Chasing Shadows: Natural Selection and Adaptation
... (1982) offer the example of individual selection without a change in gene frequencies. Consider a case of extreme heterosis. For some locus with two alleles A and a, the heterozygotes (Aa) are on average extremely robust, while the homozygous condition (AA or aa) is lethal. Only the heterozygotes su ...
... (1982) offer the example of individual selection without a change in gene frequencies. Consider a case of extreme heterosis. For some locus with two alleles A and a, the heterozygotes (Aa) are on average extremely robust, while the homozygous condition (AA or aa) is lethal. Only the heterozygotes su ...
Life at Its Many Levels
... A genome is the entire “book” of genetic instructions an organism inherits The nucleus of each human cell packs a genome that is about 3.2 billion chemical letters long ...
... A genome is the entire “book” of genetic instructions an organism inherits The nucleus of each human cell packs a genome that is about 3.2 billion chemical letters long ...
Can Modern Evolutionary Theory Explain Macroevolution?
... of the Synthetic Theory (ST) that emerged during the ES from the union of ideas and evidence from genetics, systematics, natural history, and paleontology, the processes of evolution within species, accumulated over time, explain the origin and diversification of higher taxa (Futuyma 1979, Mayr and ...
... of the Synthetic Theory (ST) that emerged during the ES from the union of ideas and evidence from genetics, systematics, natural history, and paleontology, the processes of evolution within species, accumulated over time, explain the origin and diversification of higher taxa (Futuyma 1979, Mayr and ...
Can Modern Evolutionary Theory Explain Macroevolution?
... of the Synthetic Theory (ST) that emerged during the ES from the union of ideas and evidence from genetics, systematics, natural history, and paleontology, the processes of evolution within species, accumulated over time, explain the origin and diversification of higher taxa (Futuyma 1979, Mayr and ...
... of the Synthetic Theory (ST) that emerged during the ES from the union of ideas and evidence from genetics, systematics, natural history, and paleontology, the processes of evolution within species, accumulated over time, explain the origin and diversification of higher taxa (Futuyma 1979, Mayr and ...
Perspective Evolution Is an Experiment
... differed in several morphological features compared its wild progenitor, which is commonly called “teosinte” (for a review, see Doebley 2004). There is no such thing as an ear of corn in the wild; instead, teosinte plants have hard, triangular seeds that are organized within a single row. Maize typi ...
... differed in several morphological features compared its wild progenitor, which is commonly called “teosinte” (for a review, see Doebley 2004). There is no such thing as an ear of corn in the wild; instead, teosinte plants have hard, triangular seeds that are organized within a single row. Maize typi ...
Ch 14
... Exploration of new lands revealed a staggering diversity of life (continued) – The vast numbers of species observed allowed naturalists to see patterns that had not emerged before – They noticed, for example, that each area had its own distinctive set of species – They also observed that some spec ...
... Exploration of new lands revealed a staggering diversity of life (continued) – The vast numbers of species observed allowed naturalists to see patterns that had not emerged before – They noticed, for example, that each area had its own distinctive set of species – They also observed that some spec ...
Mate-recognition and species boundaries in the ascomycetes
... trees sometimes reflect the species phylogeny (Turgeon 1998; O’Donnell et al. 2004). This is not always the case however. There is phylogenetic evidence of introgression of MAT genes between non-sister species in Neurospora (Strandberg et al. 2010), and Fusarium (Martin et al. 2011b). In Ophiostoma, ...
... trees sometimes reflect the species phylogeny (Turgeon 1998; O’Donnell et al. 2004). This is not always the case however. There is phylogenetic evidence of introgression of MAT genes between non-sister species in Neurospora (Strandberg et al. 2010), and Fusarium (Martin et al. 2011b). In Ophiostoma, ...
Unit 2: Change and Diversity of Life
... inherited characteristic that increases an organism’s chance of ...
... inherited characteristic that increases an organism’s chance of ...
Deme 1.0 - BioQUEST Curriculum Consortium
... In population genetics, evolutionary forces are defined as processes that cause allele frequencies to change. Four such forces are generally recognized: 1. Selection — differential survival or reproduction of individuals with different genotypes; 2. Genetic drift — random changes in allele frequency ...
... In population genetics, evolutionary forces are defined as processes that cause allele frequencies to change. Four such forces are generally recognized: 1. Selection — differential survival or reproduction of individuals with different genotypes; 2. Genetic drift — random changes in allele frequency ...
Darwin and Feminism: Preliminary Investigations for
... proliferation, or by providing a hostile, or conducive, environment, to select from the proliferation of life forms, those which survive and provide reproductive continuity with succeeding generations. As its name suggests, natural selection is the process, or rather processes (for it includes both ...
... proliferation, or by providing a hostile, or conducive, environment, to select from the proliferation of life forms, those which survive and provide reproductive continuity with succeeding generations. As its name suggests, natural selection is the process, or rather processes (for it includes both ...
Divergent Selection Drives Genetic Differentiation in an
... genetic changes influencing divergence before they become confounded with other species differences. Nevertheless, despite the rich theoretical and empirical history of clines and hybrid ...
... genetic changes influencing divergence before they become confounded with other species differences. Nevertheless, despite the rich theoretical and empirical history of clines and hybrid ...
Paleontological Patterns, Macroecological Dynamics and the
... cancel each other out. Put another way, the probability that directional natural selection can act on an entire species (as if it were, in fact, a single panmictic population) is vanishingly small. If punctuated equilibria served the dual purpose of integrating existing evolutionary theory centered ...
... cancel each other out. Put another way, the probability that directional natural selection can act on an entire species (as if it were, in fact, a single panmictic population) is vanishingly small. If punctuated equilibria served the dual purpose of integrating existing evolutionary theory centered ...
Chapter 3: Darwinian Natural Selection
... organisms and a logical outcome that follows, as a matter of simple mathematics, if the four postulates are true.These cartoons show how the theory might work in a population of chili plants whose fruits are attacked by packrats. If the chilies vary in the spiciness of their fruit, and if packrats p ...
... organisms and a logical outcome that follows, as a matter of simple mathematics, if the four postulates are true.These cartoons show how the theory might work in a population of chili plants whose fruits are attacked by packrats. If the chilies vary in the spiciness of their fruit, and if packrats p ...
Theoretical perspectives on rapid evolutionary change
... many smaller QTL are typically found as well (average minimum QTL: 7.0 ± 0.47% of the phenotypic variance; average number of QTL: 6.1 ± 0.3). Moreover, many small-effect QTL certainly remain undetected. Indeed, in the earlier mentioned studies, the total percentage of phenotypic variation explained ...
... many smaller QTL are typically found as well (average minimum QTL: 7.0 ± 0.47% of the phenotypic variance; average number of QTL: 6.1 ± 0.3). Moreover, many small-effect QTL certainly remain undetected. Indeed, in the earlier mentioned studies, the total percentage of phenotypic variation explained ...
Exam Review 2015
... The movement of alleles from one population to another due to the migration of individuals. ...
... The movement of alleles from one population to another due to the migration of individuals. ...
Evolution and Biodiversity: Origin and
... The number of species in any given place is the most common measure of biodiversity. But estimating the total number of species on Earth is a challenge. Many species are easy to find, such as the birds or small mammals you might see in your neighborhood. Others are not so easy to find. Some species ...
... The number of species in any given place is the most common measure of biodiversity. But estimating the total number of species on Earth is a challenge. Many species are easy to find, such as the birds or small mammals you might see in your neighborhood. Others are not so easy to find. Some species ...
Adaptive Evolution
... Natural selection is a driving force in evolution and can generate populations that are better adapted to survive and successfully reproduce in their environments. But natural selection cannot produce the perfect organism. Natural selection can only select on existing variation in the population; it ...
... Natural selection is a driving force in evolution and can generate populations that are better adapted to survive and successfully reproduce in their environments. But natural selection cannot produce the perfect organism. Natural selection can only select on existing variation in the population; it ...
The Evolution of Multimeric Protein Assemblages R esearch article
... resultant theory demonstrates that the likelihoods of alternative pathways for the emergence of protein complexes depend strongly on the effective population size. Nonetheless, it is equally clear that further advancements in this area will require comparative studies on the fitness consequences of ...
... resultant theory demonstrates that the likelihoods of alternative pathways for the emergence of protein complexes depend strongly on the effective population size. Nonetheless, it is equally clear that further advancements in this area will require comparative studies on the fitness consequences of ...
Brief Contents
... of evolution 258 13.3 Scientists can observe natural selection in action 259 13.4 The study of fossils provides strong evidence for evolution 260 13.5 Many types of scientific evidence support the evolutionary view of life 262 13.6 Homologies indicate patterns of descent that can be shown on an evol ...
... of evolution 258 13.3 Scientists can observe natural selection in action 259 13.4 The study of fossils provides strong evidence for evolution 260 13.5 Many types of scientific evidence support the evolutionary view of life 262 13.6 Homologies indicate patterns of descent that can be shown on an evol ...
PowerPoint
... cope with the environment became larger and stronger, while those not used deteriorated. ...
... cope with the environment became larger and stronger, while those not used deteriorated. ...
No Slide Title - s3.amazonaws.com
... • 3. Competition for Mates Many species have so much competition for mates that interesting adaptations result. For example, the females of many bird species prefer to mate with males that have colorful feathers. ...
... • 3. Competition for Mates Many species have so much competition for mates that interesting adaptations result. For example, the females of many bird species prefer to mate with males that have colorful feathers. ...
Effective population size and patterns of molecular evolution and
... Consider the effects of genetic drift on selectively neutral variants, assuming that the population is closed (there is no migration from elsewhere) and panmictic. We also ignore the possibility of mutation. Assume that there are two alternative variants at an autosomal site, A1 and A2, with frequen ...
... Consider the effects of genetic drift on selectively neutral variants, assuming that the population is closed (there is no migration from elsewhere) and panmictic. We also ignore the possibility of mutation. Assume that there are two alternative variants at an autosomal site, A1 and A2, with frequen ...
A. Directional Selection
... Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential for a species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited re ...
... Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential for a species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited re ...
Evolution of Darwin`s finches caused by a rare climatic event
... experimental data on fruit flies (Dacus) that hybridization could enhance adaptation to extreme climatic conditions through the production of novel genotypes. Thus two evolutionary forces, selection and hybridProc.R. Soc. Lond.B (1993) 251, 111-117 ...
... experimental data on fruit flies (Dacus) that hybridization could enhance adaptation to extreme climatic conditions through the production of novel genotypes. Thus two evolutionary forces, selection and hybridProc.R. Soc. Lond.B (1993) 251, 111-117 ...
Evolution
Evolution is change in the heritable traits of biological populations over successive generations. Evolutionary processes give rise to diversity at every level of biological organisation, including the levels of species, individual organisms, and molecules.All of life on earth shares a common ancestor known as the last universal ancestor, which lived approximately 3.5–3.8 billion years ago. Repeated formation of new species (speciation), change within species (anagenesis), and loss of species (extinction) throughout the evolutionary history of life on Earth are demonstrated by shared sets of morphological and biochemical traits, including shared DNA sequences. These shared traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct a biological ""tree of life"" based on evolutionary relationships (phylogenetics), using both existing species and fossils. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, to fossilized multicellular organisms. Existing patterns of biodiversity have been shaped both by speciation and by extinction. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates of Earth's current species range from 10 to 14 million, of which about 1.2 million have been documented.In the mid-19th century, Charles Darwin formulated the scientific theory of evolution by natural selection, published in his book On the Origin of Species (1859). Evolution by natural selection is a process demonstrated by the observation that more offspring are produced than can possibly survive, along with three facts about populations: 1) traits vary among individuals with respect to 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). Thus, in successive generations members of a population are replaced by progeny of parents better adapted to survive and reproduce in the biophysical environment in which natural selection takes place. This teleonomy is the quality whereby the process of natural selection creates and preserves traits that are seemingly fitted for the functional roles they perform. Natural selection is the only known cause of adaptation but not the only known cause of evolution. Other, nonadaptive causes of microevolution include mutation and genetic drift.In the early 20th century the modern evolutionary synthesis integrated classical genetics with Darwin's theory of evolution by natural selection through the discipline of population genetics. The importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis, evolutionism, and other beliefs about innate ""progress"" within the largest-scale trends in evolution, became obsolete scientific theories. Scientists continue to study various aspects of evolutionary biology by forming and testing hypotheses, constructing mathematical models of theoretical biology and biological theories, using observational data, and performing experiments in both the field and the laboratory. Evolution is a cornerstone of modern science, accepted as one of the most reliably established of all facts and theories of science, based on evidence not just from the biological sciences but also from anthropology, psychology, astrophysics, chemistry, geology, physics, mathematics, and other scientific disciplines, as well as behavioral and social sciences. Understanding of evolution has made significant contributions to humanity, including the prevention and treatment of human disease, new agricultural products, industrial innovations, a subfield of computer science, and rapid advances in life sciences. Discoveries in evolutionary biology have made a significant impact not just in the traditional branches of biology but also in other academic disciplines (e.g., biological anthropology and evolutionary psychology) and in society at large.