What is Free Evolution?<br /><br />Free evolution is the notion that natural processes can cause organisms to develop over time. This includes the emergence and development of new species.<br /><br />Numerous examples have been offered of this, such as different kinds of stickleback fish that can live in either salt or fresh water, as well as walking stick insect varieties that are attracted to particular host plants. These reversible traits cannot explain fundamental changes to the body's basic plans.<br /><br />Evolution through Natural Selection<br /><br />The development of the myriad of living organisms on Earth is an enigma that has intrigued scientists for many centuries. Charles Darwin's natural selectivity is the most well-known explanation. This is because individuals who are better-adapted are able to reproduce faster and longer than those who are less well-adapted. Over time, a community of well adapted individuals grows and eventually becomes a new species.<br /><br />Natural selection is an ongoing process and involves the interaction of 3 factors that are: reproduction, variation and inheritance. Variation is caused by mutations and sexual reproduction both of which enhance the genetic diversity within the species. Inheritance is the term used to describe the transmission of a person's genetic characteristics, which includes both dominant and recessive genes to their offspring. Reproduction is the process of producing fertile, viable offspring. This can be accomplished by both asexual or sexual methods.<br /><br />All of these elements must be in balance for natural selection to occur. If, for instance, a dominant gene allele makes an organism reproduce and live longer than the recessive allele The dominant allele is more common in a population. But if the allele confers a disadvantage in survival or decreases fertility, it will disappear from the population. The process is self reinforcing, which means that an organism that has an adaptive characteristic will live and reproduce far more effectively than one with a maladaptive characteristic. The more offspring that an organism has the more fit it is which is measured by its ability to reproduce itself and survive. People with desirable characteristics, like having a longer neck in giraffes and bright white patterns of color in male peacocks, are more likely to survive and have offspring, and thus will make up the majority of the population in the future.<br /><br />Natural selection is only an aspect of populations and not on individuals. This is an important distinction from the Lamarckian theory of evolution which states that animals acquire characteristics by use or inactivity. If a giraffe expands its neck to catch prey and the neck grows longer, then its offspring will inherit this trait. The differences in neck length between generations will continue until the neck of the giraffe becomes too long that it can not breed with other giraffes.<br /><br />Evolution by Genetic Drift<br /><br />In the process of genetic drift, alleles of a gene could attain different frequencies in a population due to random events. At some point, only one of them will be fixed (become widespread enough to not more be eliminated through natural selection), and the other alleles drop in frequency. In the extreme, this leads to dominance of a single allele. The other alleles are eliminated, and heterozygosity falls to zero. In a small population, this could lead to the complete elimination of recessive allele. Such a scenario would be called a bottleneck effect, and it is typical of the kind of evolutionary process that occurs when a large amount of people migrate to form a new population.<br /><br />A phenotypic bottleneck may also occur when the survivors of a catastrophe like an outbreak or a mass hunting incident are concentrated in a small area. <a href="https://evolutionkr.kr/">evolutionkr</a> will carry an allele that is dominant and will share the same phenotype. This situation could be caused by war, earthquakes or even a plague. The genetically distinct population, if left, could be susceptible to genetic drift.<br /><br />Walsh Lewens, Lewens, and Ariew utilize a "purely outcome-oriented" definition of drift as any departure from the expected values of differences in fitness. They give the famous example of twins that are genetically identical and share the same phenotype. However one is struck by lightning and dies, while the other continues to reproduce.<br /><br /><br /><br />This type of drift can play a crucial part in the evolution of an organism. This isn't the only method of evolution. The main alternative is a process known as natural selection, in which phenotypic variation in an individual is maintained through mutation and migration.<br /><br />Stephens asserts that there is a big difference between treating the phenomenon of drift as a force or as an underlying cause, and considering other causes of evolution such as selection, mutation, and migration as forces or causes. He argues that a causal-process model of drift allows us to distinguish it from other forces and that this distinction is crucial. He also argues that drift has both a direction, i.e., it tends to reduce heterozygosity. It also has a size, which is determined based on the size of the population.<br /><br />Evolution through Lamarckism<br /><br />In high school, students study biology they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution is commonly referred to as "Lamarckism" and it asserts that simple organisms evolve into more complex organisms through the inheritance of characteristics that result from the organism's natural actions usage, use and disuse. Lamarckism is typically illustrated by the image of a giraffe stretching its neck further to reach higher up in the trees. This process would result in giraffes passing on their longer necks to their offspring, who then become taller.<br /><br />Lamarck was a French zoologist and, in his lecture to begin his course on invertebrate zoology at the Museum of Natural History in Paris on the 17th of May in 1802, he presented an innovative concept that completely challenged the conventional wisdom about organic transformation. In his opinion, living things had evolved from inanimate matter via an escalating series of steps. Lamarck was not the first to make this claim however he was widely regarded as the first to offer the subject a thorough and general explanation.<br /><br />The predominant story is that Charles Darwin's theory on natural selection and Lamarckism were competing in the 19th Century. Darwinism eventually prevailed and led to the creation of what biologists now call the Modern Synthesis. The theory argues that acquired characteristics can be acquired through inheritance and instead argues that organisms evolve through the action of environmental factors, such as natural selection.<br /><br />While Lamarck endorsed the idea of inheritance by acquired characters and his contemporaries spoke of this idea but it was not an integral part of any of their theories about evolution. This is partly due to the fact that it was never tested scientifically.<br /><br />It's been more than 200 years since Lamarck was born and, in the age of genomics, there is a large amount of evidence that supports the possibility of inheritance of acquired traits. This is also referred to as "neo Lamarckism", or more generally epigenetic inheritance. It is a variant of evolution that is as valid as the more well-known Neo-Darwinian model.<br /><br />Evolution through the process of adaptation<br /><br />One of the most widespread misconceptions about evolution is that it is driven by a type of struggle for survival. In fact, this view is a misrepresentation of natural selection and ignores the other forces that drive evolution. The struggle for existence is better described as a fight to survive in a specific environment. This may be a challenge for not just other living things, but also the physical environment itself.<br /><br />To understand how evolution works it is important to understand what is adaptation. It refers to a specific characteristic that allows an organism to survive and reproduce within its environment. It could be a physical structure like fur or feathers. Or it can be a behavior trait, like moving to the shade during hot weather or escaping the cold at night.<br /><br />The capacity of a living thing to extract energy from its surroundings and interact with other organisms, as well as their physical environments is essential to its survival. The organism must possess the right genes to create offspring and to be able to access sufficient food and resources. Furthermore, the organism needs to be able to reproduce itself in a way that is optimally within its niche.<br /><br />These factors, in conjunction with mutations and gene flow can result in an alteration in the ratio of different alleles within the population's gene pool. The change in frequency of alleles can result in the emergence of new traits and eventually new species as time passes.<br /><br />Many of the features we find appealing in plants and animals are adaptations. For example lung or gills that draw oxygen from air feathers and fur for insulation and long legs to get away from predators and camouflage to conceal. To understand adaptation it is essential to distinguish between behavioral and physiological traits.<br /><br />Physiological adaptations like the thick fur or gills are physical traits, whereas behavioral adaptations, such as the tendency to search for friends or to move to shade in hot weather, are not. Additionally it is important to remember that a lack of thought does not mean that something is an adaptation. Inability to think about the implications of a choice even if it appears to be logical, can cause it to be unadaptive.<br /><br />
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