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The Academy's Evolution Site The concept of biological evolution is a fundamental concept in biology. The Academies have been active for a long time in helping those interested in science comprehend the concept of evolution and how it permeates all areas of scientific research. This site provides students, teachers and general readers with a range of learning resources on evolution. It also includes important video clips from NOVA and WGBH produced science programs on DVD. Tree of Life The Tree of Life, an ancient symbol, symbolizes the interconnectedness of all life. 에볼루션사이트 is a symbol of love and harmony in a variety of cultures. It has many practical applications as well, such as providing a framework to understand the history of species and how they react to changes in environmental conditions. Early approaches to depicting the biological world focused on the classification of organisms into distinct categories that had been distinguished by physical and metabolic characteristics1. These methods, which rely on the collection of various parts of organisms, or fragments of DNA, have greatly increased the diversity of a Tree of Life2. These trees are largely composed of eukaryotes, while bacteria are largely underrepresented3,4. In avoiding the necessity of direct experimentation and observation genetic techniques have enabled us to depict the Tree of Life in a much more accurate way. Trees can be constructed by using molecular methods like the small-subunit ribosomal gene. The Tree of Life has been dramatically expanded through genome sequencing. However, there is still much biodiversity to be discovered. This is especially true of microorganisms, which are difficult to cultivate and are typically only present in a single specimen5. Recent analysis of all genomes resulted in a rough draft of a Tree of Life. This includes a variety of bacteria, archaea and other organisms that haven't yet been isolated, or their diversity is not fully understood6. This expanded Tree of Life can be used to determine the diversity of a specific region and determine if certain habitats require special protection. This information can be utilized in many ways, including finding new drugs, battling diseases and improving the quality of crops. The information is also incredibly valuable in conservation efforts. It helps biologists discover areas that are likely to have species that are cryptic, which could perform important metabolic functions and be vulnerable to changes caused by humans. Although funds to safeguard biodiversity are vital but the most effective way to protect the world's biodiversity is for more people in developing countries to be empowered with the knowledge to act locally in order to promote conservation from within. Phylogeny A phylogeny (also called an evolutionary tree) illustrates the relationship between different organisms. Scientists can construct an phylogenetic chart which shows the evolutionary relationships between taxonomic groups using molecular data and morphological similarities or differences. The phylogeny of a tree plays an important role in understanding biodiversity, genetics and evolution. A basic phylogenetic tree (see Figure PageIndex 10 ) is a method of identifying the relationships between organisms with similar traits that evolved from common ancestral. These shared traits can be either homologous or analogous. Homologous characteristics are identical in their evolutionary path. Analogous traits might appear like they are but they don't share the same origins. Scientists organize similar traits into a grouping known as a Clade. For example, all of the organisms in a clade share the trait of having amniotic eggs. They evolved from a common ancestor which had eggs. The clades are then linked to form a phylogenetic branch to identify organisms that have the closest relationship to. Scientists make use of molecular DNA or RNA data to build a phylogenetic chart which is more precise and detailed. This data is more precise than morphological information and provides evidence of the evolutionary history of an individual or group. Researchers can use Molecular Data to determine the evolutionary age of organisms and determine the number of organisms that share the same ancestor. The phylogenetic relationships between organisms can be influenced by several factors including phenotypic plasticity, a kind of behavior that changes in response to specific environmental conditions. This can cause a trait to appear more similar in one species than another, obscuring the phylogenetic signal. However, this problem can be solved through the use of methods such as cladistics which combine homologous and analogous features into the tree. Additionally, phylogenetics aids predict the duration and rate at which speciation takes place. This information can aid conservation biologists to make decisions about which species to protect from extinction. Ultimately, it is the preservation of phylogenetic diversity which will result in an ecologically balanced and complete ecosystem. Evolutionary Theory The main idea behind evolution is that organisms alter over time because of their interactions with their environment. Many scientists have developed theories of evolution, including the Islamic naturalist Nasir al-Din al-Tusi (1201-274) who believed that an organism would evolve according to its own requirements as well as the Swedish taxonomist Carolus Linnaeus (1707-1778) who conceived the modern hierarchical taxonomy as well as Jean-Baptiste Lamarck (1844-1829), who believed that the usage or non-use of certain traits can result in changes that are passed on to the In the 1930s and 1940s, theories from a variety of fields — including genetics, natural selection and particulate inheritance—came together to form the current synthesis of evolutionary theory, which defines how evolution happens through the variation of genes within a population, and how those variants change in time as a result of natural selection. This model, which incorporates mutations, genetic drift, gene flow and sexual selection is mathematically described mathematically. Recent discoveries in evolutionary developmental biology have shown the ways in which variation can be introduced to a species via mutations, genetic drift or reshuffling of genes in sexual reproduction, and even migration between populations. These processes, along with others such as directional selection and gene erosion (changes in the frequency of genotypes over time) can lead to evolution. Evolution is defined as changes in the genome over time and changes in phenotype (the expression of genotypes in individuals). Incorporating evolutionary thinking into all areas of biology education can increase students' understanding of phylogeny and evolutionary. A recent study conducted by Grunspan and colleagues, for instance demonstrated that teaching about the evidence supporting evolution helped students accept the concept of evolution in a college-level biology class. For 에볼루션바카라 about how to teach evolution look up The Evolutionary Potential in all Areas of Biology or Thinking Evolutionarily A Framework for Integrating Evolution into Life Sciences Education. Evolution in Action Traditionally, scientists have studied evolution through looking back, studying fossils, comparing species and studying living organisms. But evolution isn't just something that happened in the past; it's an ongoing process happening right now. Bacteria mutate and resist antibiotics, viruses reinvent themselves and escape new drugs and animals change their behavior to a changing planet. The changes that result are often evident. It wasn't until the 1980s when biologists began to realize that natural selection was also in action. The main reason is that different traits can confer an individual rate of survival as well as reproduction, and may be passed down from generation to generation. In the past when one particular allele—the genetic sequence that defines color in a population of interbreeding species, it could quickly become more common than other alleles. Over time, this would mean that the number of moths that have black pigmentation in a population may increase. The same is true for many other characteristics—including morphology and behavior—that vary among populations of organisms. Monitoring evolutionary changes in action is easier when a species has a rapid generation turnover, as with bacteria. Since 1988 the biologist Richard Lenski has been tracking twelve populations of E. Coli that descended from a single strain; samples of each are taken regularly and more than 50,000 generations have now been observed. Lenski's work has shown that mutations can alter the rate of change and the effectiveness of a population's reproduction. It also shows that evolution takes time, a fact that is hard for some to accept. Another example of microevolution is how mosquito genes that are resistant to pesticides show up more often in populations where insecticides are employed. This is because the use of pesticides creates a pressure that favors those with resistant genotypes. The speed at which evolution takes place has led to a growing recognition of its importance in a world shaped by human activities, including climate change, pollution, and the loss of habitats that hinder many species from adjusting. Understanding evolution can aid you in making better decisions about the future of the planet and its inhabitants.