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What is Free Evolution?

Free evolution is the idea that the natural processes that organisms go through can lead them to evolve over time. This includes the creation of new species and change in appearance of existing species.

Many examples have been given of this, such as different kinds of stickleback fish that can live in either fresh or salt water and walking stick insect varieties that prefer particular host plants. These mostly reversible trait permutations can't, however, explain fundamental changes in basic body plans.

Evolution by Natural Selection

The evolution of the myriad living organisms on Earth is a mystery that has intrigued scientists for centuries. The most well-known explanation is Charles Darwin's natural selection, which occurs when individuals that are better adapted survive and reproduce more effectively than those that are 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 three factors that are: reproduction, variation and inheritance. Sexual reproduction and mutations increase genetic diversity in a species. Inheritance refers to the transmission of genetic characteristics, which includes recessive and dominant genes and their offspring. Reproduction is the generation of viable, fertile offspring, which includes both asexual and sexual methods.

Natural selection only occurs when all the factors are in harmony. For instance when an allele that is dominant at the gene allows an organism to live and reproduce more frequently than the recessive allele, the dominant allele will become more common within the population. If the allele confers a negative advantage to survival or reduces the fertility of the population, it will be eliminated. The process is self-reinforcing which means that an organism that has an adaptive characteristic will live and reproduce more quickly than those with a maladaptive trait. The greater an organism's fitness as measured by its capacity to reproduce and survive, is the greater number of offspring it produces. People with good traits, like having a long neck in giraffes, or bright white patterns on male peacocks, are more likely than others to reproduce and survive, 에볼루션 룰렛 which will eventually lead to them becoming the majority.

Natural selection is only a factor in populations and not on individuals. This is a major distinction from the Lamarckian theory of evolution, which argues that animals acquire characteristics through use or disuse. For example, if a giraffe's neck gets longer through reaching out to catch prey its offspring will inherit a longer neck. The differences in neck size between generations will increase until the giraffe becomes unable to reproduce with other giraffes.

Evolution by Genetic Drift

In genetic drift, alleles within a gene can reach different frequencies in a population through random events. In the end, one will attain fixation (become so widespread that it can no longer be removed by natural selection), while other alleles fall to lower frequency. In extreme cases this, it leads to a single allele dominance. Other alleles have been essentially eliminated and heterozygosity has been reduced to a minimum. In a small population this could lead to the complete elimination of recessive gene. This scenario is known as a bottleneck effect and it is typical of evolutionary process when a large number of individuals move to form a new group.

A phenotypic bottleneck may happen when the survivors of a disaster, such as an epidemic or a mass hunting event, are concentrated into a small area. The remaining individuals will be mostly homozygous for the dominant allele, meaning that they all share the same phenotype and therefore have the same fitness traits. This could be caused by earthquakes, war or even a plague. The genetically distinct population, if it is left, could be susceptible to genetic drift.

Walsh Lewens, Walsh, and Ariew define drift as a deviation from expected values due to differences in fitness. They give a famous instance of twins who are genetically identical, share identical phenotypes, and yet one is struck by lightening and dies while the other lives and reproduces.

This type of drift is crucial in the evolution of a species. However, it's not the only way to evolve. Natural selection is the main alternative, in which mutations and migrations maintain the phenotypic diversity of the population.

Stephens argues that there is a significant difference between treating the phenomenon of drift as a force or an underlying cause, and treating other causes of evolution such as selection, mutation and migration as forces or causes. He argues that a causal process explanation of drift permits us to differentiate it from other forces, and this distinction is crucial. He further argues that drift has a direction: that is it tends to eliminate heterozygosity. It also has a size, which is determined by the size of the population.

Evolution by Lamarckism

When high school students study biology, they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution is generally known as "Lamarckism" and it states that simple organisms grow into more complex organisms through the inheritance of characteristics which result from an organism's natural activities usage, use and disuse. Lamarckism can be illustrated by a giraffe extending its neck to reach higher leaves in the trees. This would result in giraffes passing on their longer necks to offspring, who then become taller.

Lamarck Lamarck, a French Zoologist, introduced an innovative idea 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 had evolved from inanimate matter through the gradual progression of events. Lamarck wasn't the only one to propose this however he was widely regarded as the first to provide the subject a comprehensive and general overview.

The predominant story is that Charles Darwin's theory of natural selection and Lamarckism were rivals in the 19th Century. Darwinism eventually triumphed and led to the creation of what biologists now call the Modern Synthesis. The theory denies that acquired characteristics can be passed down and instead argues organisms evolve by the selective influence of environmental factors, such as Natural Selection.

Lamarck and his contemporaries supported the idea that acquired characters could be passed on to future generations. However, this concept was never a key element of any of their theories about evolution. This is partly because it was never tested scientifically.

It's been more than 200 year since Lamarck's birth, and 에볼루션 바카라사이트 in the age genomics, there is a growing evidence base that supports the heritability of acquired traits. This is sometimes referred to as "neo-Lamarckism" or more often, epigenetic inheritance. It is a version of evolution that is as valid as the more well-known Neo-Darwinian theory.

Evolution by adaptation

One of the most common misconceptions about evolution is that it is a result of a kind of struggle to survive. This view is inaccurate and overlooks the other forces that drive evolution. The fight for survival can be more precisely described as a fight to survive in a specific environment, which can involve not only other organisms, but also the physical environment.

To understand how evolution functions it is beneficial to think about what adaptation is. Adaptation refers to any particular characteristic that allows an organism to live and reproduce within its environment. It can be a physical structure, such as feathers or fur. It could also be a trait of behavior such as moving into the shade during hot weather, or moving out to avoid the cold at night.

The ability of an organism to extract energy from its surroundings and interact with other organisms and their physical environment is essential to its survival. The organism must have the right genes to produce offspring, and be able to find enough food and resources. Furthermore, the organism needs to be capable of reproducing itself in a way that is optimally within its environment.

These factors, in conjunction with gene flow and mutations can result in a shift in the proportion of different alleles within a population’s gene pool. The change in frequency of alleles can lead to the emergence of new traits and eventually, new species as time passes.

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, 에볼루션 무료체험바카라 (www.modelbouwforum.nl) feathers or fur to provide insulation, 무료 에볼루션코리아; your domain name, long legs for running away from predators, and camouflage for hiding. However, a thorough understanding of adaptation requires attention to the distinction between physiological and behavioral traits.

Physical characteristics like thick fur and gills are physical traits. Behavior adaptations aren't like the tendency of animals to seek companionship or to retreat into the shade in hot weather. Additionally, it is important to remember that a lack of thought is not a reason to make something an adaptation. Failure to consider the consequences of a decision even if it seems to be rational, may cause it to be unadaptive.