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The Importance of Understanding Evolution The majority of evidence for evolution comes from observation of organisms in their natural environment. Scientists use lab experiments to test their the theories of evolution. In time, the frequency of positive changes, like those that aid individuals in their struggle to survive, increases. This process is called natural selection. Natural Selection The theory of natural selection is a key element to evolutionary biology, however it is also a key aspect of science education. Numerous studies have shown that the concept of natural selection as well as its implications are largely unappreciated by many people, including those who have postsecondary biology education. A basic understanding of the theory however, is essential for both academic and practical contexts such as research in the field of medicine or management of natural resources. The easiest method to comprehend the idea of natural selection is as a process that favors helpful characteristics and makes them more prevalent in a population, thereby increasing their fitness. The fitness value is a function the relative contribution of the gene pool to offspring in every generation. Despite its popularity however, this theory isn't without its critics. They argue that it's implausible that beneficial mutations are constantly more prevalent in the gene pool. Additionally, they argue that other factors, such as random genetic drift or environmental pressures could make it difficult for beneficial mutations to gain a foothold in a population. These critiques usually are based on the belief that the concept of natural selection is a circular argument. A favorable trait must exist before it can benefit the population, and a favorable trait can be maintained in the population only if it benefits the population. Critics of this view claim that the theory of the natural selection isn't a scientific argument, but merely an assertion of evolution. A more thorough criticism of the theory of evolution is centered on the ability of it to explain the development adaptive features. These are also known as adaptive alleles. They are defined as those that increase the chances of reproduction in the face of competing alleles. The theory of adaptive alleles is based on the idea that natural selection can create these alleles by combining three elements: The first is a phenomenon called genetic drift. This happens when random changes occur in the genetics of a population. This could result in a booming or shrinking population, depending on the amount of variation that is in the genes. The second element is a process called competitive exclusion. It describes the tendency of certain alleles to disappear from a population due competition with other alleles for resources, such as food or friends. Genetic Modification Genetic modification is a range of biotechnological procedures that alter the DNA of an organism. This can lead to many benefits, including greater resistance to pests as well as increased nutritional content in crops. It is also used to create therapeutics and gene therapies that treat genetic causes of disease. Genetic Modification can be used to tackle many of the most pressing issues in the world, such as climate change and hunger. Traditionally, scientists have utilized model organisms such as mice, flies and worms to determine the function of certain genes. This method is hampered by the fact that the genomes of the organisms cannot be modified to mimic natural evolutionary processes. Using gene editing tools like CRISPR-Cas9, researchers are now able to directly alter the DNA of an organism to produce a desired outcome. This is referred to as directed evolution. Essentially, scientists identify the target gene they wish to alter and then use an editing tool to make the needed change. Then they insert the modified gene into the organism, and hopefully it will pass to the next generation. A new gene that is inserted into an organism may cause unwanted evolutionary changes, which can undermine the original intention of the alteration. Transgenes inserted into DNA of an organism may affect its fitness and could eventually be removed by natural selection. Another issue is making sure that the desired genetic change spreads to all of an organism's cells. This is a major challenge since each cell type is different. Cells that comprise an organ are very different from those that create reproductive tissues. To effect a major change, it is important to target all of the cells that must be altered. These issues have led some to question the ethics of the technology. Some believe that altering DNA is morally wrong and like playing God. Other people are concerned that Genetic Modification will lead to unexpected consequences that could negatively affect the environment and human health. Adaptation Adaptation happens when an organism's genetic characteristics are altered to adapt to the environment. These changes are usually a result of natural selection over many generations, but can also occur due to random mutations that cause certain genes to become more prevalent in a group of. The effects of adaptations can be beneficial to an individual or a species, and can help them to survive in their environment. The finch-shaped beaks on the Galapagos Islands, and thick fur on polar bears are instances of adaptations. In certain cases two species can evolve to be dependent on one another in order to survive. For example orchids have evolved to resemble the appearance and smell of bees in order to attract them to pollinate. An important factor in free evolution is the role played by competition. The ecological response to an environmental change is significantly less when competing species are present. This is because interspecific competition has asymmetrically impacted the size of populations and fitness gradients. This influences how evolutionary responses develop after an environmental change. look at here of the competition and resource landscapes can also have a significant impact on the adaptive dynamics. For instance, a flat or clearly bimodal shape of the fitness landscape increases the likelihood of character displacement. A lack of resource availability could also increase the probability of interspecific competition, by decreasing the equilibrium population sizes for different types of phenotypes. In simulations using different values for the variables k, m v and n I found that the maximum adaptive rates of the species that is disfavored in the two-species alliance are considerably slower than those of a single species. This is due to the favored species exerts direct and indirect competitive pressure on the species that is disfavored which reduces its population size and causes it to fall behind the moving maximum (see the figure. 3F). The impact of competing species on adaptive rates also gets more significant when the u-value is close to zero. The species that is favored can attain its fitness peak faster than the less preferred one even when the value of the u-value is high. The favored species will therefore be able to take advantage of the environment more rapidly than the less preferred one and the gap between their evolutionary rates will grow. Evolutionary Theory As one of the most widely accepted scientific theories, evolution is a key aspect of how biologists examine living things. It is based on the belief that all living species evolved from a common ancestor via natural selection. According to BioMed Central, this is an event where a gene or trait which allows an organism better endure and reproduce within its environment is more prevalent in the population. The more frequently a genetic trait is passed on the more prevalent it will increase and eventually lead to the formation of a new species. The theory also explains how certain traits become more common in the population through a phenomenon known as “survival of the best.” Basically, those with genetic traits that give them an advantage over their rivals have a better chance of surviving and producing offspring. The offspring of these organisms will inherit the advantageous genes, and over time the population will evolve. In the years following Darwin's death a group led by the Theodosius dobzhansky (the grandson of Thomas Huxley's bulldog), Ernst Mayr, and George Gaylord Simpson extended Darwin's ideas. This group of biologists who were referred to as the Modern Synthesis, produced an evolutionary model that was taught to millions of students in the 1940s & 1950s. However, this evolutionary model is not able to answer many of the most important questions regarding evolution. It does not provide an explanation for, for instance the reason that some species appear to be unchanged while others undergo rapid changes in a short time. It also doesn't address the problem of entropy, which says that all open systems tend to break down in time. A increasing number of scientists are challenging the Modern Synthesis, claiming that it isn't able to fully explain evolution. In the wake of this, various alternative models of evolution are being proposed. This includes the notion that evolution, instead of being a random and predictable process, is driven by “the necessity to adapt” to the ever-changing environment. They also consider the possibility of soft mechanisms of heredity that do not depend on DNA.