What is Free Evolution?

Free evolution is the concept that natural processes can cause organisms to evolve over time. This includes the evolution of new species and change in appearance of existing species.

Numerous examples have been offered of this, such as different kinds of stickleback fish that can live in fresh or salt water and walking stick insect varieties that are attracted to particular host plants. These mostly reversible traits permutations do not explain the fundamental changes in the body's basic plans.



Evolution by Natural Selection

The development of the myriad living creatures on Earth is a mystery that has fascinated scientists for centuries. Charles Darwin's natural selection is the most well-known explanation. This process occurs when individuals who are better-adapted have more success in reproduction and survival than those who are less well-adapted. As time passes, a group of well-adapted individuals increases and eventually becomes a new species.

Natural selection is an ongoing process and involves the interaction of 3 factors including reproduction, variation and inheritance. Variation is caused by mutation and sexual reproduction, both of which increase the genetic diversity within a species. Inheritance is the transfer of a person's genetic characteristics to the offspring of that person which includes both recessive and dominant alleles. Reproduction is the production of fertile, viable offspring which includes both asexual and sexual methods.

All of these factors have to be in equilibrium for natural selection to occur. For example when an allele that is dominant at the gene causes an organism to survive and reproduce more often than the recessive allele, the dominant allele will be more prominent within the population. If the allele confers a negative advantage to survival or decreases the fertility of the population, it will be eliminated. This process is self-reinforcing meaning that an organism that has an adaptive trait will survive and reproduce more quickly than those with a maladaptive feature. The higher the level of fitness an organism has, measured by its ability reproduce and endure, is the higher number of offspring it will produce. People with good characteristics, like longer necks in giraffes, or bright white color patterns in male peacocks are more likely to be able to survive and create offspring, which means they will become the majority of the population over time.

Natural selection is only a force for populations, not individual organisms. This is a significant distinction from the Lamarckian theory of evolution which argues that animals acquire characteristics through use or neglect. For instance, if the animal's neck is lengthened by stretching to reach prey its offspring will inherit a larger neck. The difference in neck length between generations will continue until the giraffe's neck gets too long that it can no longer breed with other giraffes.

Evolution through Genetic Drift

In genetic drift, alleles at a gene may be at different frequencies within a population by chance events. Eventually, one of them will reach fixation (become so widespread that it is unable to be eliminated through natural selection), while other alleles will fall to lower frequency. This can lead to an allele that is dominant at the extreme. https://lancaster-levesque.blogbright.net/the-unknown-benefits-of-evolution-free-baccarat-1734946599 have been basically eliminated and heterozygosity has diminished to a minimum. In a small number of people, this could lead to the complete elimination of the recessive allele. This is known as the bottleneck effect and is typical of an evolutionary process that occurs whenever a large number individuals migrate to form a population.

A phenotypic bottleneck can also occur when the survivors of a catastrophe like an outbreak or a mass hunting incident are concentrated in a small area. The survivors will share a dominant allele and thus will share the same phenotype. This situation could be caused by earthquakes, war or even plagues. Whatever the reason, the genetically distinct population that is left might be prone to genetic drift.

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

This kind of drift could play a very important part in the evolution of an organism. However, it is not the only way to evolve. The primary alternative is to use a process known as natural selection, in which the phenotypic diversity of an individual is maintained through mutation and migration.

Stephens argues there is a huge distinction between treating drift as an agent or cause and considering other causes, such as migration and selection as forces and causes. He claims that a causal process explanation of drift permits us to differentiate it from other forces, and this distinction is vital. He further argues that drift has a direction, that is it tends to eliminate heterozygosity. It also has a size, which is determined by the size of population.

Evolution through Lamarckism

When high school students study biology, they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution is generally called "Lamarckism" and it states that simple organisms grow into more complex organisms by the inheritance of traits that are a result of the natural activities of an organism use and misuse. Lamarckism is usually illustrated with the image of a giraffe extending its neck further to reach leaves higher up in the trees. This process would cause giraffes to pass on their longer necks to offspring, who would then get taller.

Lamarck Lamarck, a French zoologist, presented an idea that was revolutionary in his opening lecture at the Museum of Natural History of Paris. He challenged the conventional wisdom on organic transformation. According Lamarck, living organisms evolved from inanimate matter through a series gradual steps. Lamarck was not the first to propose this but he was regarded as the first to offer the subject a comprehensive and general explanation.

The most popular story is that Charles Darwin's theory on natural selection and Lamarckism fought in the 19th Century. Darwinism eventually prevailed and led to what biologists call the Modern Synthesis. The theory argues the possibility that acquired traits can be inherited, and instead argues that organisms evolve through the selective action of environmental factors, such as natural selection.

Although Lamarck believed in the concept of inheritance through acquired characters and his contemporaries spoke of this idea but it was not an integral part of any of their evolutionary theories. This is partly due to the fact that it was never validated scientifically.

It's been more than 200 year since Lamarck's birth, and in the age genomics, there is an increasing evidence-based body of evidence to support the heritability of acquired traits. This is often referred to as "neo-Lamarckism" or more often epigenetic inheritance. It is a variant of evolution that is just as valid as the more well-known Neo-Darwinian model.

Evolution through adaptation

One of the most commonly-held misconceptions about evolution is its being driven by a struggle for survival. This notion is not true and overlooks other forces that drive evolution. The struggle for existence is better described as a struggle to survive in a particular environment. This could be a challenge for not just other living things but also the physical environment.

Understanding the concept of adaptation is crucial to comprehend evolution. The term "adaptation" refers to any specific characteristic that allows an organism to live and reproduce in its environment. It can be a physical feature, like feathers or fur. Or it can be a trait of behavior, like moving into the shade during hot weather or coming out to avoid the cold at night.

The survival of an organism is dependent on its ability to draw energy from the environment and interact with other organisms and their physical environments. The organism should possess the right genes to produce offspring and to be able to access enough food and resources. The organism should also be able to reproduce at the rate that is suitable for its niche.

These elements, along with mutations and gene flow can cause an alteration in the ratio of different alleles in the population's gene pool. This change in allele frequency can result in the emergence of novel traits and eventually, new species as time passes.

A lot of the traits we find appealing in plants and animals are adaptations. For example, lungs or gills that extract oxygen from air, fur and feathers as insulation, long legs to run away from predators, and camouflage to hide. To understand the concept of adaptation, it is important to differentiate between physiological and behavioral traits.

Physiological adaptations, such as thick fur or gills are physical characteristics, whereas behavioral adaptations, like the tendency to search for friends or to move into the shade in hot weather, aren't. In addition it is important to remember that a lack of thought is not a reason to make something an adaptation. In fact, failure to consider the consequences of a decision can render it ineffective, despite the fact that it may appear to be logical or even necessary.