What is Free Evolution?

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

Many examples have been given of this, including various varieties of fish called sticklebacks that can live in either salt or fresh water, and walking stick insect varieties that are attracted to specific host plants. These typically reversible traits are not able to explain fundamental changes to basic body plans.

Evolution by Natural Selection

Scientists have been fascinated by the evolution of all the living creatures that inhabit our planet for many centuries. Charles Darwin's natural selection theory is the most well-known explanation. This process occurs when individuals who are better-adapted have more success in reproduction and survival than those who are less well-adapted. Over time, a community of well-adapted individuals increases and eventually creates a new species.

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

All of these factors must be in harmony for natural selection to occur. If, for instance an allele of a dominant gene allows an organism to reproduce and live longer than the recessive gene allele then the dominant allele will become more common in a population. If the allele confers a negative advantage to survival or decreases the fertility of the population, it will go away. The process is self-reinforcing meaning that an organism that has an adaptive characteristic will live and 무료에볼루션 reproduce far more effectively than those with a maladaptive feature. The greater an organism's fitness, measured by its ability reproduce and survive, is the greater number of offspring it will produce. People with desirable traits, such as having a longer neck in giraffes, or bright white color patterns in male peacocks are more likely be able to survive and create offspring, which means they will become the majority of the population over time.

Natural selection is only a force for populations, not on individual organisms. This is a major distinction from the Lamarckian theory of evolution which holds that animals acquire traits through usage or inaction. If a giraffe extends its neck to catch prey and the neck grows larger, then its children will inherit this characteristic. The differences in neck size between generations will increase until the giraffe is no longer able to breed with other giraffes.

Evolution by Genetic Drift

Genetic drift occurs when alleles of the same gene are randomly distributed in a population. In the end, only one will be fixed (become widespread enough to not more be eliminated through natural selection) and the other alleles drop in frequency. This can result in a dominant allele in extreme. The other alleles are essentially eliminated, and heterozygosity decreases to zero. In a small number of people, this could lead to the total elimination of the recessive allele. This scenario is called the bottleneck effect and is typical of an evolutionary process that occurs whenever a large number individuals migrate to form a group.

A phenotypic bottleneck could occur when survivors of a catastrophe like an epidemic or a mass hunting event, are condensed in a limited area. The survivors will be mostly homozygous for the dominant allele, meaning that they all share the same phenotype and will thus share the same fitness characteristics. This may be caused by conflict, earthquake, or even a plague. Whatever the reason the genetically distinct group that remains could be susceptible to genetic drift.

Walsh Lewens, Walsh and Ariew define drift as a deviation from expected values due to differences in fitness. They provide a well-known instance of twins who are genetically identical, have identical phenotypes but one is struck by lightening and dies while the other lives and reproduces.

This kind of drift can play a very important part in the evolution of an organism. But, it's not the only method to evolve. Natural selection is the primary alternative, where mutations and migration maintain phenotypic diversity within the population.

Stephens argues there is a significant difference between treating drift like an agent or cause and considering other causes, such as migration and selection as causes and forces. Stephens claims that a causal process explanation of drift allows us to distinguish it from other forces, and this distinction is crucial. He also argues that drift has both a direction, i.e., it tends towards eliminating heterozygosity. It also has a size, which is determined based on the size of the population.

Evolution through Lamarckism

In high school, students take biology classes, they are frequently introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, often called "Lamarckism, states that simple organisms evolve into more complex organisms adopting traits that are a product of the organism's use and misuse. Lamarckism can be demonstrated by a giraffe extending its neck to reach higher levels of leaves in the trees. This could cause giraffes to give their longer necks to their offspring, who would then get taller.

Lamarck Lamarck, a French Zoologist, introduced a revolutionary concept in his 17 May 1802 opening lecture at the Museum of Natural History of Paris. He challenged the conventional wisdom on organic transformation. According to him living things had evolved from inanimate matter via the gradual progression of events. Lamarck was not the first to suggest that this might be the case, but his reputation is widely regarded as having given the subject its first broad and comprehensive analysis.

The popular narrative is that Lamarckism became a rival to Charles Darwin's theory of evolutionary natural selection and that the two theories fought each other in the 19th century. Darwinism eventually won and led to the creation of what biologists refer to as the Modern Synthesis. This theory denies that traits acquired through evolution can be inherited and instead suggests that organisms evolve by the symbiosis of environmental factors, including natural selection.

While Lamarck endorsed the idea of inheritance by acquired characters and his contemporaries spoke of this idea, it was never a central element in any of their evolutionary theories. This is partly due to the fact that it was never validated scientifically.

It's been more than 200 years since Lamarck was born and in the age of genomics there is a vast amount of evidence that supports the heritability of acquired characteristics. This is often referred to as "neo-Lamarckism" or more commonly epigenetic inheritance. This is a version that is as reliable as the popular neodarwinian model.

Evolution through the process of adaptation

One of the most popular misconceptions about evolution is that it is driven by a type of struggle to survive. This is a false assumption and overlooks other forces that drive evolution. The fight for survival can be more accurately described as a struggle to survive in a certain environment. This can include not just other organisms as well as the physical surroundings themselves.

To understand how evolution works it is beneficial to understand what is adaptation. Adaptation refers to any particular characteristic that allows an organism to survive and reproduce within its environment. It can be a physiological feature, such as feathers or fur or a behavior like moving to the shade during hot weather or coming out at night to avoid the 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 have the right genes to create offspring and to be able to access sufficient food and resources. The organism must also be able reproduce itself at an amount that is appropriate for its niche.

These factors, along with mutation and gene flow result in a change in the proportion of alleles (different types of a gene) in the population's gene pool. This change in allele frequency could lead to the development of new traits, and eventually, new species in the course of 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 and long legs for running away from predators and camouflage for hiding. To understand adaptation it is essential to differentiate between physiological and behavioral characteristics.

Physiological adaptations like thick fur or gills are physical traits, whereas behavioral adaptations, such as the desire to find companions or to move into the shade in hot weather, aren't. Additionally it is important to understand that a lack of thought is not a reason to make something an adaptation. In fact, failure to think about the implications of a decision can render it unadaptive despite the fact that it appears to be logical or even necessary.