What is Free Evolution?

Free evolution is the concept that the natural processes that organisms go through can cause them to develop over time. This includes the evolution of new species as well as the alteration of the appearance of existing species.

This has been demonstrated by many examples, including stickleback fish varieties that can live in saltwater or fresh water and 에볼루션 바카라 사이트 walking stick insect species that prefer particular host plants. These are mostly reversible traits however, are not able to explain fundamental changes in basic body plans.

Evolution by Natural Selection

Scientists have been fascinated by the development of all living creatures that live on our planet for ages. Charles Darwin's natural selection is the most well-known explanation. This happens when people who are more well-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 3 factors that are: reproduction, variation and inheritance. Variation is caused by mutations and sexual reproduction, both of which increase the genetic diversity of a species. Inheritance is the transfer of a person's genetic characteristics to his or her offspring, which includes both recessive and dominant alleles. Reproduction is the process of producing viable, fertile offspring. This can be accomplished via sexual or asexual methods.

Natural selection is only possible when all the factors are in balance. If, for instance an allele of a dominant gene causes an organism reproduce and survive more than the recessive gene allele then the dominant allele will become more common in a population. However, if the gene confers an unfavorable survival advantage or reduces fertility, it will disappear from the population. The process is self-reinforced, meaning that a species that has a beneficial trait is more likely to survive and reproduce than an individual with an unadaptive trait. The greater an organism's fitness, measured by its ability reproduce and endure, is the higher number of offspring it can produce. Individuals with favorable traits, like having a longer neck in giraffes or bright white patterns of color in male peacocks are more likely be able to survive and create offspring, so they will eventually make up the majority of the population in the future.

Natural selection is a factor in populations and not on individuals. This is a significant distinction from the Lamarckian theory of evolution which states that animals acquire traits by use or inactivity. If a giraffe expands its neck to catch prey and the neck grows larger, then its children will inherit this characteristic. 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

In genetic drift, alleles of a gene could be at different frequencies in a group by chance events. Eventually, one of them will attain fixation (become so common that it cannot be eliminated through natural selection), while other alleles will fall to lower frequency. In the extreme it can lead to one allele dominance. The other alleles are eliminated, and heterozygosity is reduced to zero. In a small population this could lead to the complete elimination of the recessive gene. This scenario is called the bottleneck effect. It is typical of the evolution process that occurs when the number of individuals migrate to form a group.

A phenotypic bottleneck could occur when the survivors of a catastrophe, such as an epidemic or a massive hunt, are confined in a limited area. The survivors will have a dominant allele and thus will have the same phenotype. This situation might be the result of a conflict, earthquake, or even a plague. Whatever the reason the genetically distinct group that is left might 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 the famous example of twins who are genetically identical and share the same phenotype. However one is struck by lightning and dies, while the other continues to reproduce.

This kind of drift could play a very important role in the evolution of an organism. However, it is not the only way to progress. Natural selection is the most common alternative, where mutations and migration maintain the phenotypic diversity in a population.

Stephens claims that there is a significant difference between treating drift as a force or a cause and considering other causes of evolution such as mutation, selection, and migration as forces or causes. He argues that a causal-process account of drift allows us separate it from other forces, and this distinction is crucial. He argues further that drift has both direction, i.e., it tends to eliminate heterozygosity. It also has a size that is determined by population size.

Evolution by Lamarckism

Biology students in high school are frequently exposed to Jean-Baptiste lamarck's (1744-1829) work. His theory of evolution, often referred to as "Lamarckism" which means that simple organisms evolve into more complex organisms through inheriting characteristics that are a product of an organism's use and disuse. Lamarckism can be demonstrated by the giraffe's neck being extended to reach higher branches in the trees. This would cause the longer necks of giraffes to be passed to their offspring, who would grow 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 innovative concept that completely challenged the previous understanding of organic transformation. According to him living things had evolved from inanimate matter through an escalating series of steps. Lamarck was not the first to suggest that this might be the case but his reputation is widely regarded as being the one who gave the subject its first general and 에볼루션 사이트 comprehensive analysis.

The most popular story is that Charles Darwin's theory on natural selection and Lamarckism fought in the 19th century. Darwinism ultimately prevailed and led to what biologists refer to as the Modern Synthesis. The theory argues that acquired traits can be passed down through generations and instead argues organisms evolve by the selective action of environment factors, including Natural Selection.

Lamarck and his contemporaries supported the idea that acquired characters could be passed down to future generations. However, this idea was never a central part of any of their theories about evolution. This is due to the fact that it was never tested scientifically.

However, it has been more than 200 years since Lamarck was born and in the age genomics there is a huge body of evidence supporting the heritability of acquired traits. This is sometimes called "neo-Lamarckism" or more often 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 fight for survival. In fact, this view is a misrepresentation of natural selection and ignores the other forces that are driving evolution. The struggle for survival is more precisely described as a fight to survive within a specific environment, 에볼루션 사이트 which may involve not only other organisms, but also the physical environment itself.

Understanding how adaptation works is essential to understand evolution. Adaptation is any feature that allows a living thing to live in its environment and 에볼루션 룰렛 reproduce. It could be a physical feature, like fur or feathers. Or it can be a characteristic of behavior, like moving towards shade during the heat, or moving out to avoid the cold at night.

The survival of an organism depends on its ability to obtain energy from the environment and to interact with other living organisms and their physical surroundings. The organism must possess the right genes to produce offspring, and must be able to find sufficient food and other resources. The organism must also be able to reproduce at an amount that is appropriate for its niche.

These elements, in conjunction with gene flow and mutation can result in a change in the proportion of alleles (different types of a gene) in the population's gene pool. As time passes, this shift in allele frequency can result in the development of new traits, and eventually new species.

A lot of the traits we admire about animals and plants are adaptations, for example, lung or gills for removing oxygen from the air, feathers or fur to protect themselves and long legs for running away from predators and camouflage for hiding. To comprehend adaptation, it is important to distinguish between behavioral and physiological characteristics.

Physiological adaptations, such as the thick fur or gills are physical characteristics, whereas behavioral adaptations, such as the desire to find companions or to retreat to the shade during hot weather, aren't. In addition, it is important to understand that a lack of forethought is not a reason to make something an adaptation. Inability to think about the consequences of a decision even if it seems to be rational, could make it inflexible.