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What is Free Evolution?

Free evolution is the notion that the natural processes of organisms can lead them to evolve over time. This includes the creation of new species as well as the transformation of the appearance of existing ones.

This is evident in numerous examples such as the stickleback fish species that can thrive in salt or fresh water, and walking stick insect types that prefer specific host plants. These typically reversible traits do not explain the fundamental changes in the basic body plan.

Evolution through Natural Selection

Scientists have been fascinated by the development of all the living organisms that inhabit our planet for ages. The most well-known explanation is Charles Darwin's natural selection process, an evolutionary process that occurs when better-adapted individuals survive and reproduce more effectively than those less well adapted. Over time, a population of well adapted individuals grows and eventually creates a new species.

Natural selection is a process that is cyclical and involves the interaction of 3 factors that are: reproduction, variation and 에볼루션 무료체험 inheritance. Variation is caused by mutation and sexual reproduction, both of which increase the genetic diversity of an animal species. Inheritance refers to the transmission of genetic traits, which include recessive and dominant genes and their offspring. Reproduction is the process of producing viable, fertile offspring. This can be done by both asexual or sexual methods.

All of these factors must be in balance to allow natural selection to take place. If, for example, a dominant gene allele causes an organism reproduce and live longer than the recessive gene allele then the dominant allele becomes more common in a population. If the allele confers a negative advantage to survival or lowers the fertility of the population, it will be eliminated. The process is self-reinforcing, meaning that an organism with a beneficial trait can reproduce and survive longer than one with a maladaptive characteristic. The more fit an organism is, measured by its ability reproduce and survive, is the more offspring it can produce. Individuals with favorable traits, such as a longer neck in giraffes, or 에볼루션 바카라사이트 무료체험 (blogs.cornell.Edu) bright white colors in male peacocks, are more likely to be able to survive and create offspring, which means they will make up the majority of the population over time.

Natural selection only acts on populations, not on individual organisms. This is a significant distinction from the Lamarckian theory of evolution that states that animals acquire traits through usage or inaction. For example, 에볼루션바카라 if a giraffe's neck gets longer through reaching out to catch prey its offspring will inherit a longer neck. The length difference between generations will persist until the giraffe's neck becomes too long that it can not breed with other giraffes.

Evolution by Genetic Drift

In genetic drift, the alleles of a gene could reach different frequencies in a group due to random events. Eventually, one of them will reach fixation (become so widespread that it can no longer be removed through natural selection), while other alleles will fall to lower frequencies. This can lead to a dominant allele in extreme. The other alleles are eliminated, and 에볼루션 사이트 heterozygosity is reduced to zero. In a small population it could lead to the complete elimination of recessive alleles. Such a scenario would be known as a bottleneck effect and it is typical of the kind of evolutionary process that occurs when a lot of individuals migrate to form a new population.

A phenotypic bottleneck could occur when survivors of a catastrophe like an epidemic or mass hunting event, are condensed in a limited area. The survivors will share a dominant allele and thus will have the same phenotype. This situation might be the result of a conflict, earthquake or even a disease. The genetically distinct population, if left, 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 give a famous instance of twins who are genetically identical, share the exact same phenotype and yet one is struck by lightning and dies, while the other lives and reproduces.

This kind of drift could play a crucial role in the evolution of an organism. But, it's not the only way to progress. The main alternative is a process known as natural selection, in which the phenotypic variation of the population is maintained through mutation and migration.

Stephens asserts that there is a huge difference between treating the phenomenon of drift as an agent or cause and treating other causes like migration and selection as forces and causes. He claims that a causal process account of drift allows us to distinguish it from these other forces, and that this distinction is crucial. He argues further that drift has both direction, i.e., 에볼루션 바카라사이트 (linked web site) it tends to reduce heterozygosity. It also has a size that is determined by population size.

Evolution through Lamarckism

Students of biology in high school are often introduced to Jean-Baptiste Lemarck's (1744-1829) work. His theory of evolution, commonly called "Lamarckism is based on the idea that simple organisms evolve into more complex organisms by adopting traits that result from the use and abuse of an organism. Lamarckism is typically illustrated by the image of a giraffe that extends its neck further to reach the higher branches in the trees. This could result in giraffes passing on their longer necks to their offspring, which then become taller.

Lamarck was a French zoologist and, 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 innovative concept that completely challenged previous thinking about organic transformation. According to him living things had evolved from inanimate matter via an escalating series of steps. Lamarck was not the first to propose this however he was widely thought of as the first to offer the subject a thorough and general overview.

The most popular story is that Charles Darwin's theory on evolution by natural selection and Lamarckism were competing in the 19th Century. Darwinism ultimately prevailed which led to what biologists call the Modern Synthesis. The Modern Synthesis theory denies the possibility that acquired traits can be inherited, and instead, it argues that organisms develop through the action of environmental factors, such as natural selection.

Lamarck and his contemporaries supported the notion that acquired characters could be passed down to future generations. However, this idea was never a key element of any of their theories on evolution. This is partly due to the fact that it was never validated scientifically.

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

Evolution by Adaptation

One of the most commonly-held misconceptions about evolution is that it is being driven by a struggle for survival. In fact, this view is a misrepresentation of natural selection and ignores the other forces that determine the rate of evolution. The fight for survival can be more accurately described as a struggle to survive in a certain environment. This may be a challenge for not just other living things but also the physical environment.

To understand how evolution functions, it is helpful to consider what adaptation is. It is a feature that allows a living organism to live in its environment and reproduce. It can be a physiological feature, like feathers or fur, or a behavioral trait 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 environment and to interact with other organisms and their physical environments. The organism must have the right genes to produce offspring, and it should be able to find enough food and other resources. Moreover, the organism must be able to reproduce itself at an optimal rate within its environmental niche.

These factors, together with mutation and gene flow, lead to changes in the ratio of alleles (different types of a gene) in the gene pool of a population. The change in frequency of alleles can result in the emergence of new traits, and eventually new species over time.

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

Physiological adaptations, like thick fur or gills are physical traits, while behavioral adaptations, such as the desire to find friends or to move to shade in hot weather, aren't. Furthermore it is important to note 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 seems to be rational, could make it unadaptive.