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What is Free Evolution?

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

This is evident in many examples of stickleback fish species that can live in saltwater or fresh water and walking stick insect varieties that are apprehensive about specific host plants. These reversible traits however, are not able to explain fundamental changes in basic body plans.

Evolution by Natural Selection

The development of the myriad living organisms on Earth is an enigma that has fascinated scientists for centuries. The most well-known explanation is that of Charles Darwin's natural selection process, 에볼루션 코리아 a process that is triggered when more well-adapted individuals live longer and 에볼루션 reproduce more effectively than those less well adapted. Over time, a community of well-adapted individuals increases and eventually becomes a new species.

Natural selection is an ongoing process that involves the interaction of three elements including inheritance, variation, and reproduction. Mutation and sexual reproduction increase the genetic diversity of a 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 process of creating viable, fertile offspring. This can be done by both asexual or sexual methods.

All of these elements have to be in equilibrium to allow natural selection to take place. For example the case where the dominant allele of one gene allows an organism to live and reproduce more often than the recessive one, the dominant allele will be more prominent within the population. If the allele confers a negative advantage to survival or lowers the fertility of the population, it will disappear. This process is self-reinforcing meaning that a species with a beneficial trait is more likely to survive and reproduce than one with a maladaptive trait. The higher the level of fitness an organism has which is measured by its ability to reproduce and survive, is the greater number of offspring it will produce. People with good characteristics, such as a long neck in giraffes, or bright white color patterns on male peacocks are more likely to others to survive and reproduce which eventually leads to them becoming the majority.

Natural selection only acts on populations, not on individuals. This is a major distinction from the Lamarckian theory of evolution which argues that animals acquire traits through use or disuse. For instance, if a giraffe's neck gets longer through reaching out to catch prey its offspring will inherit a longer neck. The differences in neck length between generations will persist until the giraffe's neck becomes too long to not breed with other giraffes.

Evolution through Genetic Drift

In the process of genetic drift, alleles within a gene can be at different frequencies within a population through random events. Eventually, one of them will attain fixation (become so common that it can no longer be eliminated through natural selection), while other alleles fall to lower frequencies. This could lead to a dominant allele in the extreme. Other alleles have been basically eliminated and heterozygosity has been reduced to zero. In a small group this could lead to the complete elimination the recessive gene. Such a scenario would be called a bottleneck effect, and it is typical of the kind of evolutionary process that occurs when a lot of people migrate to form a new population.

A phenotypic bottleneck could happen when the survivors of a catastrophe such as an epidemic or mass hunting event, are concentrated in a limited area. The survivors will share an allele that is dominant and will share the same phenotype. This situation could be caused by war, earthquakes or even a plague. The genetically distinct population, if left vulnerable to genetic drift.

Walsh Lewens, 에볼루션 슬롯게임 룰렛 (0lq70Ey8Yz1b.com) Lewens, and Ariew use Lewens, Walsh and Ariew employ a "purely outcome-oriented" definition of drift as any deviation from expected values for different fitness levels. They give a famous instance of twins who are genetically identical, have the exact same phenotype but one is struck by lightning and dies, whereas the other lives and reproduces.

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

Stephens argues there is a huge difference between treating the phenomenon of drift as an agent or cause and considering other causes, such as migration and selection mutation as causes and forces. 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 has a direction, that is it tends to reduce heterozygosity, and that it also has a size, that is determined by the size of the population.

Evolution by Lamarckism

When students in high school study biology they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, often called "Lamarckism, states that simple organisms develop into more complex organisms by taking on traits that result from an organism's use and disuse. Lamarckism can be demonstrated by a giraffe extending its neck to reach higher leaves in the trees. This could cause giraffes to pass on their longer necks to their offspring, who then get taller.

Lamarck the French zoologist, presented an innovative idea in his 17 May 1802 opening lecture at the Museum of Natural History of Paris. He challenged the conventional wisdom on organic transformation. According to Lamarck, living creatures evolved from inanimate matter through a series of gradual steps. Lamarck was not the first to suggest that this could be the case but the general consensus is that he was the one being the one who gave the subject his first comprehensive and comprehensive analysis.

The dominant story is that Charles Darwin's theory on evolution by natural selection and Lamarckism were competing in the 19th Century. Darwinism eventually won, leading to the development of what biologists now refer to as the Modern Synthesis. The Modern Synthesis theory denies the possibility that acquired traits can be acquired through inheritance and instead suggests that organisms evolve through the action of environmental factors, such as natural selection.

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

But it is now more than 200 years since Lamarck was born and in the age genomics there is a vast amount of evidence to support the possibility of inheritance of acquired traits. This is also known as "neo Lamarckism", or more generally epigenetic inheritance. It is a variant of evolution that is as valid as the more well-known Neo-Darwinian model.

Evolution through the process of adaptation

One of the most widespread misconceptions about evolution is that it is driven by a sort of struggle to survive. In fact, this view is inaccurate and overlooks the other forces that determine the rate of evolution. The fight for survival can be better described as a fight to survive in a certain 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 survive in its environment and reproduce. It could be a physiological structure, such as feathers or fur or a behavior, such as moving into shade in the heat or leaving at night to avoid cold.

An organism's survival depends on its ability to draw energy from the environment and to interact with other organisms and their physical environments. The organism should possess the right genes to create offspring and be able find sufficient food and resources. Moreover, the organism must be able to reproduce itself at a high rate within its environmental niche.

These elements, along with gene flow and mutations can cause changes in the proportion of different alleles within 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 animals and plants are adaptations. For example, lungs or gills that extract oxygen from the air feathers and fur for insulation, long legs to run away from predators, and camouflage to hide. To understand the concept of adaptation it is crucial to distinguish between behavioral and physiological characteristics.

Physiological adaptations like thick fur or gills, are physical traits, whereas behavioral adaptations, like the tendency to seek out companions or to move to the shade during hot weather, are not. It is also important to note that the absence of planning doesn't cause an adaptation. In fact, failure to think about the implications of a behavior can make it unadaptive despite the fact that it might appear logical or even necessary.