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What is Free Evolution?

Free evolution is the idea that natural processes can cause organisms to evolve over time. This includes the evolution of new species and alteration of the appearance of existing ones.

This is evident in many examples of stickleback fish species that can live in salt or fresh water, and walking stick insect varieties that have a preference for specific host plants. These typically reversible traits do not explain the fundamental changes in the basic body plan.

Evolution through Natural Selection

The development of the myriad of living organisms on Earth is an enigma that has fascinated scientists for decades. The most well-known explanation is Darwin's natural selection, 무료에볼루션 블랙잭 (www.Guoziweb.com) an evolutionary process that is triggered when more well-adapted individuals live longer and reproduce more effectively than those who are less well adapted. Over time, the population of individuals who are well-adapted grows and eventually creates an entirely new species.

Natural selection is a cyclical process that is characterized by the interaction of three elements: variation, inheritance and reproduction. Variation is caused by mutations and sexual reproduction, both of which increase the genetic diversity of the species. Inheritance refers to the passing of a person's genetic characteristics to their offspring that includes dominant and recessive alleles. Reproduction is the production of viable, fertile offspring, which includes both asexual and sexual methods.

Natural selection is only possible when all of these factors are in equilibrium. If, for instance, a dominant gene allele makes an organism reproduce and last longer than the recessive allele, then the dominant allele becomes more prevalent in a population. If the allele confers a negative advantage to survival or reduces the fertility of the population, it will go away. The process is self-reinforcing meaning that the organism with an adaptive trait will live and reproduce more quickly than those with a maladaptive trait. The more offspring an organism can produce the more fit it is that is determined by its ability to reproduce and survive. People with desirable traits, such as longer necks in giraffes or 에볼루션 룰렛 bright white color patterns in male peacocks are more likely to survive and have offspring, and thus will become the majority of the population over time.

Natural selection is only an element in the population and not on individuals. This is a major 무료에볼루션 distinction from the Lamarckian theory of evolution, which argues that animals acquire characteristics through use or disuse. For instance, if the animal's neck is lengthened by stretching to reach for prey and its offspring will inherit a more long neck. The length difference between generations will persist until the neck of the giraffe becomes so long that it can no longer breed with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles from the same gene are randomly distributed in a group. In the end, one will attain fixation (become so common that it cannot be removed by natural selection), while other alleles will fall to lower frequency. This can lead to a dominant allele in the extreme. The other alleles are essentially eliminated, and heterozygosity is reduced to zero. In a small number of people, this could lead to the complete 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 migrate to form a new group.

A phenotypic bottleneck can also occur when the survivors of a disaster like an outbreak or mass hunt incident are concentrated in the same area. The remaining individuals will be largely homozygous for the dominant allele meaning that they all have the same phenotype and consequently have the same fitness traits. This may be caused by a conflict, earthquake, or even a plague. The genetically distinct population, if it is left vulnerable to genetic drift.

Walsh Lewens and Ariew employ Lewens, Walsh and Ariew employ a "purely outcome-oriented" definition of drift as any deviation from the expected values for variations in fitness. They provide a well-known example of twins that are genetically identical and have identical phenotypes, but one is struck by lightning and dies, whereas the other lives and reproduces.

This kind of drift could play a very important role in the evolution of an organism. This isn't the only method of evolution. The most common alternative is to use a process known as natural selection, where the phenotypic variation of a population is maintained by mutation and migration.

Stephens claims that there is a big difference between treating the phenomenon of drift as a force, or a cause and considering other causes of evolution like selection, mutation and migration as forces or causes. He claims that a causal process account of drift allows us to distinguish it from the other forces, and this distinction is essential. He further argues that drift has both an orientation, 무료 에볼루션 i.e., it tends to eliminate heterozygosity. It also has a size, which is determined by population size.

Evolution by Lamarckism

In high school, students take biology classes, they are frequently introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, commonly referred to as "Lamarckism", states that simple organisms transform into more complex organisms through adopting traits that result from an organism's use and disuse. Lamarckism is usually illustrated with the image of a giraffe that extends its neck longer to reach higher up in the trees. This could cause giraffes to give their longer necks to offspring, 무료 에볼루션 who would then grow even taller.

Lamarck was a French Zoologist. In his lecture to begin his course on invertebrate Zoology at the Museum of Natural History in Paris on the 17th May 1802, he introduced a groundbreaking concept that radically challenged previous thinking about organic transformation. According to him living things evolved from inanimate matter through the gradual progression of events. Lamarck was not the only one to suggest that this might be the case but the general consensus is that he was the one giving the subject its first broad and comprehensive treatment.

The most popular story is that Lamarckism was an opponent to Charles Darwin's theory of evolution by natural selection, and that the two theories battled each other in the 19th century. Darwinism eventually prevailed which led to what biologists call the Modern Synthesis. The theory argues that acquired traits can be passed down and instead argues organisms evolve by the selective influence of environmental factors, including Natural Selection.

While Lamarck supported the notion of inheritance by acquired characters and his contemporaries also offered a few words about this idea but it was not a central element in any of their theories about evolution. This is due to the fact that it was never scientifically validated.

It's been more than 200 years since Lamarck was born and in the age of genomics there is a vast body of evidence supporting the heritability of acquired characteristics. This is referred to as "neo Lamarckism", or more generally epigenetic inheritance. It is a form of evolution that is as valid as the more popular Neo-Darwinian model.

Evolution through the process of adaptation

One of the most popular misconceptions about evolution is its being driven by a fight for survival. This is a false assumption and ignores other forces driving evolution. The struggle for survival is more effectively described as a struggle to survive within a specific environment, which could involve not only other organisms but also the physical environment itself.

Understanding how adaptation works is essential to comprehend evolution. It refers to a specific feature that allows an organism to survive and reproduce in its environment. It can be a physical feature, such as feathers or fur. It could also be a trait of behavior that allows you to move to the shade during hot weather or coming out to avoid the cold at night.

An organism's survival depends on its ability to draw energy from the environment and interact with other organisms and their physical environments. The organism should possess the right genes to produce offspring and to be able to access enough food and resources. Moreover, the organism must be capable of reproducing itself at an optimal rate within its environment.

These elements, in conjunction with mutation and gene flow, lead to a change in the proportion of alleles (different forms of a gene) in the gene pool of a population. Over time, this change in allele frequencies can lead to the emergence of new traits and eventually new species.

Many of the characteristics we appreciate in plants and animals are adaptations. For instance lung or gills that extract oxygen from air, fur and feathers as insulation and long legs to get away from predators and camouflage for hiding. However, a complete understanding of adaptation requires attention to the distinction between the physiological and behavioral traits.

Physiological adaptations, like thick fur or gills are physical traits, whereas behavioral adaptations, such as the tendency to seek out friends or to move to shade in hot weather, are not. It is important to remember that a lack of planning does not make an adaptation. In fact, a failure to think about the consequences of a behavior can make it unadaptable even though it appears to be reasonable or even essential.