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  • https://ui.adsabs.harvard.edu/abs/1998Geomo..22..325G
    New constraints on the evolution of Carolina Bays from ground-penetrating radar
    Ground-penetrating radar (GPR) data for the Savannah River Site (SRS) in the Upper Coastal Plain of South Carolina, combined with geological, archaeological, and ecological data place new constraints on the evolution of Carolina Bays. Extant SRS bay morphology formed mainly during the Holocene and did not involve migration of bays across the landscape. Multiple periods of bay-rim accretion with intervening intervals of erosion may characterize the longer-term evolution of the bays. Bay evolution, however, did not involve significant modification of the Upland Unit underlying the region. During fluctuating, but generally open water conditions, breaking waves along bay shorelines eroded and transported sediment which was subsequently exposed for deflation during periods of low water. Deflation and transport of sand into standing vegetation along the margin of the bay depression created a rim in the form of a parabolic dune lacking obvious internal stratification. Simultaneously, infilling occurred by shoreline erosion and transport from adjacent elevated surfaces. This, coupled with growth of emergent vegetation, resulted in decreased hydroperiod, wave energy, shoreline modification, and rim accretion. Transport of some rim sediments back into the bays via alluvial and colluvial activity created wedges of infilling sediment during waning stages of evolution. The apparent contradiction of bay orientation with respect to prevailing winds might reflect seasonal changes in water level and wind direction: southwesterly winds during spring high water causes NW-SE elongation of the bays, whereas northwesterly winds during lower water in the fall and winter account for nearshore deflation and rim accretion along the east-southeastern bay margins.
    UI.ADSABS.HARVARD.EDU
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  • https://arxiv.org/abs/1703.03864
    Evolution Strategies as a Scalable Alternative to Reinforcement Learning
    We explore the use of Evolution Strategies (ES), a class of black box optimization algorithms, as an alternative to popular MDP-based RL techniques such as Q-learning and Policy Gradients. Experiments on MuJoCo and Atari show that ES is a viable solution strategy that scales extremely well with the number of CPUs available: By using a novel communication strategy based on common random numbers, our ES implementation only needs to communicate scalars, making it possible to scale to over a thousand parallel workers. This allows us to solve 3D humanoid walking in 10 minutes and obtain competitive results on most Atari games after one hour of training. In addition, we highlight several advantages of ES as a black box optimization technique: it is invariant to action frequency and delayed rewards, tolerant of extremely long horizons, and does not need temporal discounting or value function approximation.
    ARXIV.ORG
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    https://arxiv.org/abs/1703.03864
    Evolution Strategies as a Scalable Alternative to Reinforcement Learning
    We explore the use of Evolution Strategies (ES), a class of black box optimization algorithms, as an alternative to popular MDP-based RL techniques such as Q-learning and Policy Gradients. Experiments on MuJoCo and Atari show that ES is a viable solution strategy that scales extremely well with the number of CPUs available: By using a novel communication strategy based on common random numbers, our ES implementation only needs to communicate scalars, making it possible to scale to over a thousand parallel workers. This allows us to solve 3D humanoid walking in 10 minutes and obtain competitive results on most Atari games after one hour of training. In addition, we highlight several advantages of ES as a black box optimization technique: it is invariant to action frequency and delayed rewards, tolerant of extremely long horizons, and does not need temporal discounting or value function approximation.
    ARXIV.ORG
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  • https://www.thehealthsite.com/topics/coronavirus-evolution/
    coronavirus evolution : Top and Latest News, Articles, Videos and Photo About coronavirus evolution
    Get coronavirus evolution latest news, Article video and Photos on coronavirus evolution Explore latest health updates, news, information from TheHealthSite.com
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  • https://ui.adsabs.harvard.edu/abs/2004JHumE..47..253G
    Human size evolution: no evolutionary allometric relationship between male and female stature
    In many animal groups, sexual size dimorphism tends to be more pronounced in species with large body size. Similarly, in a previous cross-cultural analysis, male and female stature in humans were shown to be positively allometrically related, indicating a similar relationship where populations with larger stature were more dimorphic. In this study, we re-examine the hypothesis of an allometric relationship between the sexes using phylogenetic methodology. First, however, we tested whether there exist phylogenetic signals in male and female stature. Data on mean stature from 124 human populations was gathered from the literature. A phylogenetic test showed that male and female stature were significantly associated with phylogeny. These results indicate that comparative methods that to some degree incorporate genetic relatedness between populations are crucial when analyzing human size evolution in a cross-cultural context. Further, neither non-phylogenetic nor phylogenetic analyses revealed any allometric relationship between male and female stature. Thus, we found no support for the idea that sexual dimorphism increases with increasing stature in humans.
    UI.ADSABS.HARVARD.EDU
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  • https://ui.adsabs.harvard.edu/abs/2023NatSR..13.6841R
    The aorta in humans and African great apes, and cardiac output and metabolic levels in human evolution
    Humans have a larger energy budget than great apes, allowing the combination of the metabolically expensive traits that define our life history. This budget is ultimately related to the cardiac output, the product of the blood pumped from the ventricle and the number of heart beats per minute, a measure of the blood available for the whole organism physiological activity. To show the relationship between cardiac output and energy expenditure in hominid evolution, we study a surrogate measure of cardiac output, the aortic root diameter, in humans and great apes. When compared to gorillas and chimpanzees, humans present an increased body mass adjusted aortic root diameter. We also use data from the literature to show that over the human lifespan, cardiac output and total energy expenditure follow almost identical trajectories, with a marked increase during the period of brain growth, and a plateau during most of the adult life. The limited variation of adjusted cardiac output with sex, age and physical activity supports the compensation model of energy expenditure in humans. Finally, we present a first study of cardiac output in the skeleton through the study of the aortic impression in the vertebral bodies of the spine. It is absent in great apes, and present in humans and Neanderthals, large-brained hominins with an extended life cycle. An increased adjusted cardiac output, underlying higher total energy expenditure, would have been a key process in human evolution.
    UI.ADSABS.HARVARD.EDU
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  • https://ui.adsabs.harvard.edu/abs/1969PNAS...63.1181K
    The Rate of Molecular Evolution Considered from the Standpoint of Population Genetics
    The rate of amino acid substitutions in the evolution of homologous proteins is remarkably constant. Furthermore, estimated rates of amino acid substitutions based on comparisons of the alpha hemoglobin chains of various mammals with that of the carp are about the same as those based on comparisons of the carp alpha and mammalian beta or the alpha and beta chains in mammals. These uniformities are regarded as evidence for the hypothesis that a majority of amino acid substitutions that occurred in these proteins are the result of random fixation of selectively neutral or nearly neutral mutations. Two implications of this possibility are discussed: (a) Random gene frequency drift is playing an important role in determining the genetic structure of biological populations and (b) genes in "living fossils" may be expected to have undergone as many DNA base (and therefore amino acid) substitutions as corresponding genes (proteins) in more rapidly evolving species.
    UI.ADSABS.HARVARD.EDU
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  • https://ui.adsabs.harvard.edu/abs/2002Natur.415.1024F
    Testing the neutral theory of molecular evolution with genomic data from Drosophila
    Although positive selection has been detected in many genes, its overall contribution to protein evolution is debatable. If the bulk of molecular evolution is neutral, then the ratio of amino-acid (A) to synonymous (S) polymorphism should, on average, equal that of divergence. A comparison of the A/S ratio of polymorphism in Drosophila melanogaster with that of divergence from Drosophila simulans shows that the A/S ratio of divergence is twice as high-a difference that is often attributed to positive selection. But an increase in selective constraint owing to an increase in effective population size could also explain this observation, and, if so, all genes should be affected similarly. Here we show that the difference between polymorphism and divergence is limited to only a fraction of the genes, which are also evolving more rapidly, and this implies that positive selection is responsible. A higher A/S ratio of divergence than of polymorphism is also observed in other species, which suggests a rate of adaptive evolution that is far higher than permitted by the neutral theory of molecular evolution.
    UI.ADSABS.HARVARD.EDU
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  • https://en.wikipedia.org/wiki/Evolution
    Evolution
    Evolution is the change in the heritable characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. The process of evolution has given rise to biodiversity at every level of biological organisation. The scientific theory of evolution by natural selection was conceived independently by two British naturalists, Charles Darwin and Alfred Russel Wallace, in the mid-19th century as an explanation for why organisms are adapted to their physical and biological environments. The theory was first set out in detail in Darwin's book On the Origin of Species. Evolution by natural selection is established by observable facts about living organisms: (1) more offspring are often produced than can possibly survive; (2) traits vary among individuals with respect to their morphology, physiology, and behaviour; (3) different traits...
    EN.WIKIPEDIA.ORG
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  • https://ui.adsabs.harvard.edu/abs/2010Natur.466.1057N
    The evolution of eusociality
    Eusociality, in which some individuals reduce their own lifetime reproductive potential to raise the offspring of others, underlies the most advanced forms of social organization and the ecologically dominant role of social insects and humans. For the past four decades kin selection theory, based on the concept of inclusive fitness, has been the major theoretical attempt to explain the evolution of eusociality. Here we show the limitations of this approach. We argue that standard natural selection theory in the context of precise models of population structure represents a simpler and superior approach, allows the evaluation of multiple competing hypotheses, and provides an exact framework for interpreting empirical observations.
    UI.ADSABS.HARVARD.EDU
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  • ary-algorithm/

    #include <iostream>
    #include <string>
    #include <vector>
    #include <algorithm>
    #include <random>
    #include <chrono>

    using namespace std;

    // random generator function:
    int myrandom (int i) { return std::rand()%i;}


    int main () {

    // seed the random number generator with a constant value:
    srand( unsigned (time(0)) );

    const string target = "Hello World!"; // target string we are trying to match

    const int populationSize = 500; // population size of our genetic algorithm

    vector<string> population; // vector to store our population of strings

    int generation = 0; // current generation number

    // create a random starting population of strings:

    for (int i=0; i<populationSize; i++) {

    string str;

    for (int j=0; j<target.length(); j++) {

    char c = 97 + rand() % 26; // generate a random lowercase character from 'a' to 'z'

    str += c;

    }

    population.push_back(str); // add the generated string to the population vector

    }

    while (true) { // loop until we find the target string

    cout << "Generation: " << generation++ << endl;

    for (int i=0; i<population.size(); i++) { // loop through each member of the population

    cout << "String: " << population[i] << "\t\tFitness: " << fitness(population[i]) << endl;

    if (population[i] == target) { // check if this member is equal to the target string

    cout << "Target Reached!" << endl;
    return 0; // exit program if target is reached

    }
    }

    vector<string> newPopulation;// create a new empty vector for our new generation of strings

    for (int i=0 ; i<population.size(); i++) {// loop through each member of the current population

    string parent1 = selection(population);// select two parents using tournament selection
    string parent2 = selection(population);

    vector<string> children = crossover(parent1, parent2);// perform crossover between parents and generate two children
    mutation(children[0]);// perform mutation on both children mutation(children[1]); newPopulation.push_back(children[0]);// add both children to the new generation's population newPopulation.push_back(children[1]); } population = newPopulation;// replace old generation's population with the new one } return 0;}

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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive. During its life, a star will pass through several stages, fusing lighter elements into heavier ones in successive nuclear reactions. These reactions release energy, which allows the star to radiate light and heat into space. As it ages, a star will move through different stages, including main sequence, red giant, and white dwarf. In some cases, stars may even end their lives as supernovae or neutron stars.

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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star. Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star, but as the preponderance of hydrogen gets used up, more and heavier elements are created by fusion processes in layers around the core. The outflow of energy from the core causes it to gradually expand and cool over time, thereby transforming it into a red giant. Stars with at least half to three-quarters of the mass of our Sun will expand further into a supergiant phase before running out of fuel and collapsing into an incredibly dense white dwarf. Stars with greater than three solar masses will continue to collapse until they become dense enough to begin thermonuclear fusion in their cores; these are known as supernovas. Finally, stars that are even more massive will be able to sustain nuclear fusion in their cores even after they collapse, forming neutron stars or black holes depending on their mass and rotation rate.

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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive. During its life, a star will pass through several stages, such as protostar, main-sequence star, red giant and white dwarf. The more massive stars will also go through supernova and neutron star stages. As it ages, a star's temperature and luminosity will change, and it may also undergo pulsations and mass loss.

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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive. During its life, a star will pass through several stages, such as a protostar, main-sequence star, red giant and white dwarf. During each stage, different nuclear reactions take place in the core of the star, causing it to heat up or cool down and change in luminosity and size. Eventually, all stars will end their lives by either exploding as supernovae or collapsing into black holes.

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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive. During its life, a star will pass through various stages, such as protostar, main-sequence star, red giant, and white dwarf. The energy produced by stars comes from nuclear fusion reactions in which hydrogen is converted into helium. As a star ages, it will eventually exhaust its supply of hydrogen fuel and move on to other elements in its core. This process leads to changes in stellar structure and luminosity as well as the eventual death of the star.

    By: ChatGPT AI
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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive. During its life, a star will pass through various stages, such as a protostar, main-sequence star, red giant, and white dwarf. Each stage is characterized by different properties such as luminosity and temperature. As a star ages, it will also undergo nuclear fusion reactions in its core that produce heavier elements from lighter ones. These heavier elements are then released into space when the star dies, enriching the interstellar medium with new material.

    By: ChatGPT AI
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  • Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive. During its life, a star will pass through several stages, such as a protostar, main-sequence star, red giant, and white dwarf. As it evolves, a star will undergo nuclear fusion in its core and produce energy in the form of radiation. This radiation will cause the star to expand and contract in size as it moves through different stages of its life cycle.

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  • -of-the-web

    The evolution of the web began in 1989 when Tim Berners-Lee proposed the idea of a global hypertext project. This was the first step towards creating the World Wide Web. In 1991, Berners-Lee and his team at CERN released the first web browser, which allowed users to navigate through documents that were linked together via hypertext. This was the beginning of what we know today as the internet.

    In 1993, Marc Andreessen released Mosaic, which was the first graphical web browser and allowed users to view images and videos on websites. This was a major breakthrough in web technology and led to a surge in internet usage.

    The late 1990s saw a number of important developments in web technology. Netscape Navigator became one of the most popular browsers and HTML 4 was released, which introduced new features such as tables and frames. Java applets also became popular during this time, allowing developers to create interactive websites with dynamic content.

    In 2000, Microsoft released Internet Explorer 6, which became one of the most widely used browsers for many years afterwards. The same year also saw the release of XML, which allowed developers to structure data more effectively than HTML.

    The early 2000s saw a number of important developments in web technology including AJAX (Asynchronous JavaScript And XML), which allowed for faster loading times on websites; CSS (Cascading Style Sheets), which allowed developers to separate content from design; and RSS (Really Simple Syndication), which made it easier for users to keep up with their favorite websites.

    The mid-2000s saw an explosion in social media usage with sites such as Myspace and Facebook becoming hugely popular amongst internet users. This period also saw an increase in mobile device usage with smartphones becoming commonplace by 2010. In response to this trend, responsive design techniques were developed that allowed websites to adapt their layout depending on the device they were being viewed on.

    Today, web technology is constantly evolving with new technologies such as HTML5 being developed all the time. Web development is now much more complex than it was when it first began but it has come a long way since 1989 when Tim Berners-Lee proposed his idea for a global hypertext project!

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  • The first known use of the word "evolution" in English was in 1679, when it was used by Thomas Browne in his book Religio Medici. The term had been used earlier by French philosopher and mathematician René Descartes (1596-1650) and German naturalist and physician Georges-Louis Leclerc, Comte de Buffon (1707-1788). In the 19th century, Charles Darwin popularized the concept of evolution through his work On the Origin of Species. Since then, evolutionary theory has been widely accepted as a scientific explanation for the diversity of life on Earth. Evolutionary biology is now a major field of study, with researchers exploring topics such as genetic drift, natural selection, speciation, and adaptation.

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  • Tom Hanks Evolution
    Tom Hanks Evolution 1980-2022 #Shorts.
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  • A new supercomputer simulation animates the evolution of the universe
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  • The Insane Evolution of the Woolly Rhino
    Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.
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