What is Free Evolution?

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

This has been demonstrated by many examples such as the stickleback fish species that can be found in salt or fresh water, and walking stick insect species that are apprehensive about particular host plants. 무료에볼루션 do not explain the fundamental changes in the body's basic plans.

Evolution by Natural Selection

The development of the myriad of living organisms on Earth is an enigma that has intrigued scientists for centuries. The most well-known explanation is Darwin's natural selection process, which occurs when better-adapted individuals survive and reproduce more effectively than those that are less well-adapted. As time passes, a group of well-adapted individuals increases and eventually forms a whole new species.

Natural selection is an ongoing process that is characterized by the interaction of three factors: variation, inheritance and reproduction. Sexual reproduction and mutation increase the genetic diversity of an animal species. Inheritance is the passing of a person's genetic traits to his or her offspring which includes both dominant and recessive alleles. Reproduction is the production of fertile, viable offspring which includes both sexual and asexual methods.

All of these factors must be in balance for natural selection to occur. If, for instance, a dominant gene allele allows an organism to reproduce and last longer than the recessive allele The dominant allele becomes more prevalent in a group. However, if the allele confers a disadvantage in survival or reduces fertility, it will be eliminated from the population. The process is self-reinforced, meaning that a species with a beneficial characteristic will survive and reproduce more than an individual with a maladaptive trait. The more offspring an organism produces, the greater its fitness which is measured by its ability to reproduce and survive. People with good characteristics, like a longer neck in giraffes, or bright white color patterns in male peacocks are more likely survive and produce offspring, which means they will make up the majority of the population over time.

Natural selection only affects populations, not on individuals. This is an important distinction from the Lamarckian theory of evolution which claims that animals acquire traits through use or neglect. For instance, if a animal's neck is lengthened by stretching to reach for prey and its offspring will inherit a longer neck. The length difference between generations will persist until the giraffe's neck gets too long to no longer breed with other giraffes.

Evolution by Genetic Drift

In genetic drift, alleles at a gene may reach different frequencies in a population through random events. At some point, only one of them will be fixed (become widespread enough to not longer be eliminated through natural selection) and the other alleles will drop in frequency. In the extreme it can lead to one allele dominance. The other alleles are essentially eliminated, and heterozygosity is reduced to zero. In a small number of people this could result in the total elimination of recessive alleles. Such a scenario would be called a bottleneck effect, and it is typical of evolutionary process that takes place when a lot of people migrate to form a new group.

A phenotypic bottleneck could happen when the survivors of a catastrophe like 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 they will all have the same phenotype and consequently have the same fitness characteristics. This situation might be caused by a conflict, earthquake or even a cholera outbreak. The genetically distinct population, if it remains susceptible to genetic drift.

Walsh, Lewens and Ariew define drift as a deviation from expected values due to differences in fitness. They give a famous example of twins that are genetically identical, share the exact same phenotype and yet one is struck by lightening and dies while the other lives and reproduces.

This type of drift can play a significant part in the evolution of an organism. However, it's not the only method to evolve. Natural selection is the primary alternative, in which mutations and migration maintain the phenotypic diversity in the population.

Stephens argues that there is a major difference between treating the phenomenon of drift as a force, or a cause and considering other causes of evolution such as selection, mutation and migration as causes or causes. He argues that a causal-process model of drift allows us to separate it from other forces and that this distinction is essential. He also argues that drift has a direction, i.e., it tends to reduce heterozygosity. It also has a size, that is determined by the size of the population.

Evolution through Lamarckism

When high school students take biology classes, they are frequently introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution is often referred to as "Lamarckism" and it asserts that simple organisms evolve into more complex organisms by the inheritance of characteristics which result from the natural activities of an organism use and misuse. Lamarckism is typically illustrated with an image of a giraffe extending its neck further to reach the higher branches in the trees. This could cause giraffes' longer necks to be passed on to their offspring who would grow taller.


Lamarck was a French zoologist and, in his lecture to begin his course on invertebrate zoology held at the Museum of Natural History in Paris on the 17th May 1802, he introduced a groundbreaking concept that radically challenged the conventional wisdom about organic transformation. According to Lamarck, living things evolved from inanimate matter through a series of gradual 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 comprehensive treatment.

The prevailing story is that Lamarckism was a rival to Charles Darwin's theory of evolution through natural selection and both theories battled out in the 19th century. Darwinism eventually won and led to the creation of what biologists refer to as the Modern Synthesis. This theory denies the possibility that acquired traits can be inherited and instead, it argues that organisms develop through the action of environmental factors, including natural selection.

While Lamarck believed in the concept of inheritance through acquired characters and his contemporaries also spoke of this idea however, it was not a major feature in any of their theories about evolution. This is due in part to the fact that it was never tested scientifically.

It's been over 200 year since Lamarck's birth and in the field of age genomics there is a growing evidence base that supports the heritability of acquired traits. It is sometimes referred to as "neo-Lamarckism" or, more frequently, epigenetic inheritance. This is a version that is as valid as the popular Neodarwinian model.

Evolution through Adaptation

One of the most common misconceptions about evolution is its being driven by a fight for survival. This is a false assumption and ignores other forces driving evolution. The struggle for existence is better described as a struggle to survive in a specific environment. This could include not only other organisms but also the physical environment itself.

Understanding how adaptation works is essential to comprehend evolution. Adaptation is any feature that allows a living organism to survive in its environment and reproduce. It could be a physiological structure such as feathers or fur or a behavioral characteristic, such as moving into the shade in hot weather or coming out at night to avoid cold.

An organism's survival depends on its ability to draw energy from the surrounding environment and interact with other living organisms and their physical surroundings. The organism should possess the right genes for producing offspring, and be able to find sufficient food and resources. Furthermore, the organism needs to be capable of reproducing at an optimal rate within its niche.

These factors, together with mutations and gene flow can cause changes in the proportion of different alleles within the population's gene pool. As time passes, this shift in allele frequencies can result in the emergence of new traits and eventually new species.

Many of the characteristics we appreciate in animals and plants are adaptations. For example lung or gills that extract oxygen from air feathers and fur for insulation long legs to run away from predators, and camouflage to hide. However, a thorough understanding of adaptation requires attention to the distinction between physiological and behavioral characteristics.

Physiological traits like thick fur and gills are physical traits. Behavior adaptations aren't like the tendency of animals to seek companionship or retreat into shade in hot weather. In addition, it is important to remember that a lack of forethought is not a reason to make something an adaptation. In fact, a failure to think about the implications of a behavior can make it unadaptable despite the fact that it may appear to be logical or even necessary.