Concepts and models used in evolutionary biology, such as natural selection, have many applications. Artificial selection is the intentional selection of traits in a population of organisms. This has been used for thousands of years in the domestication of plants and animals. More recently, such selection has become a vital part of genetic engineering, with selectable markers such as antibiotic resistance genes being used to manipulate DNA. Proteins with valuable properties have evolved by repeated rounds of mutation and selection (for example modified enzymes and new antibodies) in a process called directed evolution. Understanding the changes that have occurred during an organism's evolution can reveal the genes needed to construct parts of the body, genes which may be involved in human genetic disorders.
Applications
Evolution
Evolution | Applications
domestication of plants and animals, genetic engineering, etc. Artificial selection is the intentional selection of traits in a population of organisms. This has been used for thousands of years in the domestication of plants and animals, genetic engineering Understanding the changes that have occurred during an organism's evolution can reveal the genes needed to construct parts of the body, genes which may be involved in human genetic disorders. The biology of regeneration, asexual reproduction, metamorphosis, and the growth and differentiation of stem cells in the adult organism.
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
Charles Darwin and Alfred Russel Wallace
assistant
when was the first one born?
user
Shrewsbury, Shropshire
assistant
did he suffer from any illness?
user
He had "an uncomfortable palpitation of the heart".
assistant
did he publish anything?
user
Yes, his theory of evolution with compelling evidence in his 1859 book "On the Origin of Species".
assistant
what does modern synthesis state about evolution?
user
It explained patterns observed across species in populations, through fossil transitions in palaeontology, and complex cellular mechanisms in developmental biology.
assistant
what is the last type of biology about?
user
It is the study of the process by which animals and plants grow and develop.
assistant
does it have any model for organisms?
user
Sorry. I cannot find the answer based on the context.
assistant
where has the study of evolution been applied to?
user
It has been used as a model organism in many evolution experiments.
Phi X 174 | Evolution
Evolutionary biology, in particular the understanding of how organisms evolve through natural selection, is an area of science with many practical applications. Creationists often claim that the theory of evolution lacks any practical applications; however, this claim has been refuted by scientists.
Applications of evolution | Introduction
Concepts and models used in evolutionary biology, such as natural selection, have many applications. Artificial selection is the intentional selection of traits in a population of organisms. This has been used for thousands of years in the domestication of plants and animals. More recently, such selection has become a vital part of genetic engineering, with selectable markers such as antibiotic resistance genes being used to manipulate DNA. Proteins with valuable properties have evolved by repeated rounds of mutation and selection (for example modified enzymes and new antibodies) in a process called directed evolution. Understanding the changes that have occurred during an organism's evolution can reveal the genes needed to construct parts of the body, genes which may be involved in human genetic disorders.
Evolution | Applications
The evolutionary approach is key to much current research in biology that does not set out to study evolution per se, especially in organismal biology and ecology. For example, evolutionary thinking is key to life history theory. Annotation of genes and their function relies heavily on comparative, that is evolutionary, approaches. The field of evolutionary developmental biology investigates how developmental processes work by using the comparative method to determine how they evolved.
Applications of evolution | Wider biology
Studies use evidence to predict how organisms evolved in the past and apply this evidence to the present. Both models of evolution can not only be seen between species, but also within a species. This is shown in a study done on the body size evolution in the radiolarian Pseudocubus vema. This study presents evidence of a species exhibiting punctuated and gradual evolution, while also having periods of relative stasis. Another study also used body size and looked at both micro-evolutionary patterns and fossil records. The study uses quantitative data to make conclusions and is an example of another study using body size as an indicator of evolution.
Punctuated gradualism | Studies
These same models can be applied to studying the evolution of human preferences and ideologies. Many variants on these models have been developed, which incorporate weak selection, mutual population structure, stochasticity, etc. These models have relevance also to the generation and maintenance of tissues in mammals, since an understanding of tissue cell kinetics, architecture, and development from adult stem cells has important implications for aging and cancer.
Evolutionary dynamics | Introduction
Some questions biologists have attempted to answer include: Why do some organisms have gamete dimorphism?
Evolution of sexual reproduction | Questions
These comparisons have allowed biologists to build a "relationship tree" of the evolution of life on Earth. They have even allowed scientists to unravel the relationships between organisms whose common ancestors lived such a long time ago that no real similarities remain in the appearance of the organisms.
Introduction to evolution | Molecular biology
"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
The cladogram is from Matthee et al., 2004, based on nuclear and mitochondrial gene analysis.
Leporidae | Evolution
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
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
One study focuses on how efforts to apply only one mode of evolution to a phenomenon can be inaccurate. It supports how difficult it can be to show that only one mode of evolution is at play at any given time. Another study also displays the importance of considering both models. The study supports that there can always be both models at play at any time. Another related study focuses on the extent of undefined area when trying to compare the two modes of evolution making it difficult to isolate one model. There will always be variance in environments. Some environments present challenges that require quick adaptation for survival, while others are relatively stable.
Punctuated gradualism | Studies
The reader should be aware that numerous phage experimental adaptations were performed in the early decades of phage study.
Bacteriophage experimental evolution | <a href="Experimental%20adaptation">Experimental adaptation</a>
The extended organism principle also justifies the Gaia Hypothesis and considers what we can translate from micro to macro, whether principles that govern termites offer a perspective on mind. He is an adviser to the Microbes Mind Forum and Professor of Biology at the State University of New York College of Environmental Science and Forestry (SUNY-ESF) in Syracuse, New York. Under a grant from the Templeton Foundation, he has been a visiting scholar at Cambridge University, writing his third book, currently titled "Biology's Second Law: Evolution, Purpose and Desire", which builds the case that evolution operates through the complementary principles of Darwinian natural selection (biology’s "First Law") coupled to homeostasis (biology’s "Second Law").
J. Scott Turner | Overview
"See also Basic principles (above)"
Outline of evolution | Evolutionary theory and modelling
Experimental evolution has been used in various formats to understand underlying evolutionary processes in a controlled system. Experimental evolution has been performed on multicellular and unicellular eukaryotes, prokaryotes, and viruses. Similar works have also been performed by directed evolution of individual enzyme, ribozyme and replicator genes.
Experimental evolution | Modern
orthogenesis). In reality, the evolution of an organism has no "objective" and is only showing increasing ability of successive generations to survive and reproduce in its environment; and increased suitability is only defined in relation to this environment. Biologists do not consider any one species, such as humans, to be more "highly evolved" or "advanced" than another. Certain sources have been criticized for indicating otherwise due to a tendency to evaluate nonhuman organisms according to anthropocentric standards rather than more objective ones. Evolution also does not require that organisms become more complex. Although the history of life shows an apparent trend towards the evolution of biological complexity, there is a question if this appearance of increased complexity is real, or if it comes from neglecting the fact that the majority of life on Earth has always consisted of prokaryotes.
Objections to evolution | Defining evolution
This seemed to apply in matters both of evolution and gene pool makeup. The reviewers found that some researchers seemed to have shifted their categories and methods to maintain this "special case" outlook.
Cheikh Anta Diop | Critique of previous scholarship on Africa
Quantum evolution – quasispecies model
Index of evolutionary biology articles | Q
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
The basic mechanisms of evolution are applied directly or indirectly to come up with novel designs or solve problems that are difficult to solve otherwise. The research generated in these applied fields in turn contribute to progress, especially thanks to work on evolution in computer science and engineering fields such as mechanical engineering.
Evolutionary biology | Subfields
paleoanthropology – paleobiology – paleobotany – paleontology – paleozoology (of vertebrates – of invertebrates) – parallel evolution – paraphyletic – particulate inheritance – peppered moth – peppered moth evolution – peripatric speciation – phenotype – phylogenetics – phylogeny – phylogenetic tree – "Pikaia" – Plant evolution – polymorphism (biology) – population – population bottleneck – population dynamics – population genetics – preadaptation – prehistoric archaeology – "Principles of Geology" – George R. Price – Price equation – punctuated equilibrium
Index of evolutionary biology articles | P
The evolutionary processes of speciation and extinction can be modelled with a stochastic “birth-death model” (BDM), which is an important component in the study of macroevolution. A BDM assigns each species a certain probability of splitting (formula_1) or going extinct (formula_2) per interval of time. This gives rise to an exponential distribution, with the number of species in a particular clade "N" at any time "t" given by formula_3, although this expression only gives the expected value when formula_4 and formula_5 are large (see below).
Push of the past | Birth-Death modelling in evolutionary studies
This allows for detailed measurements of evolutionary processes, for example epistasis, evolvability, adaptive constraint fitness landscapes, and neutral networks.
Directed evolution | Evolution studies
Due to the large mammalian homology, ADAM7 is primarily studied in "Mus Musculus".
ADAM7 | Model Organisms
A major technological application of evolution is artificial selection, which is the intentional selection of certain traits in a population of organisms. Humans have used artificial selection for thousands of years in the domestication of plants and animals. More recently, such selection has become a vital part of genetic engineering, with selectable markers such as antibiotic resistance genes being used to manipulate DNA in molecular biology. It is also possible to use repeated rounds of mutation and selection to evolve proteins with particular properties, such as modified enzymes or new antibodies, in a process called directed evolution.
Applications of evolution | Artificial selection
The study of natural evolution is traditionally based on extant organisms and their genes. However, research is fundamentally limited by the lack of fossils (and particularly the lack of ancient DNA sequences) and incomplete knowledge of ancient environmental conditions. Directed evolution investigates evolution in a controlled system of genes for individual enzymes, ribozymes and replicators (similar to experimental evolution of eukaryotes, prokaryotes and viruses). DE allows control of selection pressure, mutation rate and environment (both the abiotic environment such as temperature, and the biotic environment, such as other genes in the organism). Additionally, there is a complete record of all evolutionary intermediate genes.
Directed evolution | Evolution studies
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
Modern research has suggested that, due to horizontal gene transfer, this "tree of life" may be more complicated than a simple branching tree since some genes have spread independently between distantly related species. To solve this problem and others, some authors prefer to use the "Coral of life" as a metaphor or a mathematical model to illustrate the evolution of life. This view dates back to an idea briefly mentioned by Darwin but later abandoned. Past species have also left records of their evolutionary history. Fossils, along with the comparative anatomy of present-day organisms, constitute the morphological, or anatomical, record.
Evolution | Common descent
The bristle worm, a marine annelid, has been modified. It is of interest due to its reproductive cycle being synchronized with lunar phases, regeneration capacity and slow evolution rate. Cnidaria such as "Hydra" and the sea anemone "Nematostella vectensis" are attractive model organisms to study the evolution of immunity and certain developmental processes. Other animals that have been genetically modified include snails, geckos, turtles, crayfish, oysters, shrimp, clams, abalone and sponges.
Genetically modified organism | Other
Knowledge of evolution by gene duplication has advanced more rapidly in the past 15 years due to new genomic data, more powerful computational methods of comparative inference, and new evolutionary models.
Evolution by gene duplication | Introduction
A common claim of creationists is that evolution has never been observed. Challenges to such objections often come down to debates over how evolution is defined (see the Defining evolution section above). Under the conventional biological definition of "evolution", it is a simple matter to observe evolution occurring. Evolutionary processes, in the form of populations changing their genetic composition from generation to generation, have been observed in different scientific contexts, including the evolution of fruit flies, mice, and bacteria in the laboratory, and of tilapia in the field. Such studies on experimental evolution, particularly those using microorganisms, are now providing important insights into how evolution occurs, especially in the case of antibiotic resistance.
Objections to evolution | Lack of observation
The long-term evolution experiment was designed as an open-ended means of empirical examination of central features of evolution. The experiment was begun with three principal goals: As the experiment has continued, its scope has grown as new questions in evolutionary biology have arisen that it can be used to address, as the populations' evolution has presented new phenomena to study, and as technology and methodological techniques have advanced. The use of "E. coli" as the experimental organism has allowed many generations and large populations to be studied in a relatively short period of time. Moreover, due to the long use of "E.
E. coli long-term evolution experiment | Experimental approach
The bristle worm, a marine annelid, has been modified. It is of interest due to its reproductive cycle being synchronised with lunar phases, regeneration capacity and slow evolution rate. Cnidaria such as "Hydra" and the sea anemone "Nematostella vectensis" are attractive model organisms to study the evolution of immunity and certain developmental processes. Other organisms that have been genetically modified include snails, geckos, turtles, crayfish, oysters, shrimp, clams, abalone and sponges.
Genetically modified animal | Other
Most cellular models have been based on unicellular microbes. Since these simple organisms lack a complex neural network, computational modeling focuses on the various biochemical pathways of the cells, such as transcription, translation, post-translational modification, and protein-protein interactions. A variety of algorithms and programs exist that attempt to model these type of interactions.
Evolution in Variable Environment | Computational framework
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
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 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, 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.
Evolutionary ecology | Evolutionary models
LEM has been modified from optimization domain to classification domain by augmented LEM with ID3 (February 2013 by M. Elemam Shehab, K. Badran, M. Zaki and Gouda I. Salama).
Learnable evolution model | Introduction
For a time-independent Hamiltonian "H", where "H" is Free Hamiltonian,
Schrödinger picture | Summary comparison of evolution in all pictures
Outline of evolution
Outline of biology | Evolution
Models are those organisms with a wealth of biological data that make them attractive to study as examples for other species and/or natural phenomena that are more difficult to study directly. Continual research on these organisms focus on a wide variety of experimental techniques and goals from many different levels of biology—from ecology, behavior and biomechanics, down to the tiny functional scale of individual tissues, organelles and proteins. Inquiries about the DNA of organisms are classed as genetic models (with short generation times, such as the fruitfly and nematode worm), experimental models, and genomic parsimony models, investigating pivotal position in the evolutionary tree.
Model organism | Selection
The cladogram is based on Betancur-R et al., 2017.
Percomorpha | Evolution
Therefore, comparisons can be made for the exact molecular changes in evolved strains during adaptation to novel conditions.
Bacteriophage experimental evolution | Introduction
unit of selection
Index of evolutionary biology articles | U
In order to gain insight into "why" animals evolve swarming behaviour, scientists have turned to evolutionary models that simulate populations of evolving animals. Typically these studies use a genetic algorithm to simulate evolution over many generations in the model. These studies have investigated a number of hypotheses explaining why animals evolve swarming behaviour, such as the selfish herd theory, the predator confusion effect, the dilution effect, and the many eyes theory.
Shoaling and schooling | Evolutionary models
No evidence has thus far been discovered that may reject or prefer one of the three models.
Hypselostoma lacrima | Ecology, conservation and evolution
variety (botany) – Vertebrate paleontology (a.k.a. vertebrate paleobiology or paleozoology) – viral evolution – "The Voyage of the Beagle" – vestigiality
Index of evolutionary biology articles | V
The implication from such a find is that modern reptiles and birds arose from a common ancestor.
Introduction to evolution | Fossil record
coli" as a principle model organism in molecular biology, a wide array of tools, protocols, and procedures were available for studying changes at the genetic, phenotypic, and physiological levels. The bacteria can also be frozen and preserved while remaining viable. This has permitted the creation of what Lenski describes as a "frozen fossil record" of samples of evolving populations that can be revived at any time. This frozen fossil record allows populations to be restarted in cases of contamination or other disruption in the experiment, and permits the isolation and comparison of living exemplars of ancestral and evolved clones. Lenski chose an "E.
E. coli long-term evolution experiment | Experimental approach
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
The evolution of anoles has been widely studied, and they have been described as a "textbook example of adaptive radiation and convergent evolution". Especially the widespread convergent evolution seen in anoles living in the Greater Antilles has attracted the attention of scientists, and resulted in comparisons with the Darwin's finches of the Galápagos Islands, lemurs of Madagascar and cichlid fish in the African Great Lakes.
Dactyloidae | Evolution
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
Experimental evolution studies are a means of testing evolutionary theory under carefully designed, reproducible experiments. Given enough time, space, and money, any organism could be used for experimental evolution studies. However, those with rapid generation times, high mutation rates, large population sizes, and small sizes increase the feasibility of experimental studies in a laboratory context. For these reasons, bacteriophages (i.e. viruses that infect bacteria) are especially favored by experimental evolutionary biologists. Bacteriophages, and microbial organisms, can be frozen in stasis, facilitating comparison of evolved strains to ancestors. Additionally, microbes are especially labile from a molecular biologic perspective. Many molecular tools have been developed to manipulate the genetic material of microbial organisms, and because of their small genome sizes, sequencing the full genomes of evolved strains is trivial.
Bacteriophage experimental evolution | 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
"D. subobscura" has been regarded as a model organism for its use in evolutionary-biological studies.
Drosophila subobscura | Introduction
Current research in evolutionary biology covers diverse topics and incorporates ideas from diverse areas, such as molecular genetics and computer science. First, some fields of evolutionary research try to explain phenomena that were poorly accounted for in the modern evolutionary synthesis. These include speciation, the evolution of sexual reproduction, the evolution of cooperation, the evolution of ageing, and evolvability. Second, biologists ask the most straightforward evolutionary question: "what happened and when?". This includes fields such as paleobiology, as well as systematics and phylogenetics.
Evolutionary biology | Current research topics
Select domains of ZC3H12B are conserved in most vertebrates, arthropods and annelids. There are not conserved domains in domains bacteria or archaea. There were not significantly conserved domains in yeasts, plants or protists.
ZC3H12B | Evolution
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
Evolutionary research is concerned with the origin and descent of species, as well as their change over time, and includes scientists from many taxonomically oriented disciplines. For example, it generally involves scientists who have special training in particular organisms such as mammalogy, ornithology, herpetology, or entomology, but use those organisms as systems to answer general questions about evolution. Evolutionary biology is partly based on paleontology, which uses the fossil record to answer questions about the mode and tempo of evolution, and partly on the developments in areas such as population genetics and evolutionary theory. Following the development of DNA fingerprinting techniques in the late 20th century, the application of these techniques in zoology has increased the understanding of animal populations.
Zoology | Evolutionary
Evolutionary research is concerned with the origin and descent of species, and their change over time. It employs scientists from many taxonomically oriented disciplines; for example, those with special training in particular organisms such as mammalogy, ornithology, botany, or herpetology, but are of use in answering more general questions about evolution. Evolutionary biology is partly based on paleontology, which uses the fossil record to answer questions about the mode and tempo of evolution, and partly on the developments in areas such as population genetics. In the 1980s, developmental biology re-entered evolutionary biology after its initial exclusion from the modern synthesis through the study of evolutionary developmental biology.
Biology | Evolutionary
Joshi continues his early researches on Drosophila but has now combined his evolution studies with theoretical work using computer simulations. His researches focuses on the inter-relations between the genetics of organisms and their ecology and the influence of these factors in their evolutionary path. His laboratory studies various evolutionary aspects such as the rate of development, patterns of progeny and ageing and investigates the development of competitive abilities and stress resistance in organisms. His researches have been documented by way of a number of articles and several of them have been listed by many major online article repositories such as Google Scholar, ResearchGate, Academic Tree and PubFacts.
Amitabh Joshi | Legacy
Phylogenetics is the study of the evolutionary relatedness of organisms. Laboratory phylogenetics is the study of the evolutionary relatedness of laboratory-evolved organisms. An advantage of laboratory phylogenetics is the exact evolutionary history of an organism is known, rather than estimated as is the case for most organisms.
Bacteriophage experimental evolution | Laboratory <a href="phylogenetics">phylogenetics</a>
Evolutionary theories continue to generate testable predictions and explanations about living and fossilized organisms.
Evolution as fact and theory | Theory
...the principles can be applied equally to genes, organisms, populations, species, and at opposite ends of the scale, prebiotic molecules and ecosystems." (1970, pp. 1-2) Elisabeth Lloyd's book "The Structure and Confirmation of Evolutionary Theory" provides a basic "philosophical" introduction to the debate.
Unit of selection | Fundamental theory
An organism that learns to modulate its behavior and gene expression based on temporal interrelationships between environmental factors possesses a competitive advantage of over other organisms that are unable to make such predictions. For example, learning when nutrients are going to be present in the environment allows the organism to selectively express genes that will take up the food source, thus allowing the organism to harvest energy. Modeling these type of behaviors of even simple bacteria poses certain challenges. Given the diversity of biological systems, it would appear that the number of behavior responses to an environmental change would be nearly infinite.
Evolution in Variable Environment | Overview
The organism used is decided by the experimenter, based on the hypothesis to be tested. Many generations are required for adaptive mutation to occur, and experimental evolution via mutation is carried out in viruses or unicellular organisms with rapid generation times, such as bacteria and asexual clonal yeast. Polymorphic populations of asexual or sexual yeast, and multicellular eukaryotes like Drosophila, can adapt to new environments through allele frequency change in standing genetic variation. Organisms with longer generations times, although costly, can be used in experimental evolution. Laboratory studies with foxes and with rodents (see below) have shown that notable adaptations can occur within as few as 10–20 generations and experiments with wild guppies have observed adaptations within comparable numbers of generations.
Experimental evolution | Introduction
Dramatic examples of entirely new and unique traits arising through mutation have been observed in recent years, such as the evolution of nylon-eating bacteria which developed new enzymes to efficiently digest a material that never existed before the modern era. There is no need to account for the creation of information when an organism is considered together with the environment it evolved in. The information in the genome forms a record of how it was possible to survive in a particular environment. The information is gathered from the environment through trial and error, as mutating organisms either reproduce or fail.
Objections to evolution | Creation of information
Some critics have argued that researchers know so little about the environment in which "Homo sapiens" evolved that explaining specific traits as an adaption to that environment becomes highly speculative. Evolutionary psychologists respond that they do know many things about this environment, including the facts that present day humans' ancestors were hunter-gatherers, that they generally lived in small tribes, etc. Edward Hagen argues that the human past environments were not radically different in the same sense as the Carboniferous or Jurassic periods and that the animal and plant taxa of the era were similar to those of the modern world, as was the geology and ecology.
Evolutionary psychology | Testability of hypotheses
A widespread current model of the evolution of the first living organisms is that these were some form of prokaryotes, which may have evolved out of protocells, while the eukaryotes evolved later in the history of life. Some authors have questioned this conclusion, arguing that the current set of prokaryotic species may have evolved from more complex eukaryotic ancestors through a process of simplification. Others have argued that the three domains of life arose simultaneously, from a set of varied cells that formed a single gene pool. This controversy was summarized in 2005: There is no consensus among biologists concerning the position of the eukaryotes in the overall scheme of cell evolution.
Prokaryote | Evolution
Many of the human evolutionary developmental biology studies have been modeled after primate studies and consider the two together in a comparative model. Brain ontogeny and human life history evolution were looked at by Leigh, in a 2006 paper. He compares brain growth patterns for "Homo erectus" and "Homo sapiens" to get at the evolution of brain size and weight. Leigh found three different patterns, all of which pointed to the growth rate of "H. erectus" either matching or exceeding "H. erectus". He makes the case that this finding had wide application and relevance t the overall study of human evolution.
Human evolutionary developmental biology | Human and primate development
Computational evolutionary biology has enabled researchers to trace the evolution of a large number of organisms by measuring changes in their DNA, rather than through physical taxonomy or physiological observations alone. It has compared entire genomes permitting the study of more complex evolutionary events, such as gene duplication, horizontal gene transfer, and the prediction of factors important in speciation. It has also helped build complex computational models of populations to predict the outcome of the system over time and track and share information on an increasingly large number of species and organisms.
Evidence of common descent | Evidence from mathematical modeling and simulation
Below is a cladogram representing the evolutionary trends all the way up to and past Casea broilii.
Casea | Classification
"Evolution" captures both the history of an organism via its phylogeny, and the history of natural selection working on function to produce adaptations. There are several reasons why natural selection may fail to achieve optimal design (Mayr 2001:140–143; Buss et al. 1998). One entails random processes such as mutation and environmental events acting on small populations. Another entails the constraints resulting from early evolutionary development. Each organism harbors traits, both anatomical and behavioural, of previous phylogenetic stages, since many traits are retained as species evolve. Reconstructing the phylogeny of a species often makes it possible to understand the "uniqueness" of recent characteristics: Earlier phylogenetic stages and (pre-) conditions which persist often also determine the form of more modern characteristics.
Tinbergen's four questions | 2 Phylogeny (evolution)
The idea of evolution by natural selection was proposed by Charles Darwin in 1859, but evolutionary biology, as an academic discipline in its own right, emerged during the period of the modern synthesis in the 1930s and 1940s. It was not until the 1980s that many universities had departments of evolutionary biology. In the United States, many universities have created departments of "molecular and cell biology" or "ecology and evolutionary biology", in place of the older departments of botany and zoology. Palaeontology is often grouped with earth science. Microbiology too is becoming an evolutionary discipline, now that microbial physiology and genomics are better understood.
Evolutionary biology | History
In evolutionary biology and bio-medicine, the model is used to detect the presence of structured genetic variation in a group of individuals. The model assumes that alleles carried by individuals under study have origin in various extant or past populations. The model and various inference algorithms allow scientists to estimate the allele frequencies in those source populations and the origin of alleles carried by individuals under study. The source populations can be interpreted ex-post in terms of various evolutionary scenarios. In association studies, detecting the presence of genetic structure is considered a necessary preliminary step to avoid confounding.
Latent Dirichlet allocation | Evolutionary biology and bio-medicine
Nevo received a M.Sc and PhD (1964) from Hebrew University. His Ph.D thesis was entitled "Population studies of Anurans from the lower Cretaceous of Makhtesh Ramon, Israel". He founded the Institute of Evolution at Haifa in 1973. Nevo works with many evolutionary subjects, involving understanding and tracking of speciation processes, modifications of highly evolved traits (vision), climatic and geographic effects in sympatric speciation in insects, bacteria, fungi, mammals and crops. He is a proponent of evolutionary models where environmental stressors acting positively to shape genetic polymorphisms. The model of "Evolution Canyon" is a microscale open environment where two opposite slopes with contrasting climatic conditions have also finer biotic adaptations that have been researched at different biological scales, supporting the evolution in action generating evidence of sympatric speciation, and of particular impact and interest are the works in Drosophila and in wild barley.
Eviatar Nevo | Education
Reticulate evolution has played a key role in the evolution of some organisms such as bacteria and flowering plants. However, most methods for studying cladistics have been based on a model of strictly branching cladogeny, without assessing the importance of reticulate evolution. Reticulation at chromosomal, genomic and species levels fails to be modelled by a bifurcating tree. According to Ford Doolittle, an evolutionary and molecular biologist: “Molecular phylogeneticists will have failed to find the “true tree,” not because their methods are inadequate or because they have chosen the wrong genes, but because the history of life cannot properly be represented as a tree”.
Reticulate evolution | Models
The organisms below have become model organisms because they facilitate the study of certain characters or because of their genetic accessibility. For example, "E. coli" was one of the first organisms for which genetic techniques such as transformation or genetic manipulation has been developed. The genomes of all model species have been sequenced, including their mitochondrial/chloroplast genomes. Model organism databases exist to provide researchers with a portal from which to download sequences (DNA, RNA, or protein) or to access functional information on specific genes, for example the sub-cellular localization of the gene product or its physiological role.
Model organism | Selected model organisms
Darwin's theory of evolution by natural selection is the only scientific explanation for why an animal's behaviour is usually well adapted for survival and reproduction in its environment. However, claiming that a particular mechanism is well suited to the present environment is different from claiming that this mechanism was selected for in the past due to its history of being adaptive. The literature conceptualizes the relationship between function and evolution in two ways. On the one hand, function and evolution are often presented as separate and distinct explanations of behaviour. On the other hand, the common definition of adaptation, a central concept in evolution, is a trait that was functional to the reproductive success of the organism and that is thus now present due to being selected for; that is, function and evolution are inseparable.
Tinbergen's four questions | 1 Function (adaptation)
The primary reason for the use of model organisms in research is the evolutionary principle that all organisms share some degree of relatedness and genetic similarity due to common ancestry. The study of taxonomic human relatives, then, can provide a great deal of information about mechanism and disease within the human body that can be useful in medicine. Various phylogenetic trees for vertebrates have been constructed using comparative proteomics, genetics, genomics as well as the geochemical and fossil record. These estimations tell us that humans and chimpanzees last shared a common ancestor about 6 million years ago (mya). As our closest relatives, chimpanzees have a lot of potential to tell us about mechanisms of disease (and what genes may be responsible for human intelligence).
Model organism | Phylogeny and genetic relatedness
All I can presently say is that my chemical tools do not permit my assessment of intelligent design." He explained that he felt the explanations offered by evolution are incomplete, and he found it hard to believe that nature can produce the machinery of cells through random processes. On his website, he writes that "In biology, the mechanisms for such transformations are complete mysteries. I posit that the gross chemical changes needed for macroevolution (defined here as origin of the major organism groups, i.e. of body plans) are not understood and presently we cannot even suggest the mechanisms, let alone observe them…One day the requisite chemical basis might become apparent so that the questions can be answered.
James Tour | A Scientific Dissent From Darwinism
Gishlick notes that even the intelligent design textbook, "Of Pandas and People", would only receive a C. The claim that it is irrelevant is incorrect, as the experiment marked a major advance in studies of the origin of life, its results are still valid, and for teaching purposes it shows the methods of good experimental science.
Icons of Evolution | Miller–Urey experiment
The origins and history of ecosystems, species, genes and genomes, and organisms, and how these have changed over time is all part of the studies of how biodiversity has evolved and how it takes place. Ecology and Evolutionary biology in North America is based on research impact determined by the top 10% of ecology programs. The interactive web of organisms and environment are all part of what the field of Ecology explores. There have been studies in evolution that have worked to prove that "modern organisms have developed from ancestral ones." The reason that evolutionary biology is so interesting to learn about is because of the evolutionary processes that is the reason we have such a diversity of life on Earth.There are many processes that make up evolutionary biology that give great insight to how we came to be, some of which include natural selection, speciation, and common descent.
Ecology and Evolutionary Biology | Degrees in North America
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
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
By lifting images from their "natural" habitat she wished to demonstrate the evolutionary processes of technological advancement, economic expansion and positivistic adaptations to flora, fauna and humankind.
Katja Novitskova | Work
However, Darwin did not conceive the theory of evolution during the "Beagle"s voyage, later recounting that: it was equally evident that neither the action of the surrounding conditions, nor the will of the organisms (especially in the case of plants), could account for the innumerable cases in which organisms of every kind are beautifully adapted to their habitats of life—for instance, a woodpecker or a tree-frog to climb trees, or a seed for dispersal by hooks or plumes. I had always been much struck by such adaptations, and until these could be explained it seemed to me almost useless to endeavour to prove by indirect evidence that species have been modified.
Inception of Darwin's theory | Background
History of model organisms
History of research on Caenorhabditis elegans | See also
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"
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
It is aimed to simplify other models addressing the relationships within communities.
Evolutionary ecology | Evolutionary models
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
The wall is analogous to the complexity level of bacteria. We should expect evolution to wander increasingly further from this level of complexity, but it does not imply that evolution is driven towards increasing complexity. In response to Gould's (1997) critique, Turney (2000) presents a computational model in which there is a largest-scale trend towards increasing evolutionary versatility. This trend requires continual change. Although this model shows that largest-scale trends are compatible with evolutionary theory, the model has not yet been empirically confirmed.
Largest-scale trends in evolution | Theoretical perspective
Many microbial species have short generation times, easily sequenced genomes, and well-understood biology. They are therefore commonly used for experimental evolution studies. The bacterial species most commonly used for experimental evolution include "P. fluorescens" and "E. coli"(see below), while the Yeast "S. cerevisiae" has been used as a model for the study of eukaryotic evolution.
Experimental evolution | Microbes
Evolution@Home is the first parallel computing project for evolutionary biology. The aim of Evolution@Home is to improve understanding of evolutionary processes. This is achieved by simulating individual-based models. The first such model targets the accumulation of mutations in asexual populations and is implemented in Simulator005. The software of Evolution@Home is not the first to simulate this, but previous simulations were hampered by lack of memory (needed for looking at large populations) and lack of computing power (needed for observing long-term evolution and many different parameter combinations). The possibility of parallel computing has allowed Evolution@Home to move the realism of simulated parameter combinations significantly towards observed reality.
Evolution@Home | 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
Breeding together different populations of this blind fish produced some offspring with functional eyes, since different mutations had occurred in the isolated populations that had evolved in different caves. This helped identify genes required for vision and pigmentation, such as crystallins and the melanocortin 1 receptor. Similarly, comparing the genome of the Antarctic icefish, which lacks red blood cells, to close relatives such as the Antarctic rockcod revealed genes needed to make these blood cells.
Applications of evolution | Medicine
Tattersall maintains that the notion of human evolution as a linear trudge from primitivism to perfection is incorrect. Whereas the Darwinian approach to evolution may be viewed as a fine-tuning of characteristics guided by natural selection, Tattersall takes a more generalist view. Tattersall claims that individual organisms are mind-bogglingly complex and integrated mechanisms; they succeed or fail as the sum of their parts, and not because of a particular characteristic. In terms of human evolution, Tattersall believes the process was more a matter of evolutionary experimentation in which a new species entered the environment, competed with other life forms, and either succeeded, failed, or became extinct within that environment: "To put it in perspective, consider the fact that the history of diversity and competition among human species began some five million years ago when there were at least four different human species living on the same landscape.
Ian Tattersall | Career
With the rapid expansion of human understanding of cell, molecular, and chemical biology, a vast set of data has been generated on the metabolic pathways, signal-transductional pathways, and gene regulatory networks. Cellular modeling attempts to analyze and visualize these pathways with the help of computers. A substantial portion of EVE is devoted to writing algorithms, data structures, and visualization tools for these biological systems.
Evolution in Variable Environment | Cellular model