Are Free Evolution The Same As Everyone Says?
What is Free Evolution?
Free evolution is the concept that natural processes can cause organisms to evolve over time. This includes the evolution of new species and the alteration of the appearance of existing ones.
A variety of examples have been provided of this, including different varieties of fish called sticklebacks that can be found in salt or fresh water, and walking stick insect varieties that are attracted to specific host plants. These reversible traits cannot explain fundamental changes to the body's basic plans.
Evolution through Natural Selection
Scientists have been fascinated by the evolution of all the living creatures that inhabit our planet for centuries. The best-established explanation is that of Charles Darwin's natural selection process, which occurs when better-adapted individuals survive and reproduce more effectively than those who are less well-adapted. As time passes, the number of well-adapted individuals grows and eventually forms a new species.
Natural selection is an ongoing process that involves the interaction of three elements that are inheritance, variation and reproduction. Sexual reproduction and mutations increase the genetic diversity of an animal species. Inheritance is the transfer of a person's genetic traits to the offspring of that person that includes recessive and dominant alleles. Reproduction is the production of fertile, viable offspring which includes both asexual and sexual methods.
All of these factors must be in harmony for natural selection to occur. For instance when the dominant allele of a gene causes an organism to survive and reproduce more often than the recessive allele the dominant allele will be more prominent in the population. If the allele confers a negative advantage to survival or lowers the fertility of the population, it will be eliminated. This 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 more offspring an organism can produce, the greater its fitness, which is measured by its capacity to reproduce itself and survive. Individuals with favorable traits, such as having a longer neck in giraffes or bright white color patterns in male peacocks are more likely survive and have offspring, so they will make up the majority of the population in the future.
Natural selection is an aspect of populations and not on individuals. This is a significant distinction from the Lamarckian theory of evolution, which argues that animals acquire characteristics by use or inactivity. If a giraffe stretches its neck to reach prey and its neck gets longer, then the children will inherit this characteristic. The difference in neck size between generations will continue to increase until the giraffe becomes unable to reproduce with other giraffes.
Evolution by Genetic Drift
Genetic drift occurs when alleles from one gene are distributed randomly in a population. In 에볼루션 블랙잭 , one will reach fixation (become so common that it is unable to be eliminated through natural selection), while the other alleles drop to lower frequency. In the extreme, this leads to one allele dominance. The other alleles are eliminated, and heterozygosity is reduced to zero. In a small group, this could result in the complete elimination the recessive gene. Such a scenario would be known as a bottleneck effect and it is typical of evolutionary process that takes place when a large amount of people migrate to form a new population.
A phenotypic bottleneck can also occur when the survivors of a catastrophe like an outbreak or a mass hunting event are concentrated in the same area. The survivors will have an allele that is dominant and will have the same phenotype. This could be caused by war, an earthquake or even a disease. Regardless of the cause the genetically distinct group that remains is prone to genetic drift.
Walsh, Lewens, and Ariew utilize Lewens, Walsh, and Ariew use a "purely outcome-oriented" definition of drift as any deviation from the expected values of differences in fitness. They cite the famous example of twins who are both genetically identical and share the same phenotype. However, one is struck by lightning and dies, while the other lives to reproduce.
This kind of drift could play a very important role in the evolution of an organism. But, it's not the only method to develop. Natural selection is the primary alternative, in which mutations and migration maintain the phenotypic diversity of a population.
Stephens claims that there is a big difference between treating the phenomenon of drift as a force, or a cause and considering other causes of evolution, such as selection, mutation, and migration as forces or causes. Stephens claims that a causal process explanation of drift lets us distinguish it from other forces, and this differentiation is crucial. He also argues that drift is both direction, i.e., it tends towards eliminating heterozygosity. It also has a size, which is determined based on population size.
Evolution by Lamarckism
Biology students in high school are often introduced to Jean-Baptiste Lemarck's (1744-1829) work. His theory of evolution is commonly called "Lamarckism" and it asserts that simple organisms evolve into more complex organisms via the inheritance of traits that are a result of the organism's natural actions usage, use and disuse. Lamarckism is usually illustrated with a picture of a giraffe stretching its neck longer to reach higher up in the trees. This would cause giraffes to pass on their longer necks to offspring, who would then grow even taller.
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 previous thinking on organic transformation. According Lamarck, living organisms evolved from inanimate material by a series of gradual steps. Lamarck was not the first to propose this, but he was widely considered to be the first to offer the subject a comprehensive and general explanation.
The prevailing story is that Lamarckism grew into a rival to Charles Darwin's theory of evolution by natural selection, and both theories battled each other in the 19th century. Darwinism eventually triumphed and led to the development of what biologists today refer to as the Modern Synthesis. The theory denies that acquired characteristics are passed down from generation to generation and instead argues organisms evolve by the selective influence of environmental factors, such as Natural Selection.
Although Lamarck endorsed the idea of inheritance by acquired characters, and his contemporaries also offered a few words about this idea but it was not a major feature in any of their evolutionary theories. This is due to the fact that it was never tested scientifically.
It's been more than 200 years since Lamarck was born and, in the age of genomics, there is a large amount of evidence to support the heritability of acquired traits. This is also known as "neo Lamarckism", or more generally epigenetic inheritance. It is a version of evolution that is as valid as the more popular Neo-Darwinian theory.
Evolution by the process of adaptation
One of the most popular 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 is more accurately described as a struggle to survive in a specific environment. This may include not just other organisms but also the physical environment.
To understand how evolution functions it is beneficial to consider what adaptation is. It refers to a specific feature that allows an organism to live and reproduce within its environment. It could be a physiological structure like feathers or fur, or a behavioral trait, such as moving into the shade in the heat or leaving at night to avoid cold.
The ability of an organism to draw energy from its environment and interact with other organisms, as well as their physical environment, is crucial to its survival. The organism must have the right genes to produce offspring and be able find enough food and resources. The organism should also be able to reproduce at a rate that is optimal for its particular niche.
These factors, along with gene flow and mutation result in a change in the proportion of alleles (different varieties of a particular gene) in the gene pool of a population. This change in allele frequency can lead to the emergence of new traits, and eventually new species in the course of time.
Many of the features that we admire in animals and plants are adaptations, for example, lungs or gills to extract oxygen from the air, fur or feathers to provide insulation long legs to run away from predators, and camouflage to hide. However, a thorough understanding of adaptation requires a keen eye to the distinction between the physiological and behavioral characteristics.
Physical characteristics like thick fur and gills are physical traits. Behavior adaptations aren't, such as the tendency of animals to seek companionship or to retreat into the shade in hot temperatures. It is also important to remember that a insufficient planning does not cause an adaptation. Inability to think about the consequences of a decision, even if it appears to be rational, could make it inflexible.