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What is Free Evolution?

Free evolution is the concept that natural processes can cause organisms to develop over time. This includes the appearance and growth of new species.

Many examples have been given of this, including various varieties of stickleback fish that can be found in salt or fresh water, and walking stick insect varieties that prefer particular host plants. These mostly reversible traits permutations cannot explain fundamental changes to the basic body plan.

Evolution by Natural Selection

The development of the myriad living creatures on Earth is a mystery that has intrigued scientists for many centuries. Charles Darwin's natural selection is the most well-known explanation. This process occurs when people who are more well-adapted are able to reproduce faster and longer than those who are less well-adapted. Over time, the population of well-adapted individuals grows and eventually develops into a new species.

Natural selection is a process that is cyclical and involves the interaction of three factors including reproduction, variation and inheritance. Sexual reproduction and mutation increase genetic diversity in the species. Inheritance is the term used to describe the transmission of a person's genetic characteristics, which includes recessive and dominant genes, to their offspring. Reproduction is the process of generating viable, fertile offspring. This can be done by both asexual or sexual methods.


All of these variables have to be in equilibrium to allow natural selection to take place. For instance when a dominant allele at the gene causes an organism to survive and reproduce more frequently than the recessive allele the dominant allele will be more prevalent within the population. If the allele confers a negative advantage to survival or reduces the fertility of the population, it will disappear. This process is self-reinforcing meaning that an organism that has an adaptive characteristic will live and reproduce far more effectively than those with a maladaptive feature. The more offspring that an organism has the better its fitness, which is measured by its ability to reproduce itself and survive. People with good characteristics, such as a long neck in Giraffes, or the bright white color patterns on male peacocks are more likely to others to live and reproduce and eventually lead to them becoming the majority.

Natural selection is only an aspect of populations and not on individuals. This is a significant distinction from the Lamarckian theory of evolution, which states that animals acquire traits through the use or absence of use. If a giraffe extends its neck to catch prey, and the neck becomes longer, then the children will inherit this characteristic. The difference in neck size between generations will continue to increase until the giraffe is unable to reproduce with other giraffes.

Evolution through Genetic Drift

In genetic drift, the alleles at a gene may attain different frequencies in a population through random events. In the end, one will reach fixation (become so widespread that it is unable to be removed through natural selection) and the other alleles drop to lower frequency. This can lead to a dominant allele in extreme. The other alleles are virtually eliminated and heterozygosity diminished to a minimum. In a small number of people this could lead to the complete elimination of recessive gene. This is known as the bottleneck effect and is typical of the evolutionary process that occurs whenever the number of individuals migrate to form a group.

A phenotypic bottleneck can also occur when the survivors of a catastrophe such as an outbreak or mass hunt incident are concentrated in an area of a limited size. The survivors will have a dominant allele and thus will have the same phenotype. This could be caused by war, earthquakes or even a plague. Whatever the reason the genetically distinct population that is left might be prone to genetic drift.

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

This type of drift is very important in the evolution of the species. However, it's not the only method to progress. The main alternative is a process called natural selection, in which the phenotypic diversity of a population is maintained by mutation and migration.

Stephens argues that there is a major distinction between treating drift as a force, or a cause and considering other causes of evolution such as selection, mutation, and migration as forces or causes. He argues that a causal mechanism account of drift allows us to distinguish it from the other forces, and that this distinction is essential. He further argues that drift is a directional force: that is it tends to eliminate heterozygosity, and that it also has a magnitude, that is determined by the size of the population.

Evolution by Lamarckism

Biology students in high school are frequently introduced to Jean-Baptiste Lemarck's (1744-1829) work. His theory of evolution, often referred to as "Lamarckism is based on the idea that simple organisms transform into more complex organisms inheriting characteristics that are a product of an organism's use and disuse. Lamarckism can be demonstrated by a giraffe extending its neck to reach higher branches in the trees. This would cause the longer necks of giraffes to be passed to their offspring, who would then become taller.

???? ??? from France, presented an idea that was revolutionary in his 17 May 1802 opening lecture at the Museum of Natural History of Paris. He challenged the traditional thinking about organic transformation. According Lamarck, living organisms evolved from inanimate matter through a series gradual steps. Lamarck was not the only one to suggest that this could be the case, but his reputation is widely regarded as giving the subject its first broad and thorough treatment.

The most popular story is that Charles Darwin's theory of evolution by natural selection and Lamarckism fought in the 19th Century. Darwinism eventually prevailed, leading to what biologists refer to as the Modern Synthesis. The theory argues that acquired traits can be passed down through generations and instead, it claims that organisms evolve through the selective action of environment elements, like Natural Selection.

Lamarck and his contemporaries believed in the idea that acquired characters could be passed down to the next generation. However, this idea was never a central part of any of their theories about evolution. This is due in part to the fact that it was never tested scientifically.

It's been more than 200 years since Lamarck was born and in the age of genomics there is a huge amount of evidence that supports the heritability of acquired traits. This is also referred to as "neo Lamarckism", or more commonly epigenetic inheritance. This is a version that is just as valid as the popular Neodarwinian model.

Evolution through adaptation

One of the most common misconceptions about evolution is being driven by a struggle for survival. In fact, this view is a misrepresentation of natural selection and ignores the other forces that are driving evolution. The struggle for survival is more effectively described as a struggle to survive within a specific environment, which could include not just other organisms, but as well the physical environment.

To understand how evolution works it is important to understand what is adaptation. It refers to a specific characteristic that allows an organism to survive and reproduce within its environment. It could be a physical feature, like feathers or fur. Or it can be a behavior trait that allows you to move to the shade during the heat, or escaping the cold at night.

The ability of an organism to draw energy from its surroundings and interact with other organisms as well as their physical environments, is crucial to its survival. The organism needs to have the right genes to generate offspring, and must be able to locate sufficient food and other resources. The organism must be able to reproduce at the rate that is suitable for its particular niche.

These factors, together with mutations and gene flow can cause a shift in the proportion of different alleles in a population’s gene pool. This shift in the frequency of alleles can lead to the emergence of new traits, and eventually, new species as time passes.

Many of the features we find appealing in animals and plants are adaptations. For example the lungs or gills which extract oxygen from air feathers and fur as insulation, long legs to run away from predators and camouflage to conceal. However, a complete understanding of adaptation requires attention to the distinction between behavioral and physiological characteristics.

Physical traits such as thick fur and gills are physical characteristics. Behavioral adaptations are not like the tendency of animals to seek out companionship or to retreat into the shade in hot weather. Furthermore it is important to remember that lack of planning is not a reason to make something an adaptation. In fact, failing to think about the consequences of a behavior can make it unadaptive even though it may appear to be logical or even necessary.

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