15 Best Documentaries On Free Evolution

What is Free Evolution?

Free evolution is the idea that the natural processes that organisms go through can cause them to develop over time. This includes the appearance and development of new species.

This has been demonstrated by numerous examples such as the stickleback fish species that can live in salt or fresh water, and walking stick insect species that are apprehensive about particular host plants. These reversible traits however, are not able to explain fundamental changes in basic body plans.

Evolution by Natural Selection

Scientists have been fascinated by the evolution of all living creatures that live on our planet for centuries. Charles Darwin's natural selection theory is the best-established explanation. This is because those who are better adapted have more success in reproduction and survival than those who are less well-adapted. Over time, the population of well-adapted individuals becomes larger and eventually forms an entirely new species.

Natural selection is an ongoing process and involves the interaction of 3 factors including reproduction, variation and inheritance. Mutation and sexual reproduction increase the genetic diversity of a species. Inheritance refers to the passing of a person's genetic traits to their offspring, which includes both recessive and dominant alleles. Reproduction is the process of producing fertile, viable offspring, which includes both sexual and asexual methods.

All of these elements must be in harmony to allow natural selection to take place. If, for example, a dominant gene allele makes an organism reproduce and live longer than the recessive allele The dominant allele becomes more prevalent in a group. If the allele confers a negative advantage to survival or reduces the fertility of the population, it will go away. The process is self-reinforcing, meaning that a species with a beneficial trait can reproduce and survive longer than an individual with an inadaptive characteristic. The higher the level of fitness an organism has, measured by its ability reproduce and survive, is the greater number of offspring it produces. People with good characteristics, such as having a long neck in Giraffes, or the bright white color patterns on male peacocks are more likely than others to survive and reproduce which eventually leads to them becoming the majority.

Natural selection only acts on populations, not on individuals. This is a major distinction from the Lamarckian theory of evolution, which states that animals acquire characteristics by use or inactivity. For instance, if a animal's neck is lengthened by stretching to reach prey its offspring will inherit a larger neck. The differences in neck length between generations will continue until the giraffe's neck gets too long that it can not breed with other giraffes.

Evolution through Genetic Drift

In genetic drift, the alleles of a gene could reach different frequencies in a population due to random events. At some point, only one of them will be fixed (become common enough that it can no longer be eliminated through natural selection), and the other alleles decrease in frequency. In the extreme this, it leads to dominance of a single allele. The other alleles are eliminated, and heterozygosity decreases to zero. In a small number of people this could result in the complete elimination of recessive alleles. Such a scenario would be called a bottleneck effect, and it is typical of the kind of evolutionary process that takes place when a large amount of people migrate to form a new group.

A phenotypic bottleneck can also occur when the survivors of a disaster such as an epidemic or a mass hunting event, are condensed within a narrow area. The survivors will carry a dominant allele and thus will have the same phenotype. This could be caused by earthquakes, war or even a plague. The genetically distinct population, if it is left, could be susceptible to genetic drift.

Walsh, Lewens, and Ariew utilize a "purely outcome-oriented" definition of drift as any deviation from the expected values of variations in fitness. They give the famous example of twins who are both genetically identical and have exactly the same phenotype, but one is struck by lightning and dies, while the other lives to reproduce.

This kind of drift can be vital to the evolution of a species. It's not the only method of evolution. The main alternative is to use a process known as natural selection, in which the phenotypic diversity of a population is maintained by mutation and migration.

Stephens claims that there is a significant difference between treating the phenomenon of drift as a force or as a cause and treating other causes of evolution such as selection, mutation, and migration as forces or causes. He claims that a causal mechanism account of drift permits us to differentiate it from the other forces, and that this distinction is essential. He also argues that drift has a direction, that is it tends to eliminate heterozygosity, and that it also has a specific magnitude 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, commonly called "Lamarckism, states that simple organisms develop into more complex organisms taking on traits 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 giraffes to give their longer necks to their offspring, who would then grow even taller.

Lamarck was a French zoologist and, in his opening lecture for his course on invertebrate zoology held at the Museum of Natural History in Paris on the 17th of May in 1802, he presented an innovative concept that completely challenged the previous understanding of organic transformation. According Lamarck, living organisms evolved from inanimate material by a series of gradual steps. Lamarck was not the only one to suggest that this might be the case, but he is widely seen as being the one who gave the subject its first broad and comprehensive treatment.

The most popular story is that Lamarckism became an opponent to Charles Darwin's theory of evolution through natural selection, and that the two theories battled out in the 19th century. Darwinism eventually triumphed and led to the creation of what biologists refer to as the Modern Synthesis. The Modern Synthesis theory denies that acquired characteristics can be inherited and instead, it argues that organisms develop through the selective action of environmental factors, like natural selection.

While Lamarck endorsed the idea of inheritance through acquired characters and his contemporaries spoke of this idea however, it was not an integral part of any of their evolutionary theories. This is due in part to the fact that it was never validated scientifically.

It has been more than 200 year since Lamarck's birth and in the field of age genomics, there is a growing evidence-based body of evidence to support the heritability acquired characteristics. This is also known as "neo Lamarckism", or more commonly epigenetic inheritance. It is a version of evolution that is just as relevant as the more popular neo-Darwinian model.

Evolution by the process of adaptation

One of the most widespread misconceptions about evolution is that it is driven by a type of struggle for survival. In 에볼루션 룰렛 , this view 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 specific environment, which may include not just other organisms, but also the physical environment.

Understanding how adaptation works is essential to comprehend evolution. Adaptation is any feature that allows a living thing to live in its environment and reproduce. It could be a physiological structure such as fur or feathers, or a behavioral trait such as a tendency to move into shade in the heat or leaving at night to avoid cold.

The capacity of an organism to extract energy from its environment and interact with other organisms as well as their physical environments is essential to its survival. The organism must possess the right genes to produce offspring, and must be able to locate sufficient food and other resources. The organism should be able to reproduce itself at the rate that is suitable for its particular niche.

These elements, along with mutations and gene flow can cause an alteration in the ratio of different alleles within a population’s gene pool. The change in frequency of alleles can lead to the emergence of novel traits and eventually, new species over time.

Many of the features that we admire about animals and plants are adaptations, such as the lungs or gills that extract oxygen from the air, fur or feathers to provide insulation long legs to run away from predators and camouflage to hide. However, a complete understanding of adaptation requires attention to the distinction between physiological and behavioral characteristics.

Physical traits such as large gills and thick fur are physical traits. Behavioral adaptations are not, such as the tendency of animals to seek companionship or to retreat into the shade during hot temperatures. It is also important to remember that a insufficient planning does not result in an adaptation. A failure to consider the implications of a choice even if it seems to be rational, may make it inflexible.