What is Free Evolution?

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

Numerous examples have been offered of this, such as different varieties of stickleback fish that can live in fresh or salt water and walking stick insect varieties that favor specific host plants. These mostly reversible trait permutations can't, however, be the reason for fundamental changes in body plans.

Evolution through Natural Selection

The development of the myriad of living creatures on Earth is a mystery that has intrigued scientists for centuries. The best-established explanation is Charles Darwin's natural selection, an evolutionary process that occurs when individuals that are better adapted survive and reproduce more successfully than those less well adapted. As time passes, the number of well-adapted individuals grows and eventually forms a new species.

Natural selection is a cyclical process that is characterized by the interaction of three factors including inheritance, variation, and reproduction. Variation is caused by mutations and sexual reproduction both of which increase the genetic diversity within the species. Inheritance refers the transmission of a person’s genetic characteristics, which includes recessive and dominant genes, to their offspring. Reproduction is the process of producing fertile, viable offspring, which includes both sexual and asexual methods.

All of these elements must be in balance for natural selection to occur. If, for instance an allele of a dominant gene allows an organism to reproduce and survive more than the recessive gene allele, then the dominant allele becomes more common in a population. However, if the allele confers a disadvantage in survival or reduces fertility, it will be eliminated from the population. The process is self-reinforced, which means that an organism with a beneficial trait is more likely to survive and reproduce than an individual with an unadaptive trait. The more offspring an organism can produce the better its fitness which is measured by its ability to reproduce and survive. People with desirable characteristics, like having a longer neck in giraffes, or bright white colors in male peacocks, are more likely to survive and have offspring, and thus will eventually 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 which holds that animals acquire traits either through usage or inaction. For example, if a Giraffe's neck grows longer due to reaching out to catch prey and its offspring will inherit a more long neck. The differences in neck size between generations will increase until the giraffe is unable to breed with other giraffes.

Evolution through Genetic Drift

In genetic drift, alleles of a gene could attain different frequencies in a population by chance events. At some point, only one of them will be fixed (become common enough to no more be eliminated through natural selection), and the other alleles drop in frequency. In extreme cases this, it leads to dominance of a single allele. The other alleles have been virtually eliminated and heterozygosity been reduced to a minimum. In a small population it could result in the complete elimination of recessive gene. This is called a bottleneck effect, and it is typical of evolutionary process that takes place when a large amount of people migrate to form a new population.

A phenotypic bottleneck could happen when the survivors of a disaster like an epidemic or a mass hunting event, are condensed in a limited area. The survivors will carry an allele that is dominant and will have the same phenotype. This could be caused by earthquakes, war or even a plague. The genetically distinct population, if it remains susceptible to genetic drift.

Walsh Lewens, Walsh and Ariew define drift as a deviation from the expected value due to differences in fitness. 에볼루션 사이트 give the famous example of twins that are genetically identical and share the same phenotype. However, one is struck by lightning and dies, but the other continues to reproduce.

This type of drift can play a crucial role in the evolution of an organism. However, it is not the only way to develop. The primary alternative is a process called natural selection, in which the phenotypic diversity of a population is maintained by mutation and migration.

Stephens claims that there is a vast difference between treating the phenomenon of drift as a force or cause, and considering other causes, such as selection mutation and migration as forces and causes. He argues that a causal process explanation of drift permits us to differentiate it from the other forces, and this distinction is vital. He also argues that drift has an orientation, i.e., it tends to reduce heterozygosity. It also has a size, which is determined based on population size.

Evolution by 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 often referred to as "Lamarckism" and it asserts that simple organisms evolve into more complex organisms by the inherited characteristics that result from an organism's natural activities, use and disuse. Lamarckism can be demonstrated by the giraffe's neck being extended to reach higher levels of leaves in the trees. This would cause giraffes to give their longer necks to offspring, which then get taller.

Lamarck the French Zoologist from France, presented an idea that was revolutionary in his opening lecture at the Museum of Natural History of Paris. He challenged the traditional thinking about organic transformation. In his opinion, living things had evolved from inanimate matter via a series of gradual steps. Lamarck was not the first to make this claim, but he was widely regarded as the first to give the subject a thorough and general explanation.


The most popular story is that Lamarckism grew into an opponent to Charles Darwin's theory of evolutionary natural selection and that the two theories battled it out in the 19th century. Darwinism ultimately prevailed and led to what biologists refer to as the Modern Synthesis. This theory denies acquired characteristics can be passed down and instead argues that organisms evolve through the selective influence of environmental elements, like Natural Selection.

Although Lamarck believed in the concept of inheritance through acquired characters, and his contemporaries also paid lip-service to this notion however, it was not a major feature in any of their evolutionary theorizing. This is due in part to the fact that it was never tested scientifically.

It's been more than 200 year since Lamarck's birth and in the field of age genomics, there is an increasing body of evidence that supports the heritability of acquired traits. This is sometimes referred to as "neo-Lamarckism" or more often, epigenetic inheritance. This is a variant that is just as valid as the popular Neodarwinian model.

Evolution by adaptation

One of the most common misconceptions about evolution is that it is being driven by a fight for survival. In reality, this notion is inaccurate and overlooks the other forces that drive evolution. The fight for survival can be more precisely described as a fight to survive within a particular environment, which may involve not only other organisms but also the physical environment itself.

To understand how evolution works it is important to think about what adaptation is. The term "adaptation" refers to any characteristic that allows a living organism to survive in its environment and reproduce. It can be a physiological structure such as fur or feathers or a behavior, such as moving to the shade during hot weather or stepping out at night to avoid cold.

The ability of a living thing to extract energy from its surroundings and interact with other organisms and their physical environments, 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 also be able reproduce itself at an amount that is appropriate for its niche.

These factors, in conjunction with mutations and gene flow can cause a shift in the proportion of different alleles in the gene pool of a population. As time passes, this shift in allele frequency can result in the emergence of new traits and ultimately new species.

A lot of the traits we admire about animals and plants are adaptations, like lung or gills for removing oxygen from the air, feathers or fur to protect themselves, long legs for running away from predators, and camouflage to hide. To understand adaptation it is crucial to discern between physiological and behavioral traits.

Physical traits such as the thick fur and gills are physical characteristics. Behavior adaptations aren't, such as the tendency of animals to seek out companionship or move into the shade in hot temperatures. In addition it is important to note that a lack of thought is not a reason to make something an adaptation. A failure to consider the effects of a behavior even if it seems to be rational, could make it unadaptive.