What is Free Evolution?

Free evolution is the notion that natural processes can cause organisms to evolve over time. This includes the evolution of new species and transformation of the appearance of existing ones.

Many examples have been given of this, such as different kinds of stickleback fish that can be found in salt or fresh water, and walking stick insect varieties that favor specific host plants. These mostly reversible trait permutations however, are not able to be the reason for fundamental changes in body plans.

Evolution by Natural Selection

The development of the myriad of living creatures on Earth is a mystery that has intrigued scientists for decades. Charles Darwin's natural selection theory is the most well-known explanation. This process occurs when those who are better adapted have more success in reproduction and survival than those who are less well-adapted. As time passes, a group of well-adapted individuals expands and eventually forms a whole new species.

Natural selection is an ongoing process that is characterized by the interaction of three elements: variation, inheritance and reproduction. Variation is caused by mutations and sexual reproduction both of which increase the genetic diversity within an animal species. Inheritance refers the transmission of a person's genetic traits, including recessive and dominant genes to their offspring. Reproduction is the generation of fertile, viable offspring which includes both asexual and sexual methods.

All of these factors must be in balance to allow natural selection to take place. For instance when the dominant allele of one gene allows an organism to live and reproduce more often than the recessive allele the dominant allele will be more common in the population. If the allele confers a negative survival advantage or decreases the fertility of the population, it will go away. The process is self-reinforced, meaning that an organism with a beneficial characteristic is more likely to survive and reproduce than an individual with a maladaptive trait. The more fit an organism is as measured by its capacity to reproduce and survive, is the greater number of offspring it will produce. Individuals with favorable characteristics, such as the long neck of the giraffe, or bright white color patterns on male peacocks are more likely than others to live and reproduce and 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, 에볼루션 which states that animals acquire characteristics through use or disuse. If a giraffe stretches its neck in order to catch prey, and the neck becomes larger, then its offspring will inherit this characteristic. The length difference between generations will persist until the neck of the giraffe becomes so long that it can not breed with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles of a gene are randomly distributed in a group. In the end, one will reach fixation (become so widespread that it is unable to be eliminated through natural selection), while other alleles will fall to lower frequencies. In the extreme this, it leads to dominance of a single allele. Other alleles have been basically eliminated and heterozygosity has diminished to a minimum. In a small population, this could result in the complete elimination the recessive gene. This scenario is called the bottleneck effect and is typical of the evolutionary process that occurs whenever 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 a massive hunting event, are condensed within a narrow area. The survivors will have an allele that is dominant and will have the same phenotype. This may be the result of a conflict, earthquake or even a cholera outbreak. Whatever the reason, the genetically distinct population that remains could be susceptible to genetic drift.

Walsh, Lewens, and Ariew employ Lewens, Walsh, and Ariew use a "purely outcome-oriented" definition of drift as any departure from the expected values for different fitness levels. They cite the famous example of twins who are genetically identical and have exactly the same phenotype, but one is struck by lightning and 에볼루션사이트 dies, but the other is able to reproduce.

This type of drift can play a very important role in the evolution of an organism. But, it's not the only way to progress. The primary alternative is a process called natural selection, in which the phenotypic variation of a population is maintained by mutation and migration.

Stephens argues that there is a major difference between treating drift as a force or a cause and treating other causes of evolution like mutation, selection and migration as causes or causes. He claims that a causal process explanation of drift allows us to distinguish it from the other forces, 무료에볼루션 게이밍 (relevant webpage) and this distinction is essential. He also argues that drift is both a direction, i.e., 에볼루션 바카라 무료체험 it tends to reduce heterozygosity. It also has a size which is determined by population size.

Evolution by Lamarckism

In high school, students study biology they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution is commonly referred to as "Lamarckism" and it states that simple organisms grow into more complex organisms through the inheritance of characteristics which result from the organism's natural actions, use and disuse. Lamarckism is typically illustrated with the image of a giraffe stretching its neck to reach the higher branches in the trees. This could cause giraffes to pass on their longer necks to their offspring, which then get taller.

Lamarck Lamarck, a French zoologist, presented a revolutionary concept in his 17 May 1802 opening lecture at the Museum of Natural History of Paris. He challenged the traditional thinking about organic transformation. According Lamarck, living organisms evolved from inanimate material through a series of gradual steps. Lamarck was not the first to make this claim but he was considered to be the first to offer the subject a comprehensive and general explanation.

The most popular story is that Lamarckism grew into an opponent to Charles Darwin's theory of evolution by natural selection and both theories battled out in the 19th century. Darwinism eventually prevailed and led to the development of what biologists now refer to as the Modern Synthesis. The Modern Synthesis theory denies that traits acquired through evolution can be inherited, and instead suggests that organisms evolve through the action of environmental factors, including natural selection.

Lamarck and his contemporaries believed in the notion that acquired characters could be passed on to future generations. However, this notion was never a central part of any of their theories about evolution. This is due to the fact that it was never scientifically validated.

It's been more than 200 years since Lamarck was born and in the age of genomics there is a huge body of evidence supporting the heritability of acquired characteristics. This is often referred to as "neo-Lamarckism" or more often epigenetic inheritance. It is a version of evolution that is as relevant as the more popular Neo-Darwinian theory.

Evolution by the process of adaptation

One of the most widespread misconceptions about evolution is that it is driven by a sort of struggle for survival. This notion is not true and ignores other forces driving evolution. The fight for survival can be more effectively described as a struggle to survive in a specific environment, which can involve not only other organisms, but also the physical environment.

To understand how evolution operates it is important to consider what adaptation is. The term "adaptation" refers to any specific feature that allows an organism to survive and reproduce in its environment. It can be a physiological feature, such as fur or feathers, or a behavioral trait like moving into shade in the heat or leaving at night to avoid the cold.

The ability 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 must have the right genes to produce offspring and be able find enough food and resources. Furthermore, the organism needs to be capable of reproducing itself in a way that is optimally within its environmental niche.

These factors, along with mutation and gene flow, lead to 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 result in the development of new traits and ultimately new species.

Many of the characteristics we admire about animals and plants are adaptations, such as the lungs or gills that extract oxygen from the air, fur or feathers to protect themselves long legs to run away from predators, and camouflage for hiding. To understand the concept of adaptation it is crucial to distinguish between behavioral and physiological characteristics.

Physical traits such as large gills and thick fur are physical characteristics. The behavioral adaptations aren't an exception, for instance, the tendency of animals to seek out companionship or retreat into shade in hot weather. It is also important to keep in mind that the absence of planning doesn't result in an adaptation. A failure to consider the implications of a choice, even if it appears to be rational, may cause it to be unadaptive.