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What is Free Evolution?

Free evolution is the notion that natural processes can cause organisms to evolve over time. This includes the creation of new species as well as the change in appearance of existing species.

Many examples have been given of this, including various kinds of stickleback fish that can live in either salt or fresh water, as well as walking stick insect varieties that are attracted to particular host plants. These are mostly reversible traits, however, cannot explain fundamental changes in body plans.

Evolution by Natural Selection

The development of the myriad living creatures on Earth is an enigma that has fascinated scientists for centuries. The best-established explanation is that of Charles Darwin's natural selection, an evolutionary process that occurs when individuals that are better adapted survive and reproduce more successfully than those that are less well adapted. Over time, the population of individuals who are well-adapted grows and eventually creates an entirely new species.

Natural selection is an ongoing process that involves the interaction of three factors including inheritance, variation, and reproduction. Variation is caused by mutation and sexual reproduction both of which increase the genetic diversity of the species. Inheritance refers to the transmission of genetic traits, which include both dominant and recessive genes to their offspring. Reproduction is the production of fertile, viable offspring, which includes both sexual and asexual methods.

All of these variables must be in balance for natural selection to occur. For example the case where an allele that is dominant at the gene causes an organism to survive and reproduce more often than the recessive one, the dominant allele will be more prominent in the population. However, if the allele confers a disadvantage in survival or decreases fertility, it will disappear from the population. This process is self-reinforcing meaning that an organism with a beneficial trait will survive and reproduce more than an individual with a maladaptive trait. The more offspring an organism produces the better its fitness that is determined by its capacity to reproduce itself and live. People with good characteristics, such as a long neck in the giraffe, or bright white patterns on male peacocks, are more likely than others to live and reproduce which eventually leads to them becoming the majority.

Natural selection only acts on populations, not individuals. This is a significant distinction from the Lamarckian theory of evolution which holds that animals acquire traits due to the use or absence of use. If a giraffe stretches its neck to reach prey, and the neck becomes longer, then the offspring will inherit this trait. The differences in neck size between generations will increase until the giraffe is unable to reproduce with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles from a gene are randomly distributed within a population. At some point, 에볼루션 코리아 only one of them will be fixed (become common enough that it can no longer be eliminated by natural selection), and the other alleles drop in frequency. In extreme cases this, it leads to dominance of a single allele. The other alleles are essentially eliminated, and heterozygosity is reduced to zero. In a small population it could lead to the total elimination of the recessive allele. This is known as the bottleneck effect and is typical of an evolution process that occurs when an enormous number of individuals move to form a population.

A phenotypic bottleneck may occur when the survivors of a disaster such as an epidemic or 에볼루션바카라 a mass hunt, are confined within a narrow area. The survivors will have an allele that is dominant and will share the same phenotype. This could be caused by earthquakes, war, or even plagues. The genetically distinct population, if left, could be susceptible to genetic drift.

Walsh, Lewens, and Ariew use a "purely outcome-oriented" definition of drift as any deviation from the expected values of variations in fitness. They cite a famous example of twins that are genetically identical, have identical phenotypes and yet one is struck by lightning and dies, whereas the other lives and reproduces.

This kind of drift could play a very important role in the evolution of an organism. But, 에볼루션 룰렛 it's not the only way to progress. The most common alternative is a process called natural selection, where phenotypic variation in the population is maintained through mutation and migration.

Stephens asserts that there is a significant difference between treating the phenomenon of drift as a force or as a cause and considering other causes of evolution such as selection, mutation, and migration as forces or causes. He argues that a causal-process explanation of drift lets us distinguish it from other forces and that this differentiation is crucial. He further argues that drift has both direction, i.e., it tends towards eliminating heterozygosity. It also has a size, that is determined by population size.

Evolution through Lamarckism

Students of biology in high school are often introduced to Jean-Baptiste Lamarck's (1744-1829) work. His theory of evolution is generally called "Lamarckism" and it asserts that simple organisms evolve into more complex organisms by the inherited characteristics that are a result of an organism's natural activities, use and disuse. Lamarckism can be demonstrated by an giraffe's neck stretching to reach higher levels of leaves in the trees. This would cause giraffes to pass on their longer necks to their offspring, who would then get taller.

Lamarck, a French zoologist, presented an idea that was revolutionary in his opening lecture at the Museum of Natural History of Paris. He challenged the previous thinking on organic transformation. According to him living things evolved from inanimate matter via a series of gradual steps. Lamarck wasn't the first to propose this but he was considered to be the first to provide the subject a thorough and general overview.

The dominant story is that Charles Darwin's theory on evolution by natural selection and Lamarckism were rivals during the 19th century. Darwinism eventually prevailed, leading to what biologists call the Modern Synthesis. The theory argues that acquired traits can be passed down and instead argues that organisms evolve through the selective influence of environmental factors, including Natural Selection.

Although Lamarck believed in the concept of inheritance through acquired characters, and his contemporaries also offered a few words about this idea however, it was not an integral part of any of their evolutionary theories. This is due in part to the fact that it was never validated scientifically.

But it is now more than 200 years since Lamarck was born and in the age genomics there is a vast body of evidence supporting the heritability of acquired characteristics. This is also known as "neo Lamarckism", or more commonly epigenetic inheritance. It is a variant of evolution that is as relevant as the more popular neo-Darwinian model.

Evolution through adaptation

One of the most commonly-held misconceptions about evolution is that it is being driven by a struggle to survive. This view is inaccurate and overlooks other forces that drive evolution. The fight for survival can be more effectively described as a struggle to survive within a particular environment, which can involve not only other organisms, but also the physical environment itself.

To understand how evolution functions it is beneficial to consider what adaptation is. The term "adaptation" refers to any specific characteristic that allows an organism to live and reproduce within its environment. It could be a physical structure, such as feathers or fur. Or it can be a behavior trait such as moving into the shade during the heat, or coming out to avoid the cold at night.

The capacity of an organism to draw energy from its environment and interact with other organisms and their physical environments is essential to its survival. The organism must possess the right genes to create offspring and be able find sufficient food and resources. Furthermore, the organism needs to be able to reproduce itself at a high rate within its environmental niche.

These factors, together with mutations and gene flow can cause a shift in the proportion of different alleles in a population’s gene pool. This change in allele frequency can lead to the emergence of new traits and eventually new species over time.

A lot of the traits we admire in animals and plants are adaptations, for example, lungs or gills to extract oxygen from the air, feathers or 에볼루션바카라 fur to protect themselves and long legs for running away from predators and camouflage for hiding. However, a thorough understanding of adaptation requires attention to the distinction between behavioral and physiological characteristics.

Physiological adaptations, like thick fur or 에볼루션 코리아 gills are physical traits, whereas behavioral adaptations, like the desire to find companions or to move to the shade during hot weather, 에볼루션 바카라 무료체험 aren't. It is also important to keep in mind that lack of planning does not result in an adaptation. A failure to consider the consequences of a decision, even if it appears to be logical, can cause it to be unadaptive.