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What Is Free Evolution? And How To Make Use Of It
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 appearance and development of new species.

This has been demonstrated by many examples such as the stickleback fish species that can thrive in saltwater or fresh water and walking stick insect types that prefer specific host plants. These reversible traits however, are not able to explain fundamental changes in body plans.

Evolution through Natural Selection

Scientists have been fascinated by the evolution of all living organisms that inhabit our planet for many centuries. Charles Darwin's natural selectivity is the best-established explanation. This process occurs when those who are better adapted are able to reproduce faster and longer than those who are less well-adapted. Over time, the population of well-adapted individuals becomes larger and eventually creates a new species.

Natural selection is a cyclical process that is characterized by the interaction of three elements: variation, inheritance and reproduction. 에볼루션 무료체험 and mutation increase genetic diversity in the species. Inheritance refers the transmission of a person’s genetic characteristics, which includes recessive and dominant genes, to their offspring. Reproduction is the process of generating fertile, viable offspring. This can be achieved by both asexual or sexual 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 frequently than the recessive one, the dominant allele will become more prevalent within the population. If the allele confers a negative survival advantage or decreases the fertility of the population, it will be eliminated. The process is self-reinforcing, which means that an organism with a beneficial trait can reproduce and survive longer than an individual with an inadaptive characteristic. The greater an organism's fitness, measured by its ability reproduce and survive, is the greater number of offspring it will produce. 에볼루션 바카라 무료체험 with favorable characteristics, such as having a long neck in the giraffe, or bright white patterns on male peacocks, are more likely than others to reproduce and survive, which will eventually lead to them becoming the majority.

Natural selection only affects populations, not individuals. This is a significant distinction from the Lamarckian theory of evolution, which argues that animals acquire characteristics by use or inactivity. For instance, if a animal's neck is lengthened by stretching to reach for prey, its offspring will inherit a more long neck. The difference in neck size between generations will continue to increase until the giraffe becomes unable to breed with other giraffes.

Evolution through Genetic Drift

Genetic drift occurs when the alleles of a gene are randomly distributed in a population. At some point, only one of them will be fixed (become common enough to no more be eliminated through natural selection) and the other alleles will diminish in frequency. This can result in dominance at the extreme. The other alleles are essentially eliminated, and heterozygosity is reduced to zero. In a small number of people this could result in the complete elimination of recessive allele. This scenario is called a bottleneck effect, and it is typical of evolutionary process that takes place when a large number of individuals migrate to form a new population.

A phenotypic 'bottleneck' can also occur when the survivors of a disaster such as an outbreak or mass hunting incident are concentrated in an area of a limited size. The surviving individuals are likely to be homozygous for the dominant allele, meaning that they all have the same phenotype and consequently have the same fitness traits. This could be caused by war, an earthquake or even a disease. Regardless of the cause the genetically distinct population that is left might be susceptible to genetic drift.

Walsh Lewens, Walsh, 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 share the same phenotype. However, one is struck by lightning and dies, but the other continues to reproduce.

This type of drift is vital to the evolution of the species. It is not the only method for evolution. The most common alternative is a process known as natural selection, in which phenotypic variation in a population is maintained by mutation and migration.

Stephens argues there is a significant distinction between treating drift as an agent or cause and considering other causes, such as selection mutation and migration as causes and forces. He claims that a causal mechanism account of drift allows us to distinguish it from other forces, and that this distinction is essential. He also claims that drift has a direction, that is it tends to reduce heterozygosity. It also has a size, which is determined by population size.

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, also referred to as "Lamarckism, states that simple organisms evolve into more complex organisms through inheriting characteristics that are a product of an organism's use and disuse. Lamarckism can be demonstrated by an giraffe's neck stretching to reach higher leaves in the trees. This could result in giraffes passing on their longer necks to offspring, who 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 17 May 1802, he introduced a groundbreaking concept that radically challenged the conventional wisdom about organic transformation. According Lamarck, living organisms evolved from inanimate materials by a series of gradual steps. Lamarck wasn't the only one to suggest this, but he was widely considered to be the first to give the subject a thorough and general explanation.

The predominant story is that Charles Darwin's theory on evolution by natural selection and Lamarckism were rivals in the 19th century. Darwinism eventually won and led to the creation of what biologists call the Modern Synthesis. The Modern Synthesis theory denies that traits acquired through evolution can be acquired through inheritance and instead argues that organisms evolve by the symbiosis of environmental factors, including natural selection.

Lamarck and his contemporaries supported the idea that acquired characters could be passed down to the next generation. However, this notion was never a major part of any of their theories on evolution. This is due in part to the fact that it was never validated scientifically.

It has been more than 200 years since the birth of Lamarck and in the field of age genomics there is a growing body of evidence that supports the heritability of acquired traits. This is also referred to as "neo Lamarckism", or more often epigenetic inheritance. This is a model that is just as valid as the popular neodarwinian model.

Evolution by Adaptation

One of the most common misconceptions about evolution is its being driven by a struggle for survival. In fact, this view is a misrepresentation of natural selection and ignores the other forces that are driving evolution. The fight for survival can be better described as a fight to survive in a specific environment. This can include not just other organisms but also the physical surroundings themselves.

Understanding adaptation is important to understand evolution. It refers to a specific characteristic that allows an organism to survive and reproduce in its environment. It can be a physiological structure, such as fur or feathers or a behavior like moving into shade in hot weather or coming out at night to avoid the cold.

The capacity of a living thing to extract energy from its surroundings and interact with other organisms and their physical environments is essential to its survival. The organism must possess the right genes for producing offspring, and be able to find sufficient food and resources. The organism must also be able reproduce at a rate that is optimal for its particular niche.

These factors, together with mutation and gene flow can result in a change in the proportion of alleles (different forms of a gene) in a population's gene pool. As time passes, this shift in allele frequencies could lead to the emergence of new traits, and eventually new species.

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

Physical characteristics like thick fur and gills are physical characteristics. Behavioral adaptations are not, such as the tendency of animals to seek out companionship or to retreat into the shade during hot temperatures. Additionally, it is important to understand that lack of planning does not make something an adaptation. Inability to think about the consequences of a decision even if it appears to be rational, could make it unadaptive.