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What is Free Evolution?

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

Many examples have been given of this, such as different varieties of fish called sticklebacks that can live in either salt or fresh water, and walking stick insect varieties that favor specific host plants. These reversible traits can't, however, explain fundamental changes in basic body plans.

Evolution through Natural Selection

The evolution of the myriad living creatures on Earth is a mystery that has fascinated scientists for many centuries. The most widely accepted explanation is that of Charles Darwin's natural selection, a process that is triggered when more well-adapted individuals live longer and reproduce more successfully than those less well-adapted. Over time, a population of well-adapted individuals expands and eventually becomes a new species.

Natural selection is a process that is cyclical and involves the interaction of three factors that are: reproduction, variation and inheritance. Sexual reproduction and 에볼루션 블랙잭 (check out this one from Wikimapia) mutations increase genetic diversity in a species. Inheritance refers the transmission of a person's genetic traits, which include recessive and dominant genes, to their offspring. Reproduction is the process of producing fertile, viable offspring which includes both asexual and sexual methods.

All of these variables must be in harmony for natural selection to occur. If, for example an allele of a dominant gene allows an organism to 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 decreases fertility, it will be eliminated from the population. The process is self-reinforcing, meaning that an organism with a beneficial characteristic is more likely to survive and reproduce than an individual with a maladaptive characteristic. The more offspring an organism can produce the better its fitness which is measured by its ability to reproduce and survive. Individuals with favorable characteristics, like longer necks in giraffes and bright white colors in male peacocks are more likely survive and produce offspring, which means they will eventually make up the majority of the population in the future.

Natural selection only acts on populations, not on individuals. This is a major distinction from the Lamarckian evolution theory, which states that animals acquire traits due to use or lack of use. For instance, if the giraffe's neck gets longer through stretching to reach for prey its offspring will inherit a longer neck. The differences in neck length between generations will continue until the neck of the giraffe becomes so long that it can no longer breed with other giraffes.

Evolution through Genetic Drift

In the process of genetic drift, alleles within a gene can attain different frequencies within a population by chance events. Eventually, only one will be fixed (become common enough that it can no longer be eliminated by natural selection) and the other alleles will diminish in frequency. In the extreme, this leads to dominance of a single allele. The other alleles are eliminated, and heterozygosity is reduced to zero. In a small population, this could lead to the total elimination of recessive alleles. This is called a bottleneck effect, and it is typical of evolutionary process that takes place when a large number of individuals move to form a new population.

A phenotypic bottleneck may occur when the survivors of a disaster such as an epidemic or mass hunting event, are condensed in a limited area. The surviving individuals will be largely homozygous for the dominant allele, which means they will all share the same phenotype, and thus share the same fitness characteristics. This may be the result of a conflict, earthquake or even a disease. The genetically distinct population, if it remains, could be susceptible to genetic drift.

Walsh Lewens, Walsh and Ariew define drift as a deviation from the expected values due to differences in fitness. They provide a well-known instance of twins who are genetically identical, share the exact same phenotype but one is struck by lightening and dies while the other lives and reproduces.

This kind of drift can play a significant role in the evolution of an organism. However, it is not the only way to progress. The most common alternative is to use a process known as natural selection, in which the phenotypic variation of the population is maintained through mutation and 에볼루션게이밍 migration.

Stephens claims that there is a huge difference between treating drift like an actual cause or force, and considering other causes, such as migration and selection as causes and forces. Stephens claims that a causal process account of drift allows us to distinguish it from other forces, and this distinction is vital. He also argues that drift is both direction, i.e., it tends towards eliminating heterozygosity. It also has a size, that is determined by population size.

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, also referred to as "Lamarckism" which means that simple organisms transform into more complex organisms by taking on traits that result from an organism's use and disuse. Lamarckism can be demonstrated by the giraffe's neck being extended to reach higher levels of leaves in the trees. This would cause giraffes to pass on their longer necks to offspring, who then get 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 conventional wisdom about organic transformation. According Lamarck, living organisms evolved from inanimate material by a series of gradual steps. Lamarck was not the only one to suggest that this might be the case, but he is widely seen as being the one who gave the subject its first general and comprehensive analysis.

The popular narrative is that Lamarckism was a rival to Charles Darwin's theory of evolutionary natural selection, and that the two theories fought out in the 19th century. Darwinism eventually prevailed and led to the creation of what biologists today call the Modern Synthesis. The Modern Synthesis theory denies that acquired characteristics can be acquired through inheritance and instead, it argues that organisms develop by the symbiosis of environmental factors, such as natural selection.

While Lamarck endorsed the idea of inheritance through acquired characters and his contemporaries also paid lip-service to this notion, it was never a central element in any of their theories about evolution. This is due to the fact that it was never scientifically tested.

But it is now more than 200 years since Lamarck was born and, in the age of genomics there is a huge body of evidence supporting the possibility of inheritance of acquired traits. This is also referred to as "neo Lamarckism", or more commonly epigenetic inheritance. This is a model that is as valid as the popular Neodarwinian model.

Evolution by Adaptation

One of the most common misconceptions about evolution is being driven by a struggle to survive. In reality, this notion is a misrepresentation of natural selection and ignores the other forces that determine the rate of evolution. The fight for survival can be better described as a fight to survive in a particular environment. This may include not just other organisms as well as the physical environment itself.

Understanding how adaptation works is essential to understand evolution. It refers to a specific feature that allows an organism to survive and reproduce in its environment. It can be a physiological feature, such as feathers or fur or a behavioral characteristic like moving to the shade during hot weather or coming out at night to avoid the cold.

An organism's survival depends on its ability to draw energy from the surrounding environment and interact with other living organisms and their physical surroundings. The organism should possess the right genes to create offspring and to be able to access sufficient food and resources. Moreover, the organism must be capable of reproducing at an optimal rate within its niche.

These elements, along with mutations and gene flow can result in changes in the proportion of different alleles within the gene pool of a population. This shift in the 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 the lungs or gills which draw oxygen from air feathers and fur for insulation and long legs to get away from predators and camouflage to conceal. To comprehend adaptation, it is important to differentiate between physiological and 에볼루션 게이밍 에볼루션 무료 바카라 바카라 (Cannon-nymand-3.thoughtlanes.net) behavioral traits.

Physiological adaptations like the thick fur or 에볼루션게이밍 gills are physical traits, while behavioral adaptations, such as the desire to find companions or to move to the shade during hot weather, 에볼루션 aren't. In addition, it is important to remember that a lack of thought does not mean that something is an adaptation. Inability to think about the effects of a behavior even if it appears to be rational, could cause it to be unadaptive.