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The Academy's Evolution Site Biology is one of the most important concepts in biology. The Academies have been active for a long time in helping people who are interested in science comprehend the theory of evolution and how it permeates all areas of scientific exploration. This site provides a range of tools for students, teachers, and general readers on evolution. It has the most important video clips from NOVA and WGBH's science programs on DVD. Tree of Life The Tree of Life is an ancient symbol of the interconnectedness of life. It is used in many religions and cultures as a symbol of unity and love. It also has practical applications, such as providing a framework to understand the history of species and how they respond to changing environmental conditions. Early approaches to depicting the world of biology focused on separating organisms into distinct categories which had been distinguished by physical and metabolic characteristics1. These methods, which depend on the collection of various parts of organisms or short fragments of DNA, have significantly increased the diversity of a tree of Life2. However, these trees are largely composed of eukaryotes; bacterial diversity is still largely unrepresented3,4. Genetic techniques have significantly expanded our ability to represent the Tree of Life by circumventing the requirement for direct observation and experimentation. We can construct trees using molecular techniques such as the small subunit ribosomal gene. The Tree of Life has been greatly expanded thanks to genome sequencing. However there is a lot of biodiversity to be discovered. This is particularly the case for microorganisms which are difficult to cultivate, and which are usually only found in a single specimen5. Recent analysis of all genomes resulted in a rough draft of a Tree of Life. This includes a wide range of archaea, bacteria and other organisms that haven't yet been identified or the diversity of which is not fully understood6. The expanded Tree of Life is particularly useful for assessing the biodiversity of an area, which can help to determine if certain habitats require special protection. This Internet site can be used in a variety of ways, from identifying new medicines to combating disease to improving crop yields. The information is also incredibly valuable in conservation efforts. It can aid biologists in identifying areas that are likely to have cryptic species, which may have important metabolic functions and are susceptible to the effects of human activity. Although funding to protect biodiversity are crucial, ultimately the best way to protect the world's biodiversity is for more people in developing countries to be empowered with the necessary knowledge to act locally in order to promote conservation from within. Phylogeny A phylogeny is also known as an evolutionary tree, reveals the connections between groups of organisms. Scientists can build a phylogenetic chart that shows the evolutionary relationship of taxonomic groups using molecular data and morphological similarities or differences. Phylogeny plays a crucial role in understanding the relationship between genetics, biodiversity and evolution. A basic phylogenetic Tree (see Figure PageIndex 10 Determines the relationship between organisms that have similar characteristics and have evolved from an ancestor that shared traits. These shared traits may be analogous, or homologous. Homologous traits are similar in their evolutionary origins and analogous traits appear similar but do not have the identical origins. Scientists group similar traits together into a grouping referred to as a clade. Every organism in a group share a characteristic, like amniotic egg production. They all derived from an ancestor with these eggs. A phylogenetic tree is then constructed by connecting clades to identify the organisms that are most closely related to each other. Scientists utilize molecular DNA or RNA data to construct a phylogenetic graph that is more precise and detailed. This data is more precise than the morphological data and provides evidence of the evolution history of an individual or group. Researchers can use Molecular Data to calculate the evolutionary age of organisms and determine how many organisms have an ancestor common to all. The phylogenetic relationships of organisms are influenced by many factors, including phenotypic plasticity a kind of behavior that alters in response to specific environmental conditions. This can cause a particular trait to appear more like a species another, obscuring the phylogenetic signal. This issue can be cured by using cladistics. This is a method that incorporates the combination of homologous and analogous features in the tree. In addition, phylogenetics can aid in predicting the time and pace of speciation. This information can assist conservation biologists in deciding which species to safeguard from extinction. In the end, it's the conservation of phylogenetic diversity which will create an ecosystem that is balanced and complete. Evolutionary Theory The central theme of evolution is that organisms acquire different features over time due to their interactions with their environment. Many scientists have come up with theories of evolution, such as the Islamic naturalist Nasir al-Din al-Tusi (1201-274) who believed that an organism could evolve according to its individual needs, the Swedish taxonomist Carolus Linnaeus (1707-1778), who created the modern taxonomy system that is hierarchical, as well as Jean-Baptiste Lamarck (1844-1829), who suggested that the use or non-use of traits can cause changes that are passed on to the next generation. In the 1930s and 1940s, concepts from a variety of fields—including natural selection, genetics, and particulate inheritance—came together to create the modern synthesis of evolutionary theory that explains how evolution occurs through the variation of genes within a population and how those variations change in time as a result of natural selection. This model, which incorporates genetic drift, mutations, gene flow and sexual selection is mathematically described mathematically. Recent developments in the field of evolutionary developmental biology have shown that variations can be introduced into a species via mutation, genetic drift, and reshuffling of genes in sexual reproduction, as well as by migration between populations. These processes, as well as others like directional selection and genetic erosion (changes in the frequency of a genotype over time) can lead to evolution which is defined by changes in the genome of the species over time, and also the change in phenotype as time passes (the expression of that genotype within the individual). Incorporating evolutionary thinking into all areas of biology education can improve student understanding of the concepts of phylogeny as well as evolution. A recent study by Grunspan and colleagues, for instance revealed that teaching students about the evidence for evolution increased students' understanding of evolution in a college biology course. To learn more about how to teach about evolution, please read The Evolutionary Potential of All Areas of Biology and Thinking Evolutionarily: A Framework for Infusing Evolution into Life Sciences Education. Evolution in Action Traditionally, scientists have studied evolution by looking back, studying fossils, comparing species, and observing living organisms. However, evolution isn't something that occurred in the past; it's an ongoing process that is taking place in the present. Bacteria mutate and resist antibiotics, viruses evolve and escape new drugs, and animals adapt their behavior to the changing climate. The results are often apparent. However, it wasn't until late 1980s that biologists realized that natural selection can be observed in action as well. The reason is that different traits have different rates of survival and reproduction (differential fitness) and can be passed down from one generation to the next. In 에볼루션 바카라 무료체험 , if one allele – the genetic sequence that determines colour – appeared in a population of organisms that interbred, it could be more common than other allele. As time passes, this could mean that the number of moths sporting black pigmentation in a group may increase. The same is true for many other characteristics—including morphology and behavior—that vary among populations of organisms. It is easier to observe evolutionary change when a species, such as bacteria, has a high generation turnover. Since 1988, biologist Richard Lenski has been tracking twelve populations of E. Coli that descended from a single strain. samples from each population are taken regularly and over fifty thousand generations have been observed. Lenski's research has revealed that mutations can alter the rate of change and the effectiveness at which a population reproduces. It also shows that evolution takes time—a fact that some are unable to accept. Microevolution can be observed in the fact that mosquito genes that confer resistance to pesticides are more prevalent in populations where insecticides have been used. This is due to the fact that the use of pesticides creates a pressure that favors those with resistant genotypes. The speed at which evolution can take place has led to a growing appreciation of its importance in a world that is shaped by human activity—including climate change, pollution, and the loss of habitats that prevent the species from adapting. Understanding the evolution process will assist you in making better choices about the future of our planet and its inhabitants.