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What is Free Evolution?

Free evolution is the notion that the natural processes that organisms go through can lead to their development over time. This includes the development of new species and the transformation of the appearance of existing ones.

This is evident in many examples of stickleback fish species that can thrive in fresh or saltwater and walking stick insect varieties that prefer specific host plants. These reversible traits, 에볼루션 룰렛게이밍, https://telegra.ph/The-Main-Issue-With-Evolution-Baccarat-And-How-You-Can-Solve-It-12-21, however, cannot explain fundamental changes in basic body plans.

Evolution by Natural Selection

Scientists have been fascinated by the evolution of all the living creatures that inhabit our planet for many centuries. The best-established explanation is that of Charles Darwin's natural selection process, an evolutionary process that occurs when individuals that are better adapted survive and reproduce more effectively than those less well adapted. As time passes, the number of well-adapted individuals grows and eventually creates an entirely new species.

Natural selection is an ongoing process and involves the interaction of 3 factors that are: reproduction, variation and inheritance. Variation is caused by mutation and sexual reproduction both of which increase the genetic diversity within the species. Inheritance refers to the passing of a person's genetic characteristics to their offspring which includes both dominant and recessive alleles. Reproduction is the production of fertile, viable offspring which includes both asexual and sexual methods.

Natural selection can only occur when all the factors are in harmony. For example when a dominant allele at one gene causes an organism to survive and reproduce more often than the recessive allele the dominant allele will become more prominent in the population. However, if the allele confers an unfavorable survival advantage or decreases fertility, it will disappear from the population. This process is self-reinforcing meaning that a species that has a beneficial trait can reproduce and survive longer than one with an inadaptive characteristic. The greater an organism's fitness which is measured by its ability to reproduce and survive, is the greater number of offspring it produces. People with desirable characteristics, like having a longer neck in giraffes, or bright white patterns of color in male peacocks, are more likely to survive and produce offspring, so they will make up the majority of the population over time.

Natural selection only acts on populations, not on individuals. This is a major distinction from the Lamarckian theory of evolution which states that animals acquire characteristics through use or neglect. If a giraffe stretches its neck to reach prey, and the neck becomes larger, then its children will inherit this characteristic. The differences in neck length between generations will persist until the neck of the giraffe becomes so long that it can not breed with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles from the same gene are randomly distributed within a population. Eventually, one of them will attain fixation (become so widespread that it cannot be eliminated through natural selection) and other alleles fall to lower frequencies. In extreme cases, this leads to dominance of a single allele. The other alleles have been basically eliminated and heterozygosity has been reduced to zero. In a small group this could lead to the complete elimination of recessive gene. This is known as the bottleneck effect and is typical of an evolutionary process that occurs when the number of individuals migrate to form a population.

A phenotypic 'bottleneck' can also occur when survivors of a disaster like an outbreak or mass hunt event are concentrated in the same area. The survivors will share a dominant allele and thus will have the same phenotype. This situation could be caused by earthquakes, war or even a plague. Regardless of the cause the genetically distinct group that remains is prone to genetic drift.

Walsh, Lewens and Ariew define drift as a departure from expected values due to differences in fitness. They give a famous example of twins that are genetically identical, share identical phenotypes, but one is struck by lightning and dies, while the other lives and reproduces.

This kind of drift can be vital to the evolution of a species. However, it is not the only way to evolve. Natural selection is the most common alternative, where mutations and migration keep phenotypic diversity within the population.

Stephens asserts that there is a major difference between treating drift as a force, or an underlying cause, and considering other causes of evolution such as mutation, selection and migration as forces or causes. He claims that a causal mechanism account of drift allows us to distinguish it from other forces, and this distinction is essential. He also argues that drift has a direction: that is, it tends to eliminate heterozygosity, and 에볼루션 룰렛 슬롯게임 [Beyer-Harrell-3.Blogbright.Net] that it also has a size, that is determined by the size of population.

Evolution by Lamarckism

In high school, students study biology, they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, also referred to as "Lamarckism is based on the idea that simple organisms transform into more complex organisms through adopting traits that result from the organism's use and misuse. Lamarckism is typically illustrated by a picture of a giraffe extending its neck longer to reach the higher branches in the trees. This could cause giraffes to pass on their longer necks to offspring, who would then get taller.

Lamarck was a French zoologist and, in his inaugural lecture for his course on invertebrate zoology at the Museum of Natural History in Paris on 17 May 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 through a series of gradual steps. Lamarck was not the only one to suggest that this could be the case but the general consensus is that he was the one giving the subject its first broad and comprehensive analysis.

The prevailing story is that Lamarckism grew into an opponent to Charles Darwin's theory of evolutionary natural selection and both theories battled each other in the 19th century. Darwinism eventually won and led to the development of what biologists today call the Modern Synthesis. The theory argues that acquired traits are passed down from generation to generation and instead argues that organisms evolve through the influence of environment factors, such as Natural Selection.

While Lamarck endorsed the idea of inheritance through acquired characters and his contemporaries also spoke of this idea however, it was not a central element in any of their evolutionary theories. This is largely due to the fact that it was never validated scientifically.

However, it has been more than 200 years since Lamarck was born and in the age of genomics there is a vast body of evidence supporting the possibility of inheritance of acquired traits. This is referred to as "neo Lamarckism", or more often epigenetic inheritance. It is a form of evolution that is as relevant as the more popular Neo-Darwinian model.

Evolution through Adaptation

One of the most common misconceptions about evolution is that it is being driven by a fight for survival. This view is inaccurate and ignores other forces driving evolution. The fight for survival is more accurately described as a struggle to survive in a specific environment. This can be a challenge for not just other living things, but also the physical surroundings themselves.

To understand how evolution operates it is beneficial to think about what adaptation is. It is a feature that allows living organisms to live in its environment and reproduce. It can be a physical feature, like feathers or fur. Or it can be a characteristic of behavior that allows you to move into the shade during hot weather, or coming out to avoid the cold at night.

The survival of an organism is dependent on its ability to draw energy from the environment and interact with other living organisms and their physical surroundings. The organism must possess the right genes to create offspring, and must be able to access sufficient food and other resources. The organism must also be able to reproduce itself at a rate that is optimal for its particular niche.

These factors, together with mutation and gene flow can result in an alteration in the percentage of alleles (different forms of a gene) in the population's gene pool. Over time, this change in allele frequency can result in the emergence of new traits and eventually new species.

A lot of the traits we find appealing in animals and plants are adaptations. For instance lung or gills that draw oxygen from air feathers and fur as insulation, long legs to run away from predators and camouflage for hiding. However, a thorough understanding of adaptation requires paying attention to the distinction between behavioral and physiological characteristics.

Physiological adaptations like the thick fur or gills are physical traits, whereas behavioral adaptations, like the tendency to search for friends or to move into the shade in hot weather, are not. Furthermore 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 make it inflexible.