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What is Free Evolution?

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

A variety of examples have been provided of this, including different kinds of stickleback fish that can live in salt or fresh water, as well as walking stick insect varieties that favor particular host plants. These reversible traits however, are not able to be the reason for fundamental changes in body plans.

Evolution by Natural Selection

The development of the myriad of living organisms on Earth is an enigma that has intrigued scientists for many centuries. The best-established explanation is Darwin's natural selection process, which is triggered when more well-adapted individuals live longer and reproduce more effectively than those that are less well-adapted. Over time, a population of well adapted individuals grows and eventually forms a whole new species.

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

All of these elements must be in balance to allow natural selection to take place. If, for instance an allele of a dominant gene causes an organism reproduce and last longer than the recessive gene then the dominant allele will become more common in a population. If Get Source confers a negative survival advantage or lowers the fertility of the population, it will be eliminated. This process is self-reinforcing which means that the organism with an adaptive characteristic will live and reproduce far more effectively than one with a maladaptive characteristic. The more offspring an organism can produce, the greater its fitness which is measured by its capacity to reproduce itself and live. Individuals with favorable traits, like having a long neck in the giraffe, or bright white patterns on male peacocks are more likely to others to live and reproduce, which will eventually lead to them becoming the majority.

Natural selection is a factor in populations and not on individuals. This is a major distinction from the Lamarckian theory of evolution which argues that animals acquire characteristics by use or inactivity. If a giraffe stretches its neck to reach prey and its neck gets longer, then its children will inherit this characteristic. The difference in neck size between generations will increase until the giraffe is unable to breed with other giraffes.

Evolution through Genetic Drift

Genetic drift occurs when alleles of the same gene are randomly distributed within a population. In the end, one will reach fixation (become so widespread that it can no longer be removed through natural selection), while the other alleles drop to lower frequency. This can result in dominance in extreme. The other alleles are eliminated, and heterozygosity decreases to zero. In a small number of people it could result in the complete elimination of the recessive gene. This scenario is called 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' can also occur when the survivors of a disaster such as an outbreak or mass hunt event are concentrated in the same area. The survivors will have an allele that is dominant and will share the same phenotype. This can be caused by earthquakes, war or even a plague. The genetically distinct population, if left, could be susceptible to genetic drift.

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

This kind of drift can play a very important role in the evolution of an organism. But, 에볼루션코리아 's not the only way to evolve. The main alternative is a process called natural selection, in which the phenotypic variation of a population is maintained by mutation and migration.

Stephens asserts that there is a significant difference between treating drift like an actual cause or force, and considering other causes, such as migration and selection mutation as causes and forces. He argues that a causal-process explanation of drift lets us distinguish it from other forces and that this differentiation is crucial. He also claims that drift is a directional force: that is it tends to reduce heterozygosity, and that it also has a size, that is determined by the size of the population.

Evolution by Lamarckism

When students in high school study biology they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, often referred to as "Lamarckism which means that simple organisms transform into more complex organisms taking on traits that are a product of the organism's use and misuse. Lamarckism is usually illustrated with an image of a giraffe extending its neck to reach the higher branches in the trees. This could cause the longer necks of giraffes to be passed onto their offspring who would grow taller.





Lamarck Lamarck, a French zoologist, presented a revolutionary concept in his 17 May 1802 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 an escalating series of steps. Lamarck was not the first to make this claim however he was widely regarded as the first to give the subject a thorough and general treatment.

The prevailing story is that Lamarckism was an opponent to Charles Darwin's theory of evolutionary natural selection, and that the two theories fought each other in the 19th century. Darwinism ultimately prevailed and led to what biologists call the Modern Synthesis. This theory denies that acquired characteristics can be acquired through inheritance and instead suggests that organisms evolve by the symbiosis of environmental factors, such as natural selection.

While Lamarck supported the notion of inheritance by acquired characters and his contemporaries offered a few words about this idea however, it was not a major feature in any of their evolutionary theories. This is largely due to the fact that it was never validated scientifically.

It has been more than 200 years since the birth of Lamarck and in the field of genomics there is a growing evidence-based body of evidence to support the heritability acquired characteristics. This is also referred to as "neo Lamarckism", or more often epigenetic inheritance. This is a model that is as valid as the popular neodarwinian model.

Evolution through Adaptation

One of the most popular misconceptions about evolution is being driven by a struggle to survive. This notion is not true and overlooks other forces that drive evolution. The struggle for survival is more effectively described as a struggle to survive within a particular environment, which could be a struggle that involves not only other organisms, but as well the physical environment.

To understand how evolution operates it is important to consider what adaptation is. The term "adaptation" refers to any specific characteristic that allows an organism to survive and reproduce in its environment. It could be a physical structure, such as feathers or fur. It could also be a characteristic of behavior, like moving to the shade during the heat, or moving out to avoid the cold at night.

The capacity of an organism to draw energy from its environment and interact with other organisms as well as their physical environment, is crucial to its survival. The organism must possess the right genes for producing offspring and to be able to access sufficient food and resources. The organism must be able to reproduce itself at a rate that is optimal for its specific niche.

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

Many of the characteristics we admire about animals and plants are adaptations, for example, lung or gills for removing oxygen from the air, feathers or fur to protect themselves long legs to run away from predators, and camouflage to hide. However, a proper understanding of adaptation requires a keen eye to the distinction between the physiological and behavioral characteristics.

Physical traits such as thick fur and gills are physical characteristics. Behavioral adaptations are not, such as the tendency of animals to seek out companionship or retreat into shade in hot weather. Furthermore it is important to note that a lack of thought does not make something an adaptation. A failure to consider the effects of a behavior even if it appears to be rational, could make it unadaptive.