lawrence, William Charles Wells and Prichard, addressed issues relevant to human evolution. All tackled the question of variation and race in humans; all agreed that these differences were heritable, but only Wells approached the idea of natural selection as a cause. Science historian Conway Zirkle has described Prichard as an evolutionary thinker who came very close "to explaining the origin of new forms through the operation of natural selection although he never actually stated the proposition in so many words." Prichard indicated Africa (indirectly) as the place of human origin, in this summary passage:
James Cowles Prichard | Evolution
Natural selection, introduced in 1859 as the central mechanism of evolution by Charles Darwin, is the differential survival and reproduction of individuals due to differences in phenotype. The mechanism directly implies evolution, a change in heritable traits of a population over time.
Teleology in biology | Natural selection
Darwin gained extensive experience as he collected and studied the natural history of life forms from distant places. Through his studies, he formulated the idea that each species had developed from ancestors with similar features. In 1838, he described how a process he called natural selection would make this happen. The size of a population depends on how much and how many resources are able to support it. For the population to remain the same size year after year, there must be an equilibrium, or balance between the population size and available resources. Since organisms produce more offspring than their environment can support, not all individuals can survive out of each generation.
Introduction to evolution | Natural selection
Naturalists began to focus on the variability of species; the emergence of paleontology with the concept of extinction further undermined static views of nature. In the early 19th century Jean-Baptiste Lamarck (1744–1829) proposed his theory of the transmutation of species, the first fully formed theory of evolution. In 1858 Charles Darwin and Alfred Russel Wallace published a new evolutionary theory, explained in detail in Darwin's "On the Origin of Species" (1859). Unlike Lamarck, Darwin proposed common descent and a branching tree of life, meaning that two very different species could share a common ancestor. Darwin based his theory on the idea of natural selection: it synthesized a broad range of evidence from animal husbandry, biogeography, geology, morphology, and embryology.
History of evolutionary thought | Introduction
Leticia Avilés is an evolutionary biologist and ecologist who studies the evolution of social behavior and the evolution of life history traits in metapopulations. Her methods include a combination of theory and empirical work, the latter using social spiders as a model system. Her research on these organisms has addressed questions such as why some spiders live in groups, why do they exhibit highly female-biased sex ratios, and why have they evolved a system where individuals remain in the natal nest to mate from generation to generation.
Leticia Avilés | Introduction
Thus, in successive generations members of a population are more likely to be replaced by the progenies of parents with favourable characteristics that have enabled them to survive and reproduce in their respective environments. In the early 20th century, other competing ideas of evolution such as mutationism and orthogenesis were refuted as the modern synthesis reconciled Darwinian evolution with classical genetics, which established adaptive evolution as being caused by natural selection acting on Mendelian genetic variation. All life on Earth shares a last universal common ancestor (LUCA) that lived approximately 3.5–3.8 billion years ago. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, to fossilised multicellular organisms.
Evolution | Introduction
That prompted him to branch out into anthropology and evolutionary biology.
Gary R. Johnson | Introduction
We are not going to find the answers in human evolution until we have framed the right questions, and the questions are difficult because they involve both body and mind, physique and culture—tools and symbols as well as cerebral configurations. Author Orville Prescott wrote,
Loren Eiseley | 1950s
Evolution does not attempt to explain the origin of life (covered instead by abiogenesis), but it does explain how early lifeforms evolved into the complex ecosystem that we see today. Based on the similarities between all present-day organisms, all life on Earth is assumed to have originated through common descent from a last universal ancestor from which all known species have diverged through the process of evolution. All individuals have hereditary material in the form of genes received from their parents, which they pass on to any offspring. Among offspring there are variations of genes due to the introduction of new genes via random changes called mutations or via reshuffling of existing genes during sexual reproduction.
Introduction to evolution | Introduction
These communities used to be quite widespread up to the nineteenth century. They did not have any written language and Reed notes that within a very few years following contact with Europeans their social structure often changed substantially (p162). So she relies on the earliest anthropological records, drawing particularly on a review of such work by Robert Briffault published in 1927 (page xv).
Woman's Evolution | Introduction
Although Hooker professed not to have changed his views on Darwin's theory of evolution by natural selection, the book contains an introductory essay on biogeography written from a Darwinian point of view, making the book the first case study for the theory.
Flora Tasmaniae | Introduction
Human evolution is the biological process that led to the emergence of the species "Homo sapiens(binomial nomenclature for the human species)": "Human evolution" may also refer to:
Human evolution (disambiguation) | Introduction
Edelman and Gally were the first to point out the pervasiveness of degeneracy in biological systems and the fundamental role that degeneracy plays in facilitating evolution.
Gerald Edelman | Evolution theory
In the third edition of his "On the Origin of Species" published in 1861, Charles Darwin added a "Historical Sketch" giving due credit to naturalists who had preceded him in publishing the opinion that species undergo modification, and that the existing forms of life have descended by true generation from pre-existing forms. According to Darwin: Evolutionary biologist Ernst Mayr has written that Buch was the first naturalist to suggest geographic speciation, in 1825.
Christian Leopold von Buch | Evolution
Human evolution is the evolutionary process that led to the emergence of anatomically modern humans, beginning with the evolutionary history of primates—in particular genus "Homo"—and leading to the emergence of "Homo sapiens" as a distinct species of the hominid family, which includes the great apes. This process involved the gradual development of traits such as human bipedalism and language, as well as interbreeding with other hominins, which indicate that human evolution was not linear but a web. The study of human evolution involves several scientific disciplines, including physical anthropology, primatology, archaeology, paleontology, neurobiology, ethology, linguistics, evolutionary psychology, embryology and genetics.
Human evolution | Introduction
T. Patterson as his Vice-presidents and Ernst Mayr as secretary. This society grew as an extension of the US National Research Council's Committee on Common Problems of Genetics and Paleontology (later renamed the Committee on Common Problems of Genetics, Paleontology and Systematics). The first annual meeting of the society was held in Boston, December 28–31, 1946. A grant from the American Philosophical Society led to the publication of the journal "Evolution".
Society for the Study of Evolution | Introduction
In opposition to what he sees as the conventional wisdom that civilization has been a static environment which imposed stabilizing selection on humans, Cochran, along with like-minded anthropologists such as John D. Hawks, contends that haplotype and other data indicate the selection of genes has been strongest since the advent of farming and civilization.
Gregory Cochran | Human evolution
Kelley described this as a natural evolution:
David E. Kelley | Writing
Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis) and loss of species (extinction) throughout the evolutionary history of life on Earth. Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct phylogenetic trees.
Evolution | Introduction
Rebecca M. Kilner FRES is a British evolutionary biologist, and a professor of evolutionary biology at the University of Cambridge.
Rebecca Kilner | Introduction
William Bateson in 1884 distinguished between the origin of novel variations and the action of natural selection ("Materials for the Study of Variation Treated with Especial Regard to Discontinuity in the Origin of Species").
Emergent evolution | Response to Darwin's "Origin of Species"
J. B. S. Haldane – W. D. Hamilton – Hardy–Weinberg principle – heredity – hierarchy of life – history of evolutionary thought – history of speciation – homologous chromosomes – homology (biology) – horizontal gene transfer – human evolution – human evolutionary genetics – human vestigiality – Julian Huxley – Thomas Henry Huxley
Index of evolutionary biology articles | H
Carina Maria Schlebusch is an evolutionary biologist at the University of Uppsala in Sweden. She is a specialist in the population history of Africa. In 2017 she was the co-author of a paper that suggested that modern humans emerged more than 300,000 years ago.
Carina M. Schlebusch | Introduction
In 1872, Gulick was the first to propose the theory that the majority of evolutionary changes are the result of chance variation, which has no effect on the survival and reproductive success of a species (today called "genetic drift"). He came to this theory while noting that there was a large diversity of local populations of Hawaiian land snails (Achatinella) which showed random variation under seemingly identical environmental conditions. Although he certainly promoted the importance of random factors in evolution, he also was a strong supporter of Darwinian natural selection, and this led to disagreement with Moritz Wagner's "Migration Theory" of the origin of species.
J. T. Gulick | Evolutionary theories
The biological classification introduced by Carl Linnaeus in 1735 explicitly recognised the hierarchical nature of species relationships, but still viewed species as fixed according to a divine plan. Other naturalists of this time speculated on the evolutionary change of species over time according to natural laws. In 1751, Pierre Louis Maupertuis wrote of natural modifications occurring during reproduction and accumulating over many generations to produce new species. Georges-Louis Leclerc, Comte de Buffon suggested that species could degenerate into different organisms, and Erasmus Darwin proposed that all warm-blooded animals could have descended from a single microorganism (or "filament"). The first full-fledged evolutionary scheme was Jean-Baptiste Lamarck's "transmutation" theory of 1809, which envisaged spontaneous generation continually producing simple forms of life that developed greater complexity in parallel lineages with an inherent progressive tendency, and postulated that on a local level, these lineages adapted to the environment by inheriting changes caused by their use or disuse in parents.
Evolution | Pre-Darwinian
Evolution in Mendelian Populations is a lengthy 1931 scientific paper on evolution by the American population geneticist Sewall Wright. The paper was first published in "Genetics" volume 16, pages 97–159. In it, Wright outlines various concepts, including genetic drift, effective population size, and inbreeding. A contemporary review by R.A. Fisher can be found here
Evolution in Mendelian Populations | Introduction
Introducing Evolution is a 2001 graphic study guide to Evolution written by Dylan Evans and illustrated by Howard Selina. The volume, according to the publisher's website, "provides a step-by-step guide to ‘Darwin’s dangerous idea’ and takes a fresh look at the often misunderstood concepts of natural selection and the selfish gene."
Introducing Evolution | Introduction
This is due to Biruni describing the idea of artificial selection and then applying it to nature: In the 13th century, Nasir al-Din al-Tusi explains how the elements evolved into minerals, then plants, then animals, and then humans. Tusi then goes on to explain how hereditary variability was an important factor for biological evolution of living things:
Early Islamic philosophy | Evolution
Every variety is a deviation which becomes a species as soon as it is permanent by reproduction. Deviations in essential organs may thus gradually become new genera.
Constantine Samuel Rafinesque | Evolution
There must be a competitive struggle for resources that aid in survival. As a result, Darwin realised that it was not chance alone that determined survival. Instead, survival of an organism depends on the differences of each individual organism, or "traits," that aid or hinder survival and reproduction. Well-adapted individuals are likely to leave more offspring than their less well-adapted competitors. Traits that hinder survival and reproduction would "disappear" over generations. Traits that help an organism survive and reproduce would "accumulate" over generations. Darwin realised that the unequal ability of individuals to survive and reproduce could cause gradual changes in the population and used the term "natural selection" to describe this process.
Introduction to evolution | Natural selection
This misunderstanding was called the inheritance of acquired characters and was part of the theory of transmutation of species put forward in 1809 by Jean-Baptiste Lamarck. In the late 19th century this theory became known as Lamarckism. Darwin produced an unsuccessful theory he called pangenesis to try to explain how acquired characteristics could be inherited. In the 1880s August Weismann's experiments indicated that changes from use and disuse could not be inherited, and Lamarckism gradually fell from favour. The missing information needed to help explain how new features could pass from a parent to its offspring was provided by the pioneering genetics work of Gregor Mendel.
Introduction to evolution | Source of variation
Professor of biology Jerry Coyne sums up biological evolution succinctly: This shows the breadth and scope of the issue, incorporating the scientific fields of zoology, botany, genetics, geology, and paleontology, among many others. But the central core of evolution is generally defined as changes in trait or gene frequency in a population of organisms from one generation to the next. This has been dubbed the standard genetic definition of evolution. Natural selection is only one of several mechanisms in the theory of evolutionary change that explains how organisms historically adapt to changing environments. The principles of heredity were re-discovered in 1900, after Darwin's death, in Gregor Mendel's research on the inheritance of simple trait variations in peas.
Evolution as fact and theory | Evolution
(Alfred Russel Wallace is recognized as the co-discoverer of this concept as he helped research and experiment with the concept of evolution.) Evolution is now used to explain the great variations of life found on Earth. Darwin theorized that species flourish or die when subjected to the processes of natural selection or selective breeding. Genetic drift was embraced as an additional mechanism of evolutionary development in the modern synthesis of the theory.
Biology | Evolution
From the strong principle of inheritance, any selected variety will tend to propagate its new and modified form. Starting with the third edition, Darwin prefaced the introduction with a sketch of the historical development of evolutionary ideas. In that sketch he acknowledged that Patrick Matthew had, unknown to Wallace or himself, anticipated the concept of natural selection in an appendix to a book published in 1831; in the fourth edition he mentioned that William Charles Wells had done so as early as 1813.
On the Origin of Species | Title pages and introduction
According to Richards, "The Races of Men" advocated "a common material origin of life and its evolution by a process of saltatory descent"; that is to say, new species arose not by gradual change but by sudden leaps due to shifts in embryonic development. Knox tentatively concluded that "simple animals ... may have produced by continuous generation the more complex animals of after ages . . . the fish of the early world may have produced reptiles, then again birds and quadrupeds; lastly, man himself?" Newly formed species survived or perished according to external conditions, which acted as "potent checks to an infinite variety of forms".
Robert Knox | Evolution
A central organizing concept in biology is that life changes and develops through evolution, and that all life-forms known have a common origin. The theory of evolution postulates that all organisms on the Earth, both living and extinct, have descended from a common ancestor or an ancestral gene pool. This universal common ancestor of all organisms is believed to have appeared about 3.5 billion years ago. Biologists regard the ubiquity of the genetic code as definitive evidence in favor of the theory of universal common descent for all bacteria, archaea, and eukaryotes (see: origin of life). The term "evolution" was introduced into the scientific lexicon by Jean-Baptiste de Lamarck in 1809, and fifty years later Charles Darwin posited a scientific model of natural selection as evolution's driving force.
Biology | Evolution
"E. coli" long-term evolution experiment - ecological genetics – ecological selection – "Endless Forms Most Beautiful" – endosymbiosis – error threshold (evolution) – evidence of common descent – evolution – evolutionary arms race – evolutionary capacitance "Evolution:" of ageing – of the brain – of cetaceans – of complexity – of dinosaurs – of the eye – of fish – of the horse – of insects – of human intelligence – of mammalian auditory ossicles – of mammals – of monogamy – of sex – of sirenians – of tetrapods – of the wolf evolutionary developmental biology – evolutionary dynamics – evolutionary game theory - evolutionary history of life – evolutionary history of plants – evolutionary medicine - evolutionary neuroscience – evolutionary psychology – evolutionary radiation – evolutionarily stable strategy – evolutionary taxonomy - evolutionary tree – evolvability – experimental evolution – exaptation – extinction
Index of evolutionary biology articles | E
produce a race of well scented hounds, instead of those who catch their prey by swiftness". The same "principle of variation" would influence "every species of plant, whether growing in a forest or a meadow". He came to his ideas as the result of experiments in plant and animal breeding, some of which he outlined in an unpublished manuscript, the "Elements of Agriculture". He distinguished between heritable variation as the result of breeding, and non-heritable variations caused by environmental differences such as soil and climate. Though he saw his "principle of variation" as explaining the development of varieties, Hutton rejected the idea that evolution might originate species as a "romantic fantasy", according to palaeoclimatologist Paul Pearson.
James Hutton | Evolution
It was thought that human embryos passed through an amphibian then a reptilian stage before completing their development as mammals. Such a re-enactment, often called "recapitulation theory", is not supported by scientific evidence. What does occur, however, is that the first stages of development are similar in broad groups of organisms. At very early stages, for instance, all vertebrates appear extremely similar, but do not exactly resemble any ancestral species. As development continues, specific features emerge from this basic pattern.
Introduction to evolution | Embryology
Human evolution is the study of the biological evolution of humans as a distinct species from its common ancestors with other animals. Analysis of fossil evidence and genetic distance are two of the means by which scientists understand this evolutionary history. Fossil evidence suggests that humans' earliest hominid ancestors may have split from other primates as early as the late Oligocene, circa 26 to 24 Ma, and that by the early Miocene, the adaptive radiation of many different hominoid forms was well underway. Evidence from the molecular dating of genetic differences indicates that the gibbon lineage (family Hylobatidae) diverged between 18 and 12 Ma, and the orangutan lineage (subfamily Ponginae) diverged about 12 Ma.
Rejection of evolution by religious groups | Human evolution
Other hosts were added by the same process until the modern bewildering diversity of life cycle patterns developed.
Digenea | Evolution
Scientific evidence for evolution comes from many aspects of biology and includes fossils, homologous structures, and molecular similarities between species' DNA.
Introduction to evolution | Evidence for evolution
Distinctive human genetic variability has arisen as the result of the founder effect, by archaic admixture and by recent evolutionary pressures.
Human evolution | "H. sapiens"
Olivia P. Judson (born 1970) is an evolutionary biologist and science writer.
Olivia Judson | Introduction
Darwin and his contemporaries viewed evolution as a slow and gradual process. Evolutionary trees are based on the idea that profound differences in species are the result of many small changes that accumulate over long periods. Gradualism had its basis in the works of the geologists James Hutton and Charles Lyell. Hutton's view suggests that profound geological change was the cumulative product of a relatively slow continuing operation of processes which can still be seen in operation today, as opposed to catastrophism which promoted the idea that sudden changes had causes which can no longer be seen at work. A uniformitarian perspective was adopted for biological changes.
Introduction to evolution | Rate of change
Shultz urged broad comparative studies to identify uniquely human traits.
Human evolutionary developmental biology | Introduction
Mayr, on the basis of an understanding of genes and direct observations of evolutionary processes from field research, introduced the biological species concept, which defined a species as a group of interbreeding or potentially interbreeding populations that are reproductively isolated from all other populations. Both Dobzhansky and Mayr emphasised the importance of subspecies reproductively isolated by geographical barriers in the emergence of new species. The palaeontologist George Gaylord Simpson helped to incorporate palaeontology with a statistical analysis of the fossil record that showed a pattern consistent with the branching and non-directional pathway of evolution of organisms predicted by the modern synthesis.
Introduction to evolution | Modern synthesis
D. Hamilton, Alexey Kondrashov, George C. Williams, Harris Bernstein, Carol Bernstein, Michael M. Cox, Frederic A. Hopf and Richard E. Michod – have suggested competing explanations for how a vast array of different living species maintain sexual reproduction.
Evolution of sexual reproduction | Historical perspective
Cambrian explosion – camouflage – Sean B. Carroll – catagenesis – gene-centered view of evolution – cephalization – Sergei Chetverikov – chronobiology – chronospecies – clade – cladistics – climatic adaptation – coalescent theory – co-evolution – co-operation – coefficient of relationship – common descent – convergent evolution – creation–evolution controversy – cultivar – conspecific song preference
Index of evolutionary biology articles | C
Human evolution from its first separation from the last common ancestor of humans and chimpanzees is characterized by a number of morphological, developmental, physiological, and behavioral changes. The most significant of these adaptations are bipedalism, increased brain size, lengthened ontogeny (gestation and infancy), and decreased sexual dimorphism. The relationship between these changes is the subject of ongoing debate. Other significant morphological changes included the evolution of a power and precision grip, a change first occurring in "H. erectus".
Human evolution | Anatomical changes
These points convinced Darwin that transmutation of species must be occurring, and in his "Red Notebook" he jotted down his first evolutionary ideas. He began specific transmutation notebooks with speculations on variation in offspring "to adapt & alter the race to "changing" world", and sketched an "irregularly branched" genealogical branching of a single evolutionary tree. Animal observations of an orangutan at the zoo showed how human its expressions looked, confirming his thoughts from the "Beagle" voyage that there was little gulf between man and animals. He investigated animal breeding and found parallels to nature removing runts and keeping the fit, with farmers deliberately selecting breeding animals so that through "a thousand intermediate forms" their descendants were significantly changed.
Inception of Darwin's theory | Introduction
Such a view can seem to contradict the fossil record, which often shows evidence of new species appearing suddenly, then persisting in that form for long periods. In the 1970s palaeontologists Niles Eldredge and Stephen Jay Gould developed a theoretical model that suggests that evolution, although a slow process in human terms, undergoes periods of relatively rapid change (ranging between 50,000 and 100,000 years) alternating with long periods of relative stability. Their theory is called "punctuated equilibrium" and explains the fossil record without contradicting Darwin's ideas.
Introduction to evolution | Rate of change
Georges Cuvier, Jean Baptiste Bory de Saint-Vincent, Louis Antoine Desmoulins and Virey all struggled to determine the origin and age of man.
Julien-Joseph Virey | Evolution
This timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. In biology, evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organization, from kingdoms to species, and individual organisms and molecules, such as DNA and proteins. The similarities between all present day organisms indicate the presence of a common ancestor from which all known species, living and extinct, have diverged through the process of evolution. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct.
Timeline of the evolutionary history of life | Introduction
Laurence Daniel Hurst (born 6 January 1965) is a Professor of Evolutionary Genetics in the Department of Biology and Biochemistry at the University of Bath and the director of the Milner Centre for Evolution.
Laurence Hurst | Introduction
Galápagos Islands – gene – gene-centric view of evolution – gene duplication – gene flow – gene pool – genetic drift – genetic hitchhiking – genetic recombination – genetic variation – genotype – genotype-environment correlation – genotype-environment interaction – genotype-phenotype distinction – Stephen Jay Gould – gradualism – Peter and Rosemary Grant – group selection
Index of evolutionary biology articles | G
Biogeography is the study of the geographical distribution of species. Evidence from biogeography, especially from the biogeography of oceanic islands, played a key role in convincing both Darwin and Alfred Russel Wallace that species evolved with a branching pattern of common descent. Islands often contain endemic species, species not found anywhere else, but those species are often related to species found on the nearest continent. Furthermore, islands often contain clusters of closely related species that have very different ecological niches, that is have different ways of making a living in the environment. Such clusters form through a process of adaptive radiation where a single ancestral species colonises an island that has a variety of open ecological niches and then diversifies by evolving into different species adapted to fill those empty niches.
Introduction to evolution | Biogeography
This study, published in the Proceedings of the National Academy of Sciences in 2008, has been presented as evidence for evolution in modern times.
Duncan Irschick | Research
The evidence for speciation in this case was morphology (physical appearance) and lack of natural interbreeding. These fish have complex mating rituals and a variety of colorations; the slight modifications introduced in the new species have changed the mate selection process and the five forms that arose could not be convinced to interbreed.
Introduction to evolution | Speciation
The Causes of Evolution is a 1932 book on evolution by J.B.S. Haldane (1990 edition ), based on a series of January 1931 lectures entitled "A Re-examination of Darwinism". It was influential in the founding of population genetics and the modern synthesis.
The Causes of Evolution | Introduction
By the 1850s, whether or not species evolved was a subject of intense debate, with prominent scientists arguing both sides of the issue. The publication of Charles Darwin's "On the Origin of Species" fundamentally transformed the discussion over biological origins. Darwin argued that his branching version of evolution explained a wealth of facts in biogeography, anatomy, embryology, and other fields of biology. He also provided the first cogent mechanism by which evolutionary change could persist: his theory of natural selection. One of the first and most important naturalists to be convinced by "Origin" of the reality of evolution was the British anatomist Thomas Henry Huxley.
History of evolutionary thought | 1859–1930s: Darwin and his legacy
"The earliest "H. sapiens" remains differ significantly from australopithecines in both size and anatomical details," he notes, "Insofar as we can tell, these changes were sudden and not gradual."
Milford H. Wolpoff | Multiregional evolution and the punctuated equilibrium theory
Aoife McLysaght is a Professor in the Molecular Evolution Laboratory of the Smurfit Institute of Genetics, University of Dublin in Ireland.
Aoife McLysaght | Introduction
Subsequent work into genetics, mutation, paleontology, and developmental biology expanded the applicability and scope of Darwin's original theory.
Evolution as fact and theory | Evolution
In general, morphological changes are too rapid to determine from which cotemporal species a new species originated, as seen in the evolution of modern humans.
Rate of evolution | Fossil record
Here we return to the population level. Over many generations, the success of the species' behaviour in its ancestral environment—or more technically, the environment of evolutionary adaptedness (EEA) may result in evolution as measured by a change in its genes.
Tinbergen's four questions | Causal relationships
RNA folding was also introduced to allow for a non-linear genotype to phenotype mapping to study evolution on complex fitness landscapes . The first phase-phase trajectory of a chaotic attractor in an ecological food-chain model of three differential equations appeared long before chaos became popular. She pioneered the use of cellular automata for studying spatial ecological and evolutionary processes and demonstrated that spatial pattern formation can revert evolutionary selection pressures.
Paulien Hogeweg | Research
The combination of mutations creating new alleles at random, and natural selection picking out those that are useful, causes an adaptation. This is when organisms change in ways that help them to survive and reproduce. Many such changes, studied in evolutionary developmental biology, affect the way the embryo develops into an adult body.
Introduction to genetics | Genes and evolution
The offspring differs from the parent in minor random ways. If those differences are helpful, the offspring is more likely to survive and reproduce. This means that more offspring in the next generation will have that helpful difference and individuals will not have equal chances of reproductive success. In this way, traits that result in organisms being better adapted to their living conditions become more common in descendant populations. These differences accumulate resulting in changes within the population. This process is responsible for the many diverse life forms in the world.
Introduction to evolution | Introduction
Dawkins declares that there was no first person, to make the point that evolutionary biologists use the term "species" to demark differences in gene composition — over often thousands of generations of separation — rather than from any one generation to the next. To illustrate this he undertakes a thought-experiment involving family photographs. If, hypothetically, there existed a complete set of photographs of all one's direct male ancestors arranged in order of birth date (or hatch date) from youngest to oldest stretching back millions of generations, from one generation to the next one would not perceive much difference between any two adjacent pictures—looking at a picture of one's grandfather or great-grandfather one is looking at a picture of a human—but if one looked at a picture from 185 million generations back one would see an image of some kind of fish-like animal.
The Magic of Reality | Synopsis
Some questions biologists have attempted to answer include: Why do some organisms have gamete dimorphism?
Evolution of sexual reproduction | Questions
A difficulty with the metabolism-first scenario is finding a way for organisms to evolve. Without the ability to replicate as individuals, aggregates of molecules would have "compositional genomes" (counts of molecular species in the aggregate) as the target of natural selection. However, a recent model shows that such a system is unable to evolve in response to natural selection.
History of Earth | Metabolism first: iron–sulfur world
On the Origin of Species (or, more completely, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life), published on 24 November 1859, is a work of scientific literature by Charles Darwin which is considered to be the foundation of evolutionary biology. Darwin's book introduced the scientific theory that populations evolve over the course of generations through a process of natural selection. The book presented a body of evidence that the diversity of life arose by common descent through a branching pattern of evolution. Darwin included evidence that he had collected on the "Beagle" expedition in the 1830s and his subsequent findings from research, correspondence, and experimentation.
On the Origin of Species | Introduction
Wilson was one of the first to have used the term "evolution" in the context of biological speciation. In 1830, he used this term in a paper on the history of goat and sheep, he wrote: Wilson's use of the term predated Charles Lyell in 1832. Wilson had rejected the evolution of species for creationism.
James Wilson (zoologist) | Evolution
Susumu Ohno – Aleksandr Oparin – "On The Origin of Species" – Ordovician radiation – origin of birds – origin of language – orthologous genes
Index of evolutionary biology articles | O
The biogeographical patterns Charles Darwin observed in places such as the Galápagos Islands during the second voyage of HMS "Beagle" caused him to doubt the fixity of species, and in 1837 Darwin started the first of a series of secret notebooks on transmutation. Darwin's observations led him to view transmutation as a process of divergence and branching, rather than the ladder-like progression envisioned by Jean-Baptiste Lamarck and others. In 1838 he read the new 6th edition of "An Essay on the Principle of Population", written in the late 18th century by Thomas Robert Malthus. Malthus' idea of population growth leading to a struggle for survival combined with Darwin's knowledge on how breeders selected traits, led to the inception of Darwin's theory of natural selection.
History of evolutionary thought | Natural selection
In January, 2007, Joseph L. Graves, Jr. answered visitors questions about evolutionary biology
Joseph L. Graves Jr. | References
race (biology) – Red Queen hypothesis – recapitulation theory – recent African origin of modern humans – recombination – Bernhard Rensch – reinforcement (speciation) – Reproductive coevolution in "Ficus" – "r/K" selection theory
Index of evolutionary biology articles | R
Before its use to describe biological evolution, the term "evolution" was originally used to refer to any orderly sequence of events with the outcome somehow contained at the start. The first five editions of Darwin's in "Origin of Species" used the word "evolved", but the word "evolution" was only used in its sixth edition in 1872. By then, Herbert Spencer had developed the concept theory that organisms strive to evolve due to an internal "driving force" (orthogenesis) in 1862. Edward B. Tylor and Lewis H Morgan brought the term "evolution" to anthropology though they tended toward the older pre-Spencerian definition helping to form the concept of unilineal (social) evolution used during the later part of what Trigger calls the Antiquarianism-Imperial Synthesis period (c1770-c1900).
Evolutionism | 19th-century teleological use
Therefore, comparisons can be made for the exact molecular changes in evolved strains during adaptation to novel conditions.
Bacteriophage experimental evolution | Introduction
Aiello studies evolutionary anthropology with focuses on human adaptation and life history, as well as the evolution of the brain, diet, language and cognition, and locomotion and its energetic costs. She has also researched Paleolithic hominids and their thermoregulation and climate adaptation. In collaboration with Peter Wheeler she developed the Expensive Tissue Hypothesis, regarding early humans, according to which there is an inverse correlation between the increase in brain size during human evolution and the parallel reduction of the digestive tract as a result of richer protein animal foods. Another idea she posited, was that higher reproductive costs would be the effect of this increase in brain size, which was compensated by the females increasing in size faster than the males.
Leslie C. Aiello | Research areas
John Hawks is an associate professor of anthropology at the University of Wisconsin–Madison. He also maintains a paleoanthropology blog. Contrary to the common view that cultural evolution has made human biological evolution insignificant, Hawks believes that biological evolution has sped up in recent history.
John D. Hawks | Introduction
She believes that a good understanding of genetic drift and random chance could prevent misunderstandings surrounding evolution. Her current research goal focuses on complexity in life-histories and symbiosis between hosts and microbes, including the microbiota of insects.
Nancy A. Moran | Introduction
Based on archaeological and paleontological evidence, it has been possible to infer, to some extent, the ancient dietary practices of various "Homo" species and to study the role of diet in physical and behavioral evolution within "Homo".
Human evolution | Evolution of genus "Homo"
Owen's approach to evolution can be seen as having anticipated the issues that have gained greater attention with the recent emergence of evolutionary developmental biology. Owen was the first president of the Microscopical Society of London in 1839 and edited many issues of its journal – then known as "The Microscopic Journal".
Richard Owen | Introduction
(This was written in a reference to Charles Lyell's ideas of "centres of creation".) Darwin notes the gradations in size of the beaks of species of finches, suspects that species "are confined to different islands", "But there is not space in this work, to enter into this curious subject." Later editions hint at his new ideas on evolution: Considering the small size of these islands, we feel the more astonished at the number of their aboriginal beings, and at their confined range... within a period geologically recent the unbroken ocean was here spread out. Hence, both in space and time, we seem to be brought somewhat near to that great fact – that mystery of mysteries – the first appearance of new beings on this earth.
The Voyage of the Beagle | Second edition: changing ideas on evolution
Shaw is an evolutionary biologist, who studies evolutionary change in nature. She is concerned with stressors such as climate change and population fragmentation and their effects on evolutionary change in populations. In early work with David N. Reznick, Frank H. Shaw and Helen Rodd, Ruth Shaw examined the effects of predator fish on the experimental evolution of subsequent guppy generations. They studied guppy populations over an 11-year period. They found that descendant guppies who were not directly affected by predation evolved in ways that resembled the life histories of guppies who had lived in predator-free communities. They also found that guppies could evolve extremely quickly, at a rate thousands of darwins faster than the rates of evolutionary changes observed in the fossil record.
Ruth Geyer Shaw | Research
The main ideas of evolution may be summarised as follows:
Introduction to evolution | Simple overview
The majority view then (and now) was that geographical separation is the primary force in species splitting (or allopatry) and secondarily was the increased sterility of crosses between incipient species.
George Romanes | Romanes on evolution
Rafinesque was one of the first to use the term "evolution" in the context of biological speciation. Rafinesque proposed a theory of evolution before Charles Darwin. In a letter in 1832, Rafinesque wrote: The truth is that Species and perhaps Genera also, are forming in organized beings by gradual deviations of shapes, forms and organs, taking place in the lapse of time. There is a tendency to deviations and mutations through plants and animals by gradual steps at remote irregular periods. This is a part of the great universal law of perpetual mutability in everything. Thus it is needless to dispute and differ about new genera, species and varieties.
Constantine Samuel Rafinesque | Evolution
Bacterial evolution may refer to the biological evolution of bacteria as studied in:
Bacterial evolution | Introduction
Outline of evolution
Outline of biology | Evolution