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What is Free Evolution?

Free evolution is the concept that the natural processes that organisms go through can lead to their development over time. This includes the evolution of new species as well as the alteration of the appearance of existing ones.

Many examples have been given of this, including different kinds of stickleback fish that can live in either fresh or salt water and walking stick insect varieties that favor particular host plants. These typically reversible traits cannot explain fundamental changes to the basic body plan.

Evolution by Natural Selection

The evolution of the myriad living creatures on Earth is a mystery that has fascinated scientists for centuries. Charles Darwin's natural selection theory is the best-established explanation. This is because individuals who are better-adapted have more success in reproduction and survival than those who are less well-adapted. Over time, the population of individuals who are well-adapted grows and eventually develops into an entirely new species.

Natural selection is a cyclical process that is characterized by the interaction of three factors that are inheritance, variation and reproduction. Variation is caused by mutation and sexual reproduction both of which increase the genetic diversity within a species. Inheritance is the passing of a person's genetic characteristics to the offspring of that person which includes both recessive and dominant alleles. Reproduction is the process of creating fertile, viable offspring. This can be done via sexual or asexual methods.

Natural selection can only occur when all these elements are in balance. For example when an allele that is dominant at one gene can cause an organism to live and reproduce more often than the recessive allele, the dominant allele will become more prominent within the population. However, if the gene confers a disadvantage in survival or reduces fertility, it will disappear from the population. This process is self-reinforcing which means that the organism with an adaptive trait will survive and reproduce far more effectively than those with a maladaptive feature. The more offspring an organism produces the better its fitness, 에볼루션 바카라 which is measured by its capacity to reproduce itself and survive. People with good traits, such as having a longer neck in giraffes and bright white colors in male peacocks are more likely survive and produce offspring, so they will eventually make up the majority of the population in the future.

Natural selection only acts on populations, not individuals. This is a significant distinction from the Lamarckian theory of evolution, which states that animals acquire traits through use or neglect. For example, if a animal's neck is lengthened by stretching to reach prey its offspring will inherit a more long neck. The differences in neck size between generations will continue to increase until the giraffe is unable to breed with other giraffes.

Evolution through Genetic Drift

In genetic drift, the alleles at a gene may attain different frequencies in a group by chance events. At some point, only one of them will be fixed (become common enough that it can no longer be eliminated by natural selection), and the other alleles diminish in frequency. In the extreme this, it leads to one allele dominance. The other alleles are essentially eliminated and heterozygosity has diminished to zero. In a small group, this could lead to the complete elimination of recessive allele. This scenario is called the bottleneck effect and is typical of the evolutionary process that occurs whenever an enormous number of individuals move to form a group.

A phenotypic 'bottleneck' can also occur when the survivors of a catastrophe such as an outbreak or mass hunting incident are concentrated in the same area. The survivors will share a dominant allele and thus will have the same phenotype. This may be the result of a war, 에볼루션 슬롯게임 earthquake, or even a plague. Whatever the reason the genetically distinct population that is left might be prone to genetic drift.

Walsh, Lewens and Ariew define drift as a departure from expected values due to differences in fitness. They provide the famous case of twins who are both genetically identical and have exactly the same phenotype. However, one is struck by lightning and dies, but the other lives to reproduce.

This type of drift can play a significant role in the evolution of an organism. This isn't the only method of evolution. Natural selection is the most common alternative, where mutations and migration maintain the phenotypic diversity of the population.

Stephens asserts that there is a huge distinction between treating drift as an actual cause or 에볼루션사이트 force, and considering other causes, such as migration and selection as forces and causes. He claims that a causal-process account of drift allows us distinguish it from other forces and this differentiation is crucial. He further argues that drift is a directional force: that is it tends to reduce heterozygosity. He also claims that it also has a magnitude, which is determined by the size of population.

Evolution through Lamarckism

Biology students in high school are often introduced to Jean-Baptiste Lamarck's (1744-1829) work. His theory of evolution is generally referred to as "Lamarckism" and 무료에볼루션 it states that simple organisms grow into more complex organisms through the inheritance of traits which result from the natural activities of an organism use and misuse. Lamarckism is illustrated through the giraffe's neck being extended to reach higher branches in the trees. This could cause giraffes to pass on their longer necks to offspring, who would then grow even taller.

Lamarck was a French zoologist and, in his opening lecture for his course on invertebrate zoology 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 Lamarck, 에볼루션 바카라사이트 living things evolved from inanimate material through a series gradual steps. Lamarck was not the first to suggest that this could be the case but he is widely seen as giving the subject his first comprehensive and thorough treatment.

The dominant story is that Charles Darwin's theory on natural selection and Lamarckism were rivals during the 19th century. Darwinism ultimately prevailed, leading to what biologists refer to as the Modern Synthesis. This theory denies that traits acquired through evolution can be inherited, and instead argues that organisms evolve by the symbiosis of environmental factors, like natural selection.

Lamarck and his contemporaries endorsed the idea that acquired characters could be passed on to the next generation. However, this concept was never a major part of any of their theories about evolution. This is partly because it was never scientifically tested.

It has been more than 200 year since Lamarck's birth and in the field of age genomics, there is a growing evidence base that supports the heritability-acquired characteristics. It is sometimes called "neo-Lamarckism" or more commonly epigenetic inheritance. This is a variant that is as reliable as the popular neodarwinian model.

Evolution by adaptation

One of the most common misconceptions about evolution is being driven by a struggle to survive. In fact, this view misrepresents natural selection and ignores the other forces that determine the rate of evolution. The fight for survival can be better described as a struggle to survive in a specific environment. This may be a challenge for not just other living things but also the physical environment.

To understand how evolution operates it is beneficial to consider what adaptation is. The term "adaptation" refers to any characteristic that allows living organisms to survive in its environment and reproduce. It could be a physiological structure such as fur or feathers or a behavioral characteristic such as a tendency to move into the shade in the heat or leaving at night to avoid cold.

The ability of a living thing to extract energy from its environment and interact with other organisms as well as their physical environment, is crucial to its survival. The organism must possess the right genes to create offspring, and it should be able to locate sufficient food and other resources. The organism should be able to reproduce itself at an amount that is appropriate for its niche.

These elements, in conjunction with gene flow and mutation, lead to changes in the ratio of alleles (different forms of a gene) in the gene pool of a population. The change in frequency of alleles could lead to the development of new traits, and eventually, new species in the course of time.

A lot of the traits we admire in plants and animals are adaptations. For example the lungs or gills which extract oxygen from the air feathers and fur for insulation long legs to run away from predators, and camouflage to hide. To understand adaptation, it is important to differentiate between physiological and behavioral traits.

Physiological adaptations, such as the thick fur or gills are physical traits, while behavioral adaptations, like the tendency to seek out companions or to move into the shade in hot weather, are not. It is important to keep in mind that the absence of planning doesn't make an adaptation. In fact, failing to consider the consequences of a decision can render it ineffective, despite the fact that it might appear reasonable or even essential.