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What is Free Evolution?

Free evolution is the idea that natural processes can lead to the development of organisms over time. This includes the appearance and development of new species.


This is evident in numerous examples such as the stickleback fish species that can live in salt or fresh water, and walking stick insect types that prefer particular host plants. These typically reversible traits cannot explain fundamental changes to the body's basic plans.

Evolution by Natural Selection

The evolution of the myriad living organisms on Earth is an enigma that has intrigued scientists for decades. Charles Darwin's natural selectivity is the best-established explanation. This process occurs when people who are more well-adapted survive and reproduce more than those who are less well-adapted. Over time, the population of well-adapted individuals grows and eventually forms an entirely new species.

Natural selection is an ongoing process that is characterized by the interaction of three factors: variation, inheritance and reproduction. Mutation and sexual reproduction increase genetic diversity in a species. Inheritance refers the transmission of genetic characteristics, which includes both dominant and recessive genes, to their offspring. Reproduction is the process of producing fertile, viable offspring which includes both asexual and sexual methods.

All of these factors have to be in equilibrium for natural selection to occur. If, for instance, a dominant gene allele allows an organism to reproduce and live longer than the recessive allele The dominant allele becomes more prevalent in a group. If the allele confers a negative advantage to survival or decreases the fertility of the population, it will be eliminated. This process is self-reinforcing which means that an organism that has a beneficial trait is more likely to survive and reproduce than one with an inadaptive characteristic. The higher the level of fitness an organism has, measured by its ability reproduce and endure, is the higher number of offspring it produces. People with desirable traits, like a longer neck in giraffes, or bright white color patterns in male peacocks, are more likely to be able to survive and create offspring, so they will eventually make up the majority of the population in the future.

Natural selection only affects populations, not on individuals. This is a crucial distinction from the Lamarckian theory of evolution that states that animals acquire traits due to the use or absence of use. For instance, if a Giraffe's neck grows longer due to stretching to reach prey, its offspring will inherit a larger neck. The length difference between generations will persist until the neck of the giraffe becomes too long that it can not breed with other giraffes.

Evolution through Genetic Drift

Genetic drift occurs when alleles of one gene are distributed randomly within a population. At ???? ?? ??? , one will reach fixation (become so common that it cannot be removed by natural selection) and the other alleles drop to lower frequencies. In the extreme this, it leads to dominance of a single allele. The other alleles are eliminated, and heterozygosity is reduced to zero. In a small number of people, this could result in the complete elimination of the recessive gene. Such a scenario would be known as a bottleneck effect and it is typical of the kind of evolutionary process that takes place when a large amount of people migrate to form a new population.

A phenotypic bottleneck may also occur when survivors of a disaster such as an outbreak or mass hunting event are concentrated in the same area. The survivors will carry an dominant allele, and will have the same phenotype. This situation could be caused by earthquakes, war, or even plagues. Whatever the reason, the genetically distinct population that remains is prone to genetic drift.

Walsh Lewens, Walsh, and Ariew define drift as a deviation from the expected value 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, whereas the other lives to reproduce.

This kind of drift could play a very important role in the evolution of an organism. This isn't the only method for evolution. Natural selection is the primary alternative, in which mutations and migration keep phenotypic diversity within a population.

Stephens claims that there is a major distinction between treating drift as a force or as an underlying cause, and considering other causes of evolution, such as selection, mutation and migration as causes or causes. Stephens claims that a causal process account of drift allows us to distinguish it from the other forces, and that this distinction is crucial. He argues further that drift has both direction, i.e., it tends to eliminate heterozygosity. It also has a size that is determined by the size of the population.

Evolution through Lamarckism

In high school, students study biology, they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, commonly called "Lamarckism, states that simple organisms evolve into more complex organisms through taking on traits that result from the organism's use and misuse. Lamarckism can be illustrated by a giraffe extending its neck to reach higher leaves in the trees. This would cause giraffes to pass on their longer necks to their offspring, which then grow even taller.

Lamarck, a French Zoologist, introduced an idea that was revolutionary in his 17 May 1802 opening lecture at the Museum of Natural History of Paris. He challenged previous thinking on organic transformation. According to Lamarck, living creatures 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 his reputation is widely regarded as having given the subject its first general and comprehensive analysis.

The prevailing story is that Lamarckism became a rival to Charles Darwin's theory of evolutionary natural selection, and that the two theories fought each other in the 19th century. Darwinism eventually prevailed which led to what biologists refer to as the Modern Synthesis. The theory argues that acquired traits are passed down from generation to generation and instead, it claims that organisms evolve through the selective influence of environmental elements, like Natural Selection.

Although Lamarck believed in the concept of inheritance by acquired characters and his contemporaries offered a few words about this idea however, it was not a central element in any of their evolutionary theorizing. This is partly because it was never scientifically validated.

It has been more than 200 year since Lamarck's birth, and in the age genomics there is a growing evidence-based body of evidence to support the heritability acquired characteristics. This is sometimes referred to as "neo-Lamarckism" or, more commonly epigenetic inheritance. This is a model that is as valid as the popular neodarwinian model.

Evolution by the process of adaptation

One of the most common misconceptions about evolution is being driven by a struggle for survival. In fact, this view misrepresents natural selection and ignores the other forces that are driving evolution. The struggle for existence is more accurately described as a struggle to survive in a certain environment. This could include not just other organisms as well as the physical environment.

To understand how evolution works it is beneficial to think about what adaptation is. The term "adaptation" refers to any characteristic that allows a living thing to live in its environment and reproduce. It can be a physiological structure like feathers or fur or a behavior like moving into shade in the heat or leaving at night to avoid the cold.

The capacity of an organism 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 have the right genes for producing offspring and be able find enough food and resources. The organism must be able to reproduce at an amount that is appropriate for its particular niche.

These factors, in conjunction with gene flow and mutations can cause changes in the proportion of different alleles within the gene pool of a population. This shift in the frequency of alleles can lead to the emergence of novel traits and eventually new species over time.

Many of the features that we admire about animals and plants are adaptations, for example, the lungs or gills that extract oxygen from the air, fur or feathers for insulation, long legs for running away from predators and camouflage for hiding. However, a proper understanding of adaptation requires paying attention to the distinction between physiological and behavioral characteristics.

Physiological adaptations, such as thick fur or gills are physical traits, while behavioral adaptations, like the tendency to search for friends or to move to the shade during hot weather, are not. Additionally, it is important to remember that a lack of thought does not mean that something is an adaptation. In fact, failure to consider the consequences of a behavior can make it unadaptive even though it appears to be reasonable or even essential.

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