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What is Free Evolution?

Free evolution is the idea that the natural processes of organisms can lead them to evolve over time. This includes the appearance and development of new species.

This has been demonstrated by many examples of stickleback fish species that can thrive in salt or fresh water, and walking stick insect types that are apprehensive about specific host plants. These mostly reversible trait permutations however, are not able to explain fundamental changes in basic body plans.

Evolution through Natural Selection

Scientists have been fascinated by the development of all the living creatures that live on our planet for centuries. Charles Darwin's natural selectivity is the best-established explanation. This process occurs when individuals who are better-adapted survive and reproduce more than those who are less well-adapted. Over time, the population of individuals who are well-adapted grows and eventually develops into an entirely new species.

Natural selection is an ongoing process and involves the interaction of three factors including reproduction, variation and inheritance. Mutation and sexual reproduction increase genetic diversity in the species. Inheritance is the passing of a person's genetic characteristics to their offspring, which includes both dominant and recessive alleles. Reproduction is the process of producing viable, fertile offspring. This can be accomplished by both asexual or sexual methods.

Natural selection is only possible when all of these factors are in balance. If, for example an allele of a dominant gene causes an organism reproduce and live longer than the recessive allele then the dominant allele is more prevalent in a group. If the allele confers a negative survival advantage or lowers the fertility of the population, it will go away. The process is self-reinforcing, meaning that an organism that has a beneficial trait is more likely to survive and reproduce than one with a maladaptive characteristic. The higher the level of fitness an organism has which is measured by its ability to reproduce and survive, is the more offspring it produces. Individuals with favorable characteristics, like longer necks in giraffes or bright white colors in male peacocks, are more likely to be able to survive and create offspring, so they will make up the majority of the population in the future.

Natural selection is only an element in the population and not on individuals. This is a major distinction from the Lamarckian theory of evolution, which states that animals acquire traits through use or lack of use. For example, if a animal's neck is lengthened by reaching out to catch prey its offspring will inherit a more long neck. The difference in neck length between generations will persist until the giraffe's neck gets so long that it can not breed with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles from one gene are distributed randomly in a population. Eventually, one of them will reach fixation (become so common that it can no longer be removed by natural selection) and the other alleles drop to lower frequencies. In the extreme, this leads to one allele dominance. The other alleles are essentially eliminated, and heterozygosity falls to zero. In a small group it could result in the complete elimination of recessive gene. This is known as a bottleneck effect and it is typical of evolutionary process that takes place when a large number of individuals move to form a new group.

A phenotypic bottleneck could happen when the survivors of a disaster like an epidemic or mass hunting event, are concentrated into a small area. The surviving individuals will be mostly homozygous for the dominant allele which means that they will all have the same phenotype, and consequently have the same fitness characteristics. This situation could be caused by earthquakes, war, or 에볼루션 코리아 even plagues. Whatever the reason the genetically distinct group that remains is prone to genetic drift.

Walsh Lewens, Walsh and Ariew define drift as a deviation from the expected values due to differences in fitness. They provide the famous case of twins that are genetically identical and 에볼루션 코리아 have exactly the same phenotype. However one is struck by lightning and dies, but the other is able to reproduce.

This type of drift is vital to the evolution of an entire species. However, it's not the only method to progress. Natural selection is the most common alternative, 에볼루션 코리아 where mutations and migrations maintain phenotypic diversity within the population.

Stephens argues there is a vast distinction between treating drift as an agent or cause and considering other causes, such as migration and selection mutation as forces and causes. He argues that a causal-process explanation of drift lets us differentiate it from other forces, and this differentiation is crucial. He argues further that drift is both an orientation, i.e., it tends towards eliminating heterozygosity. It also has a size that is determined by the size of the population.

Evolution by Lamarckism

Biology students in high school are frequently exposed to Jean-Baptiste lamarck's (1744-1829) work. His theory of evolution is generally referred to as "Lamarckism" and it states that simple organisms grow into more complex organisms through the inheritance of characteristics that result from an organism's natural activities usage, use and disuse. Lamarckism can be demonstrated by an giraffe's neck stretching to reach higher levels of leaves in the trees. This would result in giraffes passing on their longer necks to offspring, which then get 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 the conventional wisdom about organic transformation. According to Lamarck, living things evolved from inanimate matter through a series gradual steps. Lamarck wasn't the only one to suggest this, but he was widely regarded as the first to give the subject a comprehensive and general explanation.

The popular narrative is that Lamarckism was an opponent to Charles Darwin's theory of evolution by natural selection and that the two theories fought each other in the 19th century. Darwinism ultimately won which led to what biologists call the Modern Synthesis. The theory denies that acquired characteristics are passed down from generation to generation and instead argues that organisms evolve through the influence of environment factors, such as Natural Selection.

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

It has been more than 200 year since Lamarck's birth, and in the age genomics, there is a growing evidence base that supports the heritability of acquired traits. This is referred to as "neo Lamarckism", or more commonly epigenetic inheritance. It is a version of evolution that is as valid as the more well-known Neo-Darwinian theory.

Evolution through the process of adaptation

One of the most popular misconceptions about evolution is that it is driven by a type of struggle for survival. This notion is not true and ignores other forces driving evolution. The struggle for existence is better described as a fight to survive in a specific environment. This could include not just other organisms but also the physical environment itself.

To understand how evolution functions, it is helpful to understand what is adaptation. It refers to a specific feature that allows an organism to live and 에볼루션 바카라 무료 reproduce within its environment. It can be a physical structure, like fur or feathers. Or it can be a trait of behavior, like moving into the shade during the heat, or 에볼루션 게이밍 moving out to avoid the cold at night.

The survival of an organism depends on its ability to draw energy from the environment and interact with other living organisms and their physical surroundings. The organism must have the right genes for producing offspring and to be able to access sufficient food and resources. In addition, the organism should be capable of reproducing itself in a way that is optimally within its environmental niche.

These factors, along with gene flow and mutation, lead to a change in the proportion of alleles (different forms of a gene) in the gene pool of a population. As time passes, 에볼루션 코리아 this shift in allele frequencies could result in the emergence of new traits and eventually new species.

A lot of the traits we admire in animals and plants are adaptations, such as the lungs or gills that extract oxygen from the air, feathers or fur for insulation and long legs for running away from predators and camouflage to hide. To comprehend adaptation, it is important to discern between physiological and behavioral traits.

Physiological adaptations like the thick fur or gills are physical traits, while behavioral adaptations, such as the desire to find companions or to move to the shade during hot weather, are not. Additionally it is important to understand that a lack of forethought is not a reason to make something an adaptation. In fact, failing to think about the consequences of a choice can render it unadaptive, despite the fact that it may appear to be reasonable or even essential.