What is Free Evolution?
Free evolution is the concept that natural processes can cause organisms to develop over time. This includes the emergence and development of new species.
This has been proven by many examples such as the stickleback fish species that can thrive in fresh or saltwater and walking stick insect species that prefer particular host plants. These mostly reversible traits permutations are not able to explain fundamental changes to basic body plans.
Evolution through Natural Selection
The development of the myriad living organisms on Earth is a mystery that has intrigued scientists for centuries. The most widely accepted explanation is that of Charles Darwin's natural selection process, an evolutionary process that occurs when better-adapted individuals survive and reproduce more successfully than those less well adapted. As time passes, the number of well-adapted individuals becomes larger and eventually creates an entirely new species.
Natural selection is an ongoing process and involves the interaction of 3 factors: variation, reproduction and inheritance. Variation is caused by mutation and sexual reproduction both of which enhance the genetic diversity of the species. Inheritance refers to the transmission of a person's genetic traits, including both dominant and recessive genes to their offspring. Reproduction is the process of generating viable, fertile offspring. This can be done through sexual or asexual methods.
All of these elements have to be in equilibrium for natural selection to occur. For example when a dominant allele at a gene causes an organism to survive and reproduce more often than the recessive allele, the dominant allele will be more common within the 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, which means that an organism with a beneficial trait can reproduce and survive longer than an individual with an inadaptive trait. The more offspring an organism can produce the more fit it is, which is measured by its capacity to reproduce itself and survive. Individuals with favorable traits, such as longer necks in giraffes or bright white colors in male peacocks are more likely to survive and have offspring, which means they will make up the majority of the population over time.
Natural selection is an element in the population and not on individuals. This is a crucial distinction from the Lamarckian theory of evolution that states that animals acquire traits due to the use or absence of use. For instance, if the giraffe's neck gets longer through stretching to reach for prey and its offspring will inherit a more long neck. The differences in neck size between generations will continue to increase until the giraffe is unable to breed with other giraffes.
Evolution by Genetic Drift
In the process of genetic drift, alleles of a gene could attain different frequencies within a population through random events. At some point, only one of them will be fixed (become common enough that it can no longer be eliminated through natural selection), and the rest of the alleles will diminish in frequency. In extreme cases it can lead to a single allele dominance. The other alleles have been virtually eliminated and heterozygosity diminished to zero. In a small population this could result in the total elimination of recessive allele. Such a scenario would be called a bottleneck effect, and it is typical of the kind of evolutionary process when a large number of individuals move to form a new population.
A phenotypic bottleneck could occur when the survivors of a catastrophe, such as an epidemic or a mass hunting event, are condensed in a limited area. The surviving individuals will be largely homozygous for the dominant allele, meaning that they all share the same phenotype, and consequently have the same fitness traits. This can be caused by earthquakes, war, 에볼루션 슬롯게임 (Evolutionkr.Kr) or even plagues. The genetically distinct population, if it is left, could be susceptible to genetic drift.
Walsh, Lewens, and Ariew employ Lewens, Walsh and Ariew employ a "purely outcome-oriented" definition of drift as any deviation from expected values for different fitness levels. They cite the famous example of twins who are genetically identical and share the same phenotype. However, one is struck by lightning and dies, whereas the other is able to reproduce.
This type of drift can play a significant part in the evolution of an organism. However, it's not the only method to progress. Natural selection is the primary alternative, where mutations and migration maintain the phenotypic diversity of the population.
Stephens asserts that there is a significant difference between treating drift as a force or as an underlying cause, and treating other causes of evolution such as selection, mutation, and migration as forces or causes. He claims that a causal-process account of drift allows us distinguish it from other forces and that this distinction is essential. He also argues that drift is a directional force: that is it tends to reduce heterozygosity. He also claims that it also has a size, which is determined by population size.
Evolution by Lamarckism
In high school, students study biology, they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, also called "Lamarckism which means that simple organisms develop into more complex organisms through adopting traits that result from the use and abuse of an organism. Lamarckism is usually illustrated with a picture of a giraffe stretching its neck to reach leaves higher up in the trees. This process would cause giraffes to pass on their longer necks to their offspring, who then get taller.
Lamarck the French zoologist, presented a revolutionary concept in his opening lecture at the Museum of Natural History of Paris. He challenged the conventional wisdom on organic transformation. In his opinion living things evolved from inanimate matter through an escalating series of steps. Lamarck was not the first 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 its first broad and comprehensive treatment.
The dominant story is that Charles Darwin's theory on evolution by natural selection and Lamarckism fought during the 19th century. Darwinism eventually won and led to the development of what biologists today call the Modern Synthesis. This theory denies the possibility that acquired traits can be inherited, and instead, it argues that organisms develop by the symbiosis of environmental factors, such as natural selection.
Lamarck and his contemporaries supported the notion that acquired characters could be passed on to the next generation. However, this concept was never a key element of any of their evolutionary theories. This is largely due to the fact that it was never validated scientifically.
But it is now more than 200 years since Lamarck was born and in the age genomics there is a vast amount of evidence that supports the heritability of acquired traits. This is also known as "neo Lamarckism", or more generally epigenetic inheritance. This is a model that is just as valid as the popular neodarwinian model.
Evolution through Adaptation
One of the most popular misconceptions about evolution is that it is a result of a kind of struggle for survival. This notion is not true and overlooks other forces that drive evolution. The struggle for survival is more effectively described as a struggle to survive within a particular environment, which could include not just other organisms but as well the physical environment.
To understand how evolution operates it is beneficial to think about what adaptation is. It refers to a specific characteristic that allows an organism to live and reproduce within its environment. It could be a physiological feature, such as fur or feathers or a behavioral characteristic like moving to the shade during the heat or leaving at night to avoid the cold.
An organism's survival depends on its ability to obtain energy from the surrounding environment and interact with other living organisms and their physical surroundings. The organism needs to have the right genes to generate offspring, and it should be able to find sufficient food and other resources. The organism must also be able to reproduce at the rate that is suitable for its niche.
These factors, in conjunction with mutations and gene flow, can lead to changes in the proportion of different alleles in the population's gene pool. The change in frequency of alleles can lead to the emergence of new traits and eventually, new species as time passes.
A lot of the traits we admire about animals and plants are adaptations, such as lungs or gills to extract oxygen from the air, feathers or fur to provide insulation, long legs for running away from predators, and camouflage for hiding. However, a thorough understanding of adaptation requires attention to the distinction between behavioral and physiological characteristics.
Physiological traits like the thick fur and gills are physical traits. The behavioral adaptations aren't like the tendency of animals to seek out companionship or move into the shade during hot temperatures. In addition, it is important to note that a lack of thought does not mean that something is an adaptation. A failure to consider the consequences of a decision, even if it appears to be rational, could make it inflexible.