What is Free Evolution?

Free evolution is the concept that natural processes can lead to the development of organisms over time. This includes the development of new species and alteration of the appearance of existing ones.

This has been proven by many examples, including stickleback fish varieties that can live in saltwater or fresh water and walking stick insect types that prefer specific host plants. These mostly reversible traits permutations do not explain the fundamental changes in the body's basic plans.

Evolution by Natural Selection

Scientists have been fascinated by the development of all the living organisms that inhabit our planet for centuries. The most well-known explanation is Darwin's natural selection, which occurs when individuals that are better adapted survive and reproduce more effectively than those that are less well-adapted. Over time, a community of well adapted individuals grows and eventually forms a whole new species.

Natural selection is an ongoing process that is characterized by the interaction of three factors including inheritance, variation, and reproduction. Mutation and sexual reproduction increase genetic diversity in an animal species. Inheritance is the term used to describe the transmission of genetic traits, including both dominant and recessive genes to their offspring. Reproduction is the process of producing fertile, viable offspring which includes both sexual and asexual methods.

Natural selection is only possible when all of these factors are in harmony. If, for example, a dominant gene allele allows an organism to reproduce and live longer than the recessive gene, then the dominant allele is more common in a population. However, if the gene confers a disadvantage in survival or reduces fertility, it will be eliminated from the population. The process is self reinforcing meaning that the organism with an adaptive trait will survive and reproduce more quickly than those with a maladaptive trait. The more fit an organism is which is measured by its ability to reproduce and endure, is the higher number of offspring it can produce. People with good traits, such as having a longer neck in giraffes and bright white color patterns in male peacocks are more likely to survive and produce offspring, which means they will eventually make up the majority of the population over time.

Natural selection is only an element in the population and not on individuals. This is a crucial distinction from the Lamarckian evolution theory which holds that animals acquire traits either through usage or inaction. If a giraffe extends its neck to catch prey and the neck grows longer, then its offspring will inherit this characteristic. The difference in neck size between generations will continue to increase until the giraffe becomes unable to breed with other giraffes.

Evolution through Genetic Drift

In genetic drift, alleles within a gene can reach different frequencies in a group by chance events. At some point, one will reach fixation (become so widespread that it cannot be removed by natural selection), while other alleles will fall to lower frequencies. This could lead to an allele that is dominant at the extreme. Other alleles have been basically eliminated and heterozygosity has been reduced to a minimum. In a small group it could result in the complete elimination of recessive gene. This is known as the bottleneck effect and is typical of the evolution process that occurs when a large number individuals migrate to form a group.

A phenotypic bottleneck could occur when the survivors of a catastrophe such as an epidemic or a massive hunting event, are concentrated within a narrow area. The surviving individuals will be mostly homozygous for the dominant allele which means that they will all share the same phenotype, and therefore share the same fitness characteristics. This situation could be caused by war, earthquakes, or even plagues. The genetically distinct population, if it is left vulnerable to genetic drift.

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

에볼루션 무료체험 of drift can play a significant part in the evolution of an organism. It is not the only method for evolution. The primary alternative is a process known as natural selection, in which the phenotypic variation of an individual is maintained through mutation and migration.

Stephens argues that there is a significant difference between treating drift as a force or as an underlying cause, and treating other causes of evolution like mutation, selection, and migration as forces or causes. He claims that a causal-process explanation of drift lets us differentiate it from other forces, and this distinction is crucial. He also claims that drift has a direction: that is it tends to eliminate heterozygosity. He also claims that it also has a size, which is determined by the size of the population.

Evolution through Lamarckism

Students of biology in high school are frequently exposed to Jean-Baptiste lamarck's (1744-1829) work. His theory of evolution is commonly known as "Lamarckism" and it states that simple organisms develop into more complex organisms through the inheritance of traits which result from the organism's natural actions, use and disuse. Lamarckism is illustrated through the giraffe's neck being extended to reach higher branches in the trees. This would cause giraffes to give their longer necks to 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 the 17th of May in 1802, he introduced a groundbreaking concept that radically challenged previous thinking about organic transformation. According Lamarck, living organisms evolved from inanimate material through a series gradual steps. Lamarck was not the first to suggest that this might be the case, but he is widely seen as giving the subject its first broad and comprehensive analysis.

The popular narrative is that Lamarckism grew into an opponent to Charles Darwin's theory of evolution by natural selection and that the two theories battled out in the 19th century. Darwinism eventually won, leading to the development of what biologists today refer to as the Modern Synthesis. The Modern Synthesis theory denies the possibility that acquired traits can be acquired through inheritance and instead, it argues that organisms develop through the action of environmental factors, like natural selection.

While Lamarck endorsed the idea of inheritance through acquired characters and his contemporaries offered a few words about this idea however, it was not a central element in any of their evolutionary theorizing. This is partly because it was never scientifically tested.

It's been more than 200 years since Lamarck was born and in the age genomics, there is a large amount of evidence that supports the heritability of acquired traits. This is often called "neo-Lamarckism" or, more commonly epigenetic inheritance. This is a variant that is 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 struggle to survive. This view is inaccurate and ignores other forces driving evolution. The struggle for existence is better described as a fight to survive in a particular environment. This may include not just other organisms as well as the physical surroundings themselves.

Understanding the concept of adaptation is crucial to understand evolution. The term "adaptation" refers to any characteristic that allows a living thing to live in its environment and reproduce. It can be a physiological feature, such as feathers or fur, or a behavioral trait such as a tendency to move into shade in hot weather or stepping out at night to avoid the cold.

The capacity of an organism to extract energy from its environment and interact with other organisms and their physical environments is essential to its survival. The organism must possess the right genes to produce offspring, and it must be able to access sufficient food and other resources. Moreover, the organism must be capable of reproducing at a high rate within its niche.

These factors, together with gene flow and mutation can result in changes in the ratio of alleles (different varieties of a particular gene) in the population's gene pool. Over time, this change in allele frequencies can result in the emergence of new traits and eventually new species.

A lot of the traits we admire in animals and plants are adaptations, like lung or gills for removing oxygen from the air, fur or feathers to protect themselves, long legs for running away from predators, and camouflage for hiding. However, a complete understanding of adaptation requires paying attention to the distinction between the physiological and behavioral characteristics.

Physiological adaptations like the thick fur or gills are physical traits, whereas behavioral adaptations, like the tendency to search for companions or to retreat into the shade in hot weather, aren't. It is important to remember that a lack of planning does not make an adaptation. In fact, failure to think about the consequences of a behavior can make it ineffective, despite the fact that it appears to be logical or even necessary.