Why Free Evolution Is Relevant 2024

What is Free Evolution?

Free evolution is the notion that natural processes can cause organisms to develop over time. This includes the creation of new species and the alteration of the appearance of existing species.

This has been demonstrated by many examples, including stickleback fish varieties that can be found in salt or fresh water, and walking stick insect types that are apprehensive about particular host plants. These mostly reversible trait permutations can't, however, explain fundamental changes in basic body plans.

Evolution by Natural Selection

The evolution of the myriad living organisms on Earth is a mystery that has intrigued scientists for decades. The most well-known explanation is that of Charles Darwin's natural selection process, which is triggered when more well-adapted individuals live longer and reproduce more effectively 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 a process that is cyclical and involves the interaction of three factors that are: reproduction, variation and inheritance. Variation is caused by mutations and sexual reproduction both of which increase the genetic diversity within the species. Inheritance refers to the passing of a person's genetic traits to their offspring which includes both recessive and dominant alleles. Reproduction is the production of fertile, viable offspring, which includes both sexual and asexual methods.

Natural selection only occurs when all of these factors are in balance. For example when the dominant allele of a gene causes an organism to survive and reproduce more often than the recessive allele, the dominant allele will become more prevalent within the population. If the allele confers a negative survival advantage or reduces the fertility of the population, it will be eliminated. The process is self-reinforced, meaning that an organism with a beneficial trait is more likely to survive and reproduce than one with a maladaptive characteristic. The more offspring that an organism has, the greater its fitness, which is measured by its capacity to reproduce itself and live. Individuals with favorable traits, like the long neck of Giraffes, or the bright white patterns on male peacocks, are more likely than others to survive and reproduce, which will eventually lead to them becoming the majority.

Natural selection is only a factor in populations and not on individuals. This is a crucial distinction from the Lamarckian theory of evolution that states that animals acquire traits due to use or lack of use. If a giraffe expands its neck to reach prey and its neck gets larger, then its offspring will inherit this characteristic. The difference in neck length between generations will continue until the neck of the giraffe becomes so long that it can no longer breed with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles from a gene are randomly distributed in a population. In the end, one 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 an allele that is dominant in extreme. Other alleles have been basically eliminated and heterozygosity has diminished to zero. In a small population, this could result in the complete elimination the recessive gene. This is known as the bottleneck effect. It is typical of an evolutionary process that occurs when the number of individuals migrate to form a population.

A phenotypic  bottleneck may 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 carry an dominant allele, and will share the same phenotype. This can be caused by war, earthquakes or even a plague. Whatever the reason the genetically distinct population that remains could be prone to genetic drift.

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

This kind of drift can play a significant role in the evolution of an organism. But, it's not the only way to evolve. Natural selection is the most common alternative, in which mutations and migration keep the phenotypic diversity in a population.

Stephens claims that there is a big difference between treating drift as a force or a cause and treating other causes of evolution like mutation, selection, and migration as forces or causes. He argues that a causal process explanation of drift permits us to differentiate it from other forces, and that this distinction is crucial. He further argues that drift has an orientation, i.e., it tends to eliminate heterozygosity.  무료 에볼루션  has a size, which is determined by population size.

Evolution through Lamarckism

Biology students in high school are often introduced to Jean-Baptiste Lemarck's (1744-1829) work. His theory of evolution is often called "Lamarckism" and it states that simple organisms develop into more complex organisms through the inheritance of traits which result from the natural activities of an organism use and misuse. Lamarckism is illustrated through an giraffe's neck stretching to reach higher branches in the trees. This causes the necks of giraffes that are longer to be passed onto their offspring who would then become taller.

Lamarck was a French Zoologist. In his inaugural lecture for his course on invertebrate Zoology at the Museum of Natural History in Paris on 17 May 1802, he introduced an original idea that fundamentally challenged the conventional wisdom about organic transformation. In his opinion, living things had evolved from inanimate matter through the gradual progression of events. Lamarck was not the first to make this claim however he was widely considered to be the first to offer the subject a comprehensive and general overview.

The most popular story is that Charles Darwin's theory of evolution by natural selection and Lamarckism were competing during the 19th century. Darwinism ultimately won, leading to what biologists call the Modern Synthesis. This theory denies acquired characteristics can be passed down and instead argues that organisms evolve through the selective action of environment factors, such as Natural Selection.

Lamarck and his contemporaries believed in the notion that acquired characters could be passed down to future generations. However, this concept was never a key element of any of their evolutionary theories. This is partly because it was never scientifically validated.

It has been more than 200 year since Lamarck's birth, and in the age genomics, there is an increasing evidence base that supports the heritability-acquired characteristics. This is referred to as "neo Lamarckism", or more generally epigenetic inheritance. This is a model that is just as valid as the popular neodarwinian model.

Evolution by Adaptation

One of the most popular misconceptions about evolution is that it is being driven by a fight for survival. 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 in a specific environment, which may be a struggle that involves not only other organisms, but also the physical environment.

To understand how evolution works, it is helpful to understand what is adaptation. It is a feature that allows living organisms to survive in its environment and reproduce. It can be a physiological structure like feathers or fur, or a behavioral trait, such as moving into the shade in the heat or leaving at night to avoid the cold.

The capacity of an organism to draw energy from its environment and interact with other organisms, as well as their physical environment is essential to its survival. The organism must possess the right genes to produce offspring and be able find enough food and resources. Moreover, the organism must be capable of reproducing itself at an optimal rate within its environmental niche.

These factors, along with gene flow and mutation result in a change in the proportion of alleles (different forms of a gene) in a population's gene pool. This shift in the frequency of alleles can result in the emergence of new traits, and eventually, new species in the course of time.

Many of the characteristics we find appealing in animals and plants are adaptations. For instance lung or gills that extract oxygen from the air feathers and fur as insulation, long legs to run away from predators and camouflage to conceal. To understand adaptation it is crucial to differentiate between physiological and behavioral characteristics.

Physical traits such as the thick fur and gills are physical traits. Behavior adaptations aren't an exception, for instance, the tendency of animals to seek companionship or to retreat into the shade during hot temperatures. It is also important to remember that a the absence of planning doesn't make an adaptation. In fact, failing to think about the implications of a decision can render it unadaptive, despite the fact that it may appear to be logical or even necessary.