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The Academy's Evolution Site The concept of biological evolution is among the most important concepts in biology. The Academies are involved in helping those interested in science to learn about the theory of evolution and how it is permeated across all areas of scientific research. This site provides teachers, students and general readers with a variety of learning resources on evolution. It has important video clips from NOVA and WGBH-produced science programs on DVD. Tree of Life The Tree of Life is an ancient symbol that symbolizes the interconnectedness of all life. It is seen in a variety of spiritual traditions and cultures as a symbol of unity and love. It can be used in many practical ways as well, including providing a framework to understand the evolution of species and how they respond to changes in environmental conditions. Early attempts to represent the biological world were founded on categorizing organisms on their physical and metabolic characteristics. These methods, which relied on the sampling of various parts of living organisms or on short fragments of their DNA, significantly increased the variety that could be represented in a tree of life2. However, these trees are largely composed of eukaryotes; bacterial diversity is still largely unrepresented3,4. Genetic techniques have greatly broadened our ability to depict the Tree of Life by circumventing the requirement for direct observation and experimentation. We can create trees by using molecular methods like the small-subunit ribosomal gene. The Tree of Life has been greatly expanded thanks to genome sequencing. However there is still a lot of biodiversity to be discovered. This is especially true of microorganisms, which can be difficult to cultivate and are often only present in a single sample5. A recent study of all genomes known to date has produced a rough draft version of the Tree of Life, including numerous archaea and bacteria that have not been isolated and which are not well understood. 에볼루션 슬롯게임 expanded Tree of Life is particularly useful for assessing the biodiversity of an area, helping to determine whether specific habitats require special protection. This information can be utilized in a variety of ways, from identifying the most effective medicines to combating disease to enhancing crops. This information is also extremely useful to conservation efforts. It helps biologists determine those areas that are most likely contain cryptic species that could have important metabolic functions that could be at risk of anthropogenic changes. While funds to safeguard biodiversity are vital, ultimately the best way to protect the world's biodiversity is for more people living in developing countries to be equipped with the knowledge to take action locally to encourage conservation from within. Phylogeny A phylogeny, also called an evolutionary tree, reveals the relationships between groups of organisms. Scientists can build an phylogenetic chart which shows the evolutionary relationships between taxonomic groups based on molecular data and morphological differences or similarities. 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 that share similar traits that evolved from common ancestral. These shared traits could be homologous, or analogous. Homologous traits share their underlying evolutionary path while analogous traits appear similar but do not have the identical origins. Scientists combine similar traits into a grouping called a Clade. All members of a clade share a trait, such as amniotic egg production. They all derived from an ancestor with these eggs. The clades then join to form a phylogenetic branch that can identify organisms that have the closest relationship. For a more detailed and accurate phylogenetic tree, scientists use molecular data from DNA or RNA to establish the relationships between organisms. This information is more precise and provides evidence of the evolution history of an organism. Researchers can utilize Molecular Data to calculate the evolutionary age of organisms and determine the number of organisms that have a common ancestor. The phylogenetic relationships of organisms are influenced by many factors, including phenotypic plasticity a kind of behavior that changes in response to specific environmental conditions. This can make a trait appear more similar to a species than another and obscure the phylogenetic signals. However, this problem can be reduced by the use of methods like cladistics, which incorporate a combination of analogous and homologous features into the tree. Furthermore, phylogenetics may help predict the time and pace of speciation. This information can assist conservation biologists make decisions about the species they should 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 fundamental concept in evolution is that organisms alter over time because of their interactions with their environment. Many theories of evolution have been proposed by a variety of scientists, including the Islamic naturalist Nasir al-Din al-Tusi (1201-1274) who proposed that a living organism develop slowly in accordance with its requirements as well as the Swedish botanist Carolus Linnaeus (1707-1778) who conceived modern hierarchical taxonomy, and Jean-Baptiste Lamarck (1744-1829) who suggested that the use or non-use of traits cause changes that could be passed onto offspring. In the 1930s and 1940s, theories from a variety of fields—including genetics, natural selection, and particulate inheritance—came together to form the modern synthesis of evolutionary theory, which defines how evolution occurs through the variations of genes within a population and how those variants change over time due to natural selection. This model, called genetic drift or mutation, gene flow, and sexual selection, is the foundation of current evolutionary biology, and is mathematically described. Recent developments in evolutionary developmental biology have demonstrated how variations can be introduced to a species via mutations, genetic drift, reshuffling genes during sexual reproduction and migration between populations. These processes, along with other ones like directional selection and genetic erosion (changes in the frequency of an individual's 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 over time (the expression of that genotype within the individual). Students can gain a better understanding of phylogeny by incorporating evolutionary thinking throughout all areas of biology. In a recent study conducted by Grunspan and co., it was shown that teaching students about the evidence for evolution increased their understanding of evolution in an undergraduate biology course. For more information on how to teach about evolution, see The Evolutionary Potential in all Areas of Biology or Thinking Evolutionarily A Framework for Infusing Evolution into Life Sciences Education. Evolution in Action Traditionally, scientists have studied evolution by looking back—analyzing fossils, comparing species and studying living organisms. Evolution is not a distant moment; it is an ongoing process. Bacteria transform and resist antibiotics, viruses reinvent themselves and are able to evade new medications and animals change their behavior to a changing planet. The resulting changes are often visible. It wasn't until late 1980s that biologists began realize that natural selection was at work. The reason is that different characteristics result in different rates of survival and reproduction (differential fitness), and can be passed down from one generation to the next. In the past, if a certain allele – the genetic sequence that determines colour – was present in a population of organisms that interbred, it could be more common than any other allele. As time passes, this could mean that the number of moths sporting 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 turnover of its generation such as bacteria. Since 1988, Richard Lenski, a biologist, has been tracking twelve populations of E.coli that descend from a single strain. Samples from each population have been taken regularly and more than 500.000 generations of E.coli have been observed to have passed. Lenski's research has revealed that a mutation can profoundly alter the speed at which a population reproduces—and so the rate at which it alters. It also shows evolution takes time, which is difficult for some to accept. 에볼루션 무료 바카라 can be observed in the fact that mosquito genes that confer resistance to pesticides are more prevalent in areas where insecticides have been used. Pesticides create an enticement that favors individuals who have resistant genotypes. The rapidity of evolution has led to an increasing awareness of its significance, especially in a world shaped largely by human activity. This includes pollution, climate change, and habitat loss that hinders many species from adapting. Understanding the evolution process can help you make better decisions about the future of our planet and its inhabitants.