• 목록
• 답변
• 글쓰기
• 게시판 리스트 옵션
  • 수정
  • 삭제

What is Free Evolution?

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

Numerous examples have been offered of this, such as different varieties of fish called sticklebacks that can be found in fresh or salt water and walking stick insect varieties that favor particular host plants. These mostly reversible trait permutations, however, cannot explain fundamental changes in body plans.

Evolution through Natural Selection

The development of the myriad of living organisms on Earth is a mystery that has fascinated scientists for decades. Charles Darwin's natural selection theory is the best-established explanation. This happens when those who are better adapted are able to reproduce faster and longer than those who are less well-adapted. Over time, a population of well-adapted individuals increases and eventually forms a whole new species.

Natural selection is a cyclical process that is characterized by the interaction of three factors that are inheritance, variation and reproduction. Variation is caused by mutation and sexual reproduction both of which increase the genetic diversity within a species. Inheritance is the term used to describe the transmission of a person’s genetic traits, which include recessive and dominant genes, to their offspring. Reproduction is the process of generating viable, fertile offspring. This can be achieved through sexual or asexual methods.

Natural selection is only possible when all these elements are in harmony. If, for example an allele of a dominant gene makes an organism reproduce and survive more than the recessive allele then the dominant allele will become more common in a population. If the allele confers a negative advantage to survival or lowers the fertility of the population, it will disappear. The process is self-reinforcing, meaning that a species with a beneficial characteristic is more likely to survive and reproduce than an individual with an inadaptive characteristic. The greater an organism's fitness as measured by its capacity to reproduce and endure, is the higher number of offspring it produces. Individuals with favorable traits, like a longer neck in giraffes and 에볼루션 bright white color patterns in male peacocks, are more likely to survive and have offspring, and thus will make up the majority of the population over time.

Natural selection only acts on populations, not individual organisms. This is an important distinction from the Lamarckian theory of evolution which claims that animals acquire traits through use or neglect. If a giraffe expands its neck in order to catch prey, and the neck becomes longer, then the offspring will inherit this trait. The difference in neck size between generations will continue to grow until the giraffe becomes unable to reproduce with other giraffes.

Evolution by Genetic Drift

In the process of genetic drift, alleles of a gene could attain different frequencies in a group by chance events. Eventually, one of them will reach fixation (become so common that it cannot be removed through natural selection), while the other alleles drop to lower frequencies. In extreme cases this, 에볼루션 바카라 사이트 it leads to one allele dominance. The other alleles are essentially eliminated, and heterozygosity decreases to zero. In a small number of people, 에볼루션 바카라사이트 this could result in the complete elimination of recessive gene. This scenario is called a bottleneck effect, and it is typical of evolutionary process when a large number of individuals migrate to form a new population.

A phenotypic 'bottleneck' can also occur when the survivors of a catastrophe such as an outbreak or mass hunting event are concentrated in a small area. The surviving individuals are likely to be homozygous for the dominant allele, which means they will all have the same phenotype, and thus have the same fitness traits. This situation might be caused by a war, earthquake or even a cholera outbreak. 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 deviation from expected values due to differences in fitness. They give a famous example of twins that are genetically identical, share identical phenotypes but one is struck by lightning and dies, whereas the other lives and reproduces.

This kind of drift could be crucial in the evolution of an entire species. However, it's not the only way to evolve. Natural selection is the main alternative, where mutations and migration keep phenotypic diversity within the population.

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

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 is often called "Lamarckism" and it asserts that simple organisms evolve into more complex organisms through the inherited characteristics that result from the natural activities of an organism use and misuse. Lamarckism can be illustrated by a giraffe extending its neck to reach higher leaves in the trees. This would cause the necks of giraffes that are longer to be passed onto their offspring who would 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 the 17th May 1802, he presented an original idea that fundamentally challenged the previous understanding of organic transformation. According to him living things evolved from inanimate matter through the gradual progression of events. Lamarck was not the first to suggest that this could be the case but his reputation is widely regarded as being the one who gave the subject its first general and comprehensive analysis.

The most popular story is that Charles Darwin's theory on natural selection and Lamarckism were competing during the 19th century. Darwinism ultimately prevailed which led to what biologists refer to as the Modern Synthesis. This theory denies acquired characteristics can be passed down through generations and instead argues organisms evolve by the influence of environment factors, such as Natural Selection.

Although Lamarck believed in the concept of inheritance through acquired characters and his contemporaries paid lip-service to this notion but it was not an integral part of any of their evolutionary theories. This is due in part to the fact that it was never tested scientifically.

However, it has been more than 200 years since Lamarck was born and in the age genomics, there is a large amount of evidence that supports the heritability of acquired traits. This is also referred to as "neo Lamarckism", or more often epigenetic inheritance. It is a version of evolution that is just as valid as the more well-known Neo-Darwinian model.

Evolution by adaptation

One of the most common misconceptions about evolution is that it is driven by a type of struggle for survival. This view is inaccurate and overlooks other forces that drive evolution. The struggle for survival is more accurately described as a struggle to survive in a specific environment, which can involve not only other organisms, but as well the physical environment.

Understanding adaptation is important to understand evolution. It is a feature that allows a living thing to survive in its environment and reproduce. It can be a physiological structure, like feathers or fur or a behavioral characteristic like moving into shade in hot weather or coming out at night to avoid cold.

The capacity of a living thing to extract energy from its surroundings and interact with other organisms as well as their physical environments is essential to its survival. The organism needs to have the right genes to generate offspring, and must be able to access sufficient food and other resources. In addition, 에볼루션 슬롯게임 the organism should be capable of reproducing itself at an optimal rate within its environment.

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. Over time, this change in allele frequencies could lead to the emergence of new traits and ultimately new species.

Many of the characteristics we admire about animals and plants are adaptations, like lung or gills for removing oxygen from the air, fur or feathers to provide insulation, long legs for running away from predators, and camouflage for hiding. However, a complete understanding of adaptation requires paying attention to the distinction between behavioral and physiological traits.

Physical characteristics like thick fur and gills are physical characteristics. The behavioral adaptations aren't an exception, for instance, the tendency of animals to seek out companionship or to retreat into the shade during hot temperatures. Furthermore it is important to remember that lack of planning does not make something an adaptation. A failure to consider the consequences of a decision even if it seems to be rational, could make it unadaptive.