What is Free Evolution?
Free evolution is the notion that the natural processes of living organisms can lead to their development over time. 에볼루션 바카라 무료 includes the appearance and growth of new species.
Numerous examples have been offered of this, including various varieties of fish called sticklebacks that can be found in salt or fresh water, as well as walking stick insect varieties that favor specific host plants. These mostly reversible trait permutations however, are not able to explain fundamental changes in basic body plans.
Evolution by Natural Selection
Scientists have been fascinated by the evolution of all living organisms that inhabit our planet for many centuries. Charles Darwin's natural selection is the most well-known explanation. This process occurs when people who are more well-adapted have more success in reproduction and survival than those who are less well-adapted. Over time, the population of individuals who are well-adapted grows and eventually develops into a new species.
Natural selection is an ongoing process and involves the interaction of 3 factors that are: reproduction, variation and inheritance. Variation is caused by mutations 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, including both dominant and recessive genes to their offspring. 에볼루션 코리아 is the process of producing viable, fertile offspring. This can be accomplished by both asexual or sexual methods.
All of these elements must be in harmony to allow natural selection to take place. If, for instance an allele of a dominant gene causes an organism reproduce and live longer than the recessive gene allele, then the dominant allele becomes more prevalent in a population. However, if the gene confers an unfavorable survival advantage or reduces fertility, it will be eliminated from the population. 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 greater an organism's fitness as measured by its capacity to reproduce and survive, is the greater number of offspring it produces. People with desirable characteristics, like longer necks in giraffes, or bright white patterns of color in male peacocks are more likely be able to survive and create offspring, and thus will eventually make up the majority of the population over time.
Natural selection only acts on populations, not individual organisms. This is a significant distinction from the Lamarckian theory of evolution which holds that animals acquire traits due to use or lack of use. If a giraffe stretches its neck to catch prey, and the neck becomes larger, then its offspring will inherit this trait. The length difference between generations will continue until the neck of the giraffe becomes so long that it can no longer breed with other giraffes.
Evolution by Genetic Drift
Genetic drift occurs when the alleles of the same gene are randomly distributed in a population. Eventually, only one will be fixed (become common enough that it can no more be eliminated through natural selection), and the other alleles will diminish in frequency. In the extreme this, it leads to one allele dominance. The other alleles are essentially eliminated, and heterozygosity falls to zero. In a small group, this could lead to the complete elimination of recessive allele. This scenario is called the bottleneck effect. It is typical of the evolutionary process that occurs whenever an enormous number of individuals move to form a population.
A phenotypic bottleneck can also occur when survivors of a catastrophe, such as an epidemic or a mass hunt, are confined in a limited area. The survivors will share an allele that is dominant and will have the same phenotype. This could be caused by earthquakes, war or even plagues. Regardless of the cause the genetically distinct group that remains could be susceptible to genetic drift.
Walsh Lewens, Walsh, and Ariew define drift as a departure from the expected values due to differences in fitness. They cite a famous example of twins that are genetically identical, have identical phenotypes but one is struck by lightning and dies, while the other lives and reproduces.
This type of drift can play a very important role in the evolution of an organism. It is not the only method of evolution. Natural selection is the primary alternative, in which mutations and migrations maintain the phenotypic diversity of a population.
Stephens argues there is a significant difference between treating the phenomenon of drift as an actual cause or force, and considering other causes, such as selection mutation and migration as forces and causes. Stephens claims that a causal process explanation of drift lets us distinguish it from other forces and this differentiation is crucial. He further argues that drift is both a direction, i.e., it tends to eliminate heterozygosity. It also has a size, which is determined by population size.
Evolution by Lamarckism
Students of biology in high school are often exposed to Jean-Baptiste lamarck's (1744-1829) work. His theory of evolution, also referred to as "Lamarckism which means that simple organisms evolve into more complex organisms by inheriting characteristics that are a product of the use and abuse of an organism. Lamarckism is usually illustrated with an image of a giraffe that extends its neck further to reach the higher branches in the trees. This process would result in giraffes passing on their longer necks to offspring, who then grow even taller.
Lamarck was a French zoologist and, in his inaugural lecture for his course on invertebrate zoology held at the Museum of Natural History in Paris on the 17th of May in 1802, he introduced an innovative concept that completely challenged the previous understanding of organic transformation. In his opinion living things evolved from inanimate matter through a series of gradual steps. Lamarck was not the only one to suggest that this might be the case, but the general consensus is that he was the one being the one who gave the subject his first comprehensive and comprehensive treatment.
The most popular story is that Lamarckism grew into an opponent to Charles Darwin's theory of evolutionary natural selection, and that the two theories battled each other in the 19th century. Darwinism ultimately won which led to what biologists call the Modern Synthesis. 에볼루션 바카라 무료 argues that acquired traits can be passed down through generations and instead argues that organisms evolve through the selective action of environment factors, such as Natural Selection.
While Lamarck believed in the concept of inheritance by acquired characters and his contemporaries also paid lip-service to this notion, it was never an integral part of any of their theories about evolution. This is due in part to the fact that it was never tested scientifically.
It's been over 200 years since the birth of Lamarck and in the field of age genomics, there is a growing body of evidence that supports the heritability acquired characteristics. This is also referred to as "neo Lamarckism", or more commonly epigenetic inheritance. This is a version that is as valid as the popular neodarwinian model.
Evolution by the process of adaptation
One of the most popular misconceptions about evolution is its being driven by a fight for survival. This notion is not true and ignores other forces driving evolution. The struggle for survival is more accurately described as a struggle to survive within a specific environment, which may include not just other organisms, but as well the physical environment.
Understanding adaptation is important to comprehend evolution. The term "adaptation" refers to any characteristic that allows a living organism to survive in its environment and reproduce. It can be a physical structure, like fur or feathers. It could also be a behavior trait such as moving into the shade during hot weather or moving out to avoid the cold at night.
The ability of a living thing to extract energy from its environment and interact with other organisms, as well as their physical environments, is crucial to its survival. The organism needs to have the right genes to create offspring, and it must be able to locate enough food and other resources. The organism should be able to reproduce at a rate that is optimal for its particular niche.
These factors, together with gene flow and mutations can cause an alteration in the ratio of different alleles in the population's gene pool. The change in frequency of alleles could lead to the development of novel traits and eventually new species as time passes.
Many of the characteristics we admire in animals and plants are adaptations. For example lung or gills that extract oxygen from the air, fur and feathers as insulation and long legs to get away from predators and camouflage for hiding. To understand adaptation it is crucial to discern between physiological and behavioral traits.
Physical traits such as large gills and thick fur are physical characteristics. Behavior adaptations aren't an exception, for instance, the tendency of animals to seek companionship or to retreat into the shade in hot weather. Furthermore it is important to note that lack of planning is not a reason to make something an adaptation. Inability to think about the consequences of a decision, even if it appears to be logical, can make it unadaptive.