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What is Free Evolution? Free evolution is the concept that the natural processes of living organisms can cause them to develop over time. This includes the emergence and development of new species. hop over to here have been offered of this, including different kinds of stickleback fish that can live in either fresh or salt water and walking stick insect varieties that are attracted to particular host plants. These mostly reversible trait permutations, however, cannot explain fundamental changes in basic body plans. Evolution by Natural Selection The development of the myriad living organisms on Earth is a mystery that has fascinated scientists for many centuries. Charles Darwin's natural selection is the most well-known explanation. This process occurs when individuals who are better-adapted have more success in reproduction and survival than those who are less well-adapted. Over time, a population of well-adapted individuals expands and eventually creates a new species. Natural selection is a process that is cyclical and involves the interaction of 3 factors that are: reproduction, variation and inheritance. Sexual reproduction and mutations increase genetic diversity in the species. Inheritance refers to the passing of a person's genetic traits to the offspring of that person which includes both dominant and recessive alleles. Reproduction is the process of producing viable, fertile offspring, which includes both sexual and asexual methods. All of these elements must be in balance for natural selection to occur. For instance the case where the dominant allele of one gene can cause an organism to live and reproduce more often than the recessive allele, the dominant allele will become more common within the population. However, if the gene confers an unfavorable survival advantage or reduces fertility, it will disappear from the population. The process is self-reinforced, meaning that a species with a beneficial trait is more likely to survive and reproduce than one with an unadaptive characteristic. The more offspring an organism can produce, the greater its fitness, which is measured by its ability to reproduce itself and survive. Individuals with favorable traits, like having a longer neck in giraffes or bright white patterns of color in male peacocks, are more likely to be able to survive and create offspring, which means they will eventually make up the majority of the population in the future. Natural selection only affects populations, not on individuals. This is a significant distinction from the Lamarckian theory of evolution which states that animals acquire characteristics through use or disuse. For instance, if a animal's neck is lengthened by stretching to reach for prey, its offspring will inherit a longer neck. The length difference between generations will persist until the neck of the giraffe becomes too long that it can no longer breed with other giraffes. Evolution by Genetic Drift Genetic drift occurs when the alleles of one gene are distributed randomly in a group. At some point, one will reach fixation (become so common that it cannot be eliminated through natural selection), while the other alleles drop to lower frequency. This can lead to dominance in extreme. Other alleles have been virtually eliminated and heterozygosity been reduced to a minimum. In a small group, this could lead to the total elimination of recessive allele. This is known as a bottleneck effect and it is typical of the kind of evolutionary process that occurs when a large number of individuals move to form a new population. A phenotypic bottleneck can also occur when survivors of a disaster such as an epidemic or a mass hunting event, are concentrated within a narrow area. The remaining individuals will be mostly homozygous for the dominant allele which means they will all share the same phenotype and therefore have the same fitness characteristics. This could be caused by war, earthquakes, or even plagues. The genetically distinct population, if left vulnerable to genetic drift. Walsh Lewens, Walsh, and Ariew define drift as a deviation from expected values due to differences in fitness. They give the famous example of twins who are both genetically identical and have exactly the same phenotype. However one is struck by lightning and dies, but the other continues to reproduce. This type of drift is very important in the evolution of an entire species. It's not the only method for evolution. Natural selection is the most common alternative, where mutations and migrations maintain the phenotypic diversity in the population. Stephens argues there is a significant difference between treating drift like an actual cause or force, and considering other causes, such as migration and selection as causes and forces. He argues that a causal-process model of drift allows us to separate it from other forces, and this differentiation is crucial. He further argues that drift has an orientation, i.e., it tends towards eliminating heterozygosity. It also has a size, which is determined by the size of the population. Evolution by Lamarckism When students in high school take biology classes, they are frequently introduced to the work of Jean-Baptiste Lamarck (1744 – 1829). His theory of evolution is generally known as “Lamarckism” and it states that simple organisms develop into more complex organisms through the inheritance of characteristics which result from the natural activities of an organism use and misuse. Lamarckism is typically illustrated by an image of a giraffe extending its neck further to reach leaves higher up in the trees. This process would cause giraffes to give their longer necks to offspring, who then grow even taller. Lamarck was a French zoologist and, in his opening lecture for his course on invertebrate zoology held at the Museum of Natural History in Paris on 17 May 1802, he introduced an innovative concept that completely challenged previous thinking about organic transformation. According to him, living things had evolved from inanimate matter through the gradual progression of events. Lamarck wasn't the only one to make this claim but he was considered to be the first to provide the subject a thorough and general treatment. The popular narrative is that Lamarckism was a rival to Charles Darwin's theory of evolution through natural selection, and both theories battled it out in the 19th century. Darwinism eventually prevailed and led to the creation of what biologists call the Modern Synthesis. The theory denies that acquired characteristics are passed down from generation to generation and instead argues organisms evolve by the selective action of environment elements, like Natural Selection. Although Lamarck endorsed the idea of inheritance through acquired characters, and his contemporaries also paid lip-service to this notion, it was never a major feature in any of their evolutionary theorizing. This is due to the fact that it was never scientifically validated. It has been more than 200 years since the birth of Lamarck, and in the age genomics, there is an increasing evidence-based body of evidence to support the heritability-acquired characteristics. This is often referred to as “neo-Lamarckism” or, more commonly epigenetic inheritance. It is a version of evolution that is as valid as the more popular neo-Darwinian model. Evolution by adaptation One of the most popular misconceptions about evolution is that it is being driven by a struggle for survival. This notion is not true and overlooks other forces that drive evolution. The struggle for survival is more accurately described as a struggle to survive within a particular environment, which could involve not only other organisms but also the physical environment. To understand how evolution operates it is beneficial to think about what adaptation is. The term “adaptation” refers to any specific feature that allows an organism to survive and reproduce in its environment. It can be a physical structure like fur or feathers. Or it can be a characteristic of behavior, like moving into the shade during the heat, or coming out to avoid the cold at night. The ability of a living thing to extract energy from its environment and interact with other organisms, as well as their physical environments, is crucial to its survival. The organism should possess the right genes for producing offspring and to be able to access enough food and resources. The organism should also be able to reproduce at an amount that is appropriate for its specific niche. These factors, in conjunction with mutations and gene flow can result in a shift in the proportion of different alleles within the population's gene pool. This shift in the frequency of alleles can lead to the emergence of new traits, and eventually new species in the course of time. Many of the characteristics we admire in animals and plants are adaptations, such as lungs or gills to extract oxygen from the air, feathers or fur to protect themselves, long legs for running away from predators and camouflage for hiding. However, a proper understanding of adaptation requires attention to the distinction between the physiological and behavioral characteristics. Physical characteristics like the thick fur and gills are physical traits. Behavioral adaptations are not, such as the tendency of animals to seek companionship or retreat into shade in hot weather. It is also important to note that the absence of planning doesn't result in an adaptation. In fact, failure to consider the consequences of a decision can render it unadaptable, despite the fact that it might appear sensible or even necessary.