What is Free Evolution?

Free evolution is the notion that natural processes can cause organisms to develop over time. This includes the emergence and development of new species.

Numerous examples have been offered of this, including various varieties of stickleback fish that can live in fresh or salt water and walking stick insect varieties that are attracted to specific host plants. These typically reversible traits do not explain the fundamental changes in the basic body plan.

Evolution through Natural Selection

The development of the myriad living creatures on Earth is an enigma that has intrigued scientists for centuries. Charles Darwin's natural selection is the most well-known explanation. This happens when individuals who are better-adapted survive and reproduce more than those who are less well-adapted. Over time, a population of well adapted individuals grows and eventually becomes a new species.

에볼루션 사이트 is an ongoing process that involves the interaction of three elements: variation, inheritance and reproduction. Sexual reproduction and mutations increase the genetic diversity of the species. Inheritance refers to the transmission of a person's genetic traits, which include recessive and dominant genes to their offspring. Reproduction is the generation of viable, fertile offspring, which includes both sexual and asexual methods.

All of these factors must be in balance to allow natural selection to take place. For example the case where the dominant allele of a gene can cause an organism to live and reproduce more often than the recessive allele the dominant allele will become more prevalent in the population. But if the allele confers an unfavorable survival advantage or decreases fertility, it will be eliminated from the population. The process is self reinforcing which means that an organism that has an adaptive trait will live and reproduce far more effectively than those with a maladaptive feature. The greater an organism's fitness which is measured by its ability to reproduce and survive, is the greater number of offspring it will produce. Individuals with favorable traits, such as having a longer neck in giraffes or bright white color patterns in male peacocks are more likely to survive and have offspring, and thus will make up the majority of the population over time.

Natural selection is only a force for populations, not on individuals. This is a crucial distinction from the Lamarckian theory of evolution that states that animals acquire traits either through usage or inaction. If a giraffe expands its neck to catch prey and the neck grows larger, then its offspring will inherit this characteristic. The difference in neck length between generations will persist until the neck of the giraffe becomes so long that it can not breed with other giraffes.

Evolution through Genetic Drift

In genetic drift, the alleles at a gene may attain different frequencies in a group by chance events. In the end, only one will be fixed (become common enough that it can no longer be eliminated by natural selection), and the other alleles drop in frequency. This could lead to a dominant allele at the extreme. The other alleles are eliminated, and heterozygosity decreases to zero. In a small number of people, this could lead to the complete elimination of the recessive allele. This is known as a bottleneck effect and it is typical of evolutionary process that occurs when a large number of individuals move to form a new population.

A phenotypic 'bottleneck' can also occur when survivors of a disaster such as an outbreak or mass hunting event are confined to an area of a limited size. The survivors will be mostly homozygous for the dominant allele meaning that they all share the same phenotype and will thus share the same fitness characteristics. This situation might be caused by a conflict, earthquake or even a cholera outbreak. The genetically distinct population, if left vulnerable to genetic drift.

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

This type of drift is vital to the evolution of a species. It's not the only method of evolution. Natural selection is the primary alternative, in which mutations and migrations maintain the phenotypic diversity of a population.


Stephens claims that there is a huge difference between treating drift like an actual cause or force, and treating other causes such as migration and selection mutation as causes and forces. He argues that a causal-process explanation of drift lets us differentiate it from other forces, and this differentiation is crucial. He further argues that drift is a directional force: that is it tends to reduce heterozygosity, and that it also has a magnitude, which is determined by the size of the 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 commonly known as "Lamarckism" and it asserts that simple organisms evolve into more complex organisms via the inheritance of traits that are a result of the natural activities of an organism usage, use and disuse. Lamarckism is illustrated through the giraffe's neck being extended to reach higher leaves in the trees. 에볼루션 슬롯 could cause the necks of giraffes that are longer to be passed to their offspring, who would then become 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 17 May 1802, he presented an innovative concept that completely challenged previous thinking about organic transformation. According Lamarck, living organisms evolved from inanimate material through a series of gradual steps. Lamarck wasn't the only one to suggest this but he was regarded as the first to offer the subject a comprehensive and general explanation.

The predominant story is that Charles Darwin's theory on natural selection and Lamarckism fought in the 19th Century. Darwinism eventually prevailed, leading to the development of what biologists refer to as the Modern Synthesis. This theory denies that traits acquired through evolution can be inherited, and instead argues that organisms evolve through the action of environmental factors, including natural selection.

While Lamarck believed in the concept of inheritance through acquired characters and his contemporaries spoke of this idea but it was not a major feature in any of their evolutionary theories. This is partly because it was never scientifically validated.

It's been over 200 years since the birth of Lamarck and in the field of age genomics there is a growing evidence base that supports the heritability of acquired traits. This is also referred to as "neo Lamarckism", or more generally epigenetic inheritance. It is a version of evolution that is as relevant as the more popular Neo-Darwinian theory.

Evolution by the process of adaptation

One of the most widespread misconceptions about evolution is that it is a result of a kind of struggle for survival. This view is inaccurate and ignores other forces driving evolution. The fight for survival is better described as a struggle to survive in a specific environment. This can be a challenge for not just other living things as well as the physical surroundings themselves.

To understand how evolution functions, it is helpful to consider what adaptation is. It is a feature that allows a living thing to survive in its environment and reproduce. It could be a physiological structure, like feathers or fur or a behavior, such as moving to the shade during the heat or leaving at night to avoid the cold.

The ability of an organism to draw energy from its surroundings and interact with other organisms as well as their physical environment, is crucial to its survival. 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 be able to reproduce itself at the rate that is suitable for its niche.

These elements, in conjunction with gene flow and mutation result in an alteration in the percentage of alleles (different forms of a gene) in the gene pool of a population. This change in allele frequency can lead to the emergence of new traits, and eventually, new species in the course of time.

A lot of the traits we admire in plants and animals are adaptations. For example the lungs or gills which draw oxygen from air feathers and fur for insulation, long legs to run away from predators and camouflage to conceal. However, a thorough understanding of adaptation requires a keen eye to the distinction between physiological and behavioral characteristics.

Physiological traits like the thick fur and gills are physical traits. Behavioral adaptations are not an exception, for instance, the tendency of animals to seek companionship or retreat into shade during hot weather. Furthermore, it is important to understand that a lack of forethought does not make something an adaptation. In fact, failure to think about the consequences of a behavior can make it unadaptive even though it might appear logical or even necessary.