The Academy's Evolution Site<br /><br />Biological evolution is one of the most important concepts in biology. The Academies are involved in helping those who are interested in science comprehend the evolution theory and how it can be applied across all areas of scientific research.<br /><br />This site offers a variety of sources for teachers, students as well as general readers about evolution. It includes key video clip from NOVA and WGBH produced science programs on DVD.<br /><br />Tree of Life<br /><br />The Tree of Life, an ancient symbol, represents the interconnectedness of all life. It is used in many spiritual traditions and cultures as a symbol of unity and love. It also has important practical applications, such as providing a framework to understand the evolution of species and how they react to changes in the environment.<br /><br />The first attempts to depict the world of biology were built on categorizing organisms based on their metabolic and physical characteristics. These methods, which are based on the collection of various parts of organisms or short DNA fragments have greatly increased the diversity of a tree of Life2. However, these trees are largely comprised of eukaryotes, and bacterial diversity is still largely unrepresented3,4.<br /><br /><br /><br />By avoiding the need for direct experimentation and observation genetic techniques have made it possible to depict the Tree of Life in a much more accurate way. We can construct trees using molecular techniques like the small-subunit ribosomal gene.<br /><br />The Tree of Life has been significantly expanded by genome sequencing. However, there is still much biodiversity to be discovered. This is particularly the case for microorganisms which are difficult to cultivate and are typically present in a single sample5. A recent analysis of all known genomes has produced a rough draft version of the Tree of Life, including numerous bacteria and archaea that are not isolated and their diversity is not fully understood6.<br /><br />This expanded Tree of Life can be used to assess the biodiversity of a particular area and determine if certain habitats need special protection. This information can be used in a range of ways, from identifying new treatments to fight disease to enhancing the quality of the quality of crops. This information is also useful in conservation efforts. It can help biologists identify the areas most likely to contain cryptic species with important metabolic functions that could be at risk of anthropogenic changes. Although funds to protect biodiversity are essential however, the most effective method to protect the world's biodiversity is for more people in developing countries to be empowered with the necessary knowledge to act locally to promote conservation from within.<br /><br />Phylogeny<br /><br />A phylogeny (also known as an evolutionary tree) depicts the relationships between species. Using molecular data similarities and differences in morphology, or ontogeny (the process of the development of an organism) scientists can construct a phylogenetic tree that illustrates the evolutionary relationship between taxonomic groups. The phylogeny of a tree plays an important role in understanding biodiversity, genetics and evolution.<br /><br />A basic phylogenetic tree (see Figure PageIndex 10 Identifies the relationships between organisms that have similar traits and have evolved from an ancestor with common traits. These shared traits can be either analogous or homologous. <a href="https://evolutionkr.kr/">무료에볼루션</a> are the same in terms of their evolutionary journey. Analogous traits might appear similar, but they do not have the same origins. Scientists put similar traits into a grouping known as a Clade. Every organism in a group have a common characteristic, for example, amniotic egg production. They all came from an ancestor who had these eggs. The clades are then connected to form a phylogenetic branch to determine the organisms with the closest relationship to.<br /><br />For a more precise and accurate phylogenetic tree, scientists rely on molecular information from DNA or RNA to determine the relationships among organisms. This information is more precise and provides evidence of the evolution of an organism. The use of molecular data lets researchers determine the number of species that have the same ancestor and estimate their evolutionary age.<br /><br />The phylogenetic relationships between species can be influenced by several factors, including phenotypic plasticity an aspect of behavior that alters in response to unique environmental conditions. This can cause a particular trait to appear more like a species other species, which can obscure the phylogenetic signal. This problem can be addressed by using cladistics, which is a a combination of analogous and homologous features in the tree.<br /><br />In addition, phylogenetics can help predict the time and pace of speciation. This information will assist conservation biologists in deciding which species to safeguard from disappearance. In the end, it's the preservation of phylogenetic diversity that will lead to an ecologically balanced and complete ecosystem.<br /><br />Evolutionary Theory<br /><br />The main idea behind evolution is that organisms alter over time because of their interactions with their environment. Several theories of evolutionary change have been developed by a variety of scientists including the Islamic naturalist Nasir al-Din al-Tusi (1201-1274) who envisioned an organism developing gradually according to its needs, the Swedish botanist Carolus Linnaeus (1707-1778) who developed modern hierarchical taxonomy, and Jean-Baptiste Lamarck (1744-1829) who suggested that the use or misuse of traits causes changes that can be passed on to the offspring.<br /><br />In the 1930s and 1940s, theories from various fields, including genetics, natural selection, and particulate inheritance - came together to form the modern evolutionary theory synthesis which explains how evolution occurs through the variation of genes within a population and how these variants change in time as a result of natural selection. This model, known as genetic drift mutation, gene flow, and sexual selection, is a key element of modern evolutionary biology and can be mathematically described.<br /><br />Recent discoveries in the field of evolutionary developmental biology have demonstrated that genetic variation can be introduced into a species by mutation, genetic drift, and reshuffling of genes during sexual reproduction, and also through the movement of populations. These processes, as well as others like directional selection and genetic erosion (changes in the frequency of the genotype over time), can lead to evolution which is defined by change in the genome of the species over time, and also the change in phenotype as time passes (the expression of that genotype in an individual).<br /><br />Incorporating evolutionary thinking into all areas of biology education could increase students' understanding of phylogeny and evolutionary. A recent study by Grunspan and colleagues, for instance, showed that teaching about the evidence supporting evolution increased students' understanding of evolution in a college-level biology class. To find out more about how to teach about evolution, please see The Evolutionary Potential in All Areas of Biology and Thinking Evolutionarily: A Framework for Infusing the Concept of Evolution into Life Sciences Education.<br /><br />Evolution in Action<br /><br />Scientists have traditionally looked at evolution through the past, analyzing fossils and comparing species. They also observe living organisms. Evolution isn't a flims event; it is an ongoing process that continues to be observed today. Viruses reinvent themselves to avoid new antibiotics and bacteria transform to resist antibiotics. Animals adapt their behavior as a result of a changing world. The changes that result are often visible.<br /><br />But it wasn't until the late 1980s that biologists realized that natural selection could be observed in action as well. The key to this is that different traits result in the ability to survive at different rates and reproduction, and they can be passed down from generation to generation.<br /><br />In the past, when one particular allele--the genetic sequence that determines coloration--appeared in a population of interbreeding organisms, it might rapidly become more common than the other alleles. As time passes, that could mean that the number of black moths within the population could increase. The same is true for many other characteristics--including morphology and behavior--that vary among populations of organisms.<br /><br />It is easier to see evolutionary change when a species, such as bacteria, has a high generation turnover. Since 1988, Richard Lenski, a biologist, has studied twelve populations of E.coli that descend from one strain. The samples of each population have been taken frequently and more than 500.000 generations of E.coli have been observed to have passed.<br /><br />Lenski's work has shown that mutations can alter the rate of change and the rate at which a population reproduces. It also shows evolution takes time, which is difficult for some to accept.<br /><br />Microevolution can be observed in the fact that mosquito genes for 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 selective pressure that favors those with resistant genotypes.<br /><br />The rapidity of evolution has led to an increasing appreciation of its importance, especially in a world shaped largely by human activity. This includes climate change, pollution, and habitat loss, which prevents many species from adapting. Understanding evolution can help you make better decisions about the future of our planet and its inhabitants.<br /><br />