"Mutational Bias" questions NeoDarwinian "random" Mutations

Neo-Darwinism, also known as the modern synthesis, is the prevailing explanation of how evolution works. It is based on the idea that evolution is driven by natural selection, which acts on genetic variation in a population.

Mutational bias is the tendency for certain types of mutations to occur more often than others. This can be due to a variety of factors, such as the chemical properties of DNA, the way that DNA is replicated, or the environment in which cells are growing.

Neo-Darwinism does not predict mutational bias because it assumes that mutations are random. This means that there is no reason to expect that certain types of mutations would occur more often than others.

However, recent research has shown that mutational bias is a real phenomenon. This has led some scientists to argue that neo-Darwinism needs to be modified to take into account mutational bias. This is a problem as random mutations are a 100 year axiom of NeoDarwinism. Replacement of Neo Darwinism is seriously being considered.


This article "The Role of Mutation Bias in Adaptive Evolution" by Erik Svensson and David Berger explores why.

Mutation is the ultimate source of genetic variation in populations. Mutations can be either beneficial, neutral, or harmful. Beneficial mutations can lead to adaptive evolution, while harmful mutations can be selected against. Neutral mutations have no effect on fitness and are therefore more likely to accumulate in populations over time.

Mutation bias is the phenomenon whereby some types of mutations are more likely to occur than others. Mutation bias can be caused by a variety of factors, including the structure of DNA, the environment, and the cell's repair mechanisms.

Mutation bias can play a role in adaptive evolution in a number of ways. First, mutation bias can increase the rate of adaptive evolution by providing more beneficial mutations. Second, mutation bias can direct the course of adaptive evolution by favoring mutations that are more likely to be beneficial. Third, mutation bias can help to overcome genetic constraints on adaptation by providing mutations that can bypass these constraints.

There is a growing body of evidence that mutation bias can play a role in adaptive evolution. For example, studies of bacteria have shown that mutation bias can increase the rate of adaptation to antibiotic resistance. Studies of plants have shown that mutation bias can direct the course of adaptation to changing environments. And studies of animals have shown that mutation bias can help to overcome genetic constraints on adaptation.

Theoretical models have also been used to investigate the role of mutation bias in adaptive evolution. These models have shown that mutation bias can have a significant impact on the rate and direction of adaptive evolution. However, the precise role of mutation bias in adaptive evolution is still a matter of debate.

Mutation bias is a complex phenomenon that can have a significant impact on adaptive evolution. The role of mutation bias in adaptive evolution is still a matter of debate, but there is growing evidence that it can play a major role in shaping the evolution of populations.

In addition to the above, here are some other important points from the article:

  • Mutation bias can be either directional or non-directional. Directional mutation bias refers to the situation where some types of mutations are more likely to occur than others, while non-directional mutation bias refers to the situation where all types of mutations are equally likely to occur.

  • The strength of mutation bias can vary depending on the organism and the environment. In some cases, mutation bias can be very strong, while in other cases it can be very weak.

  • Mutation bias can be affected by a variety of factors, including the structure of DNA, the environment, and the cell's repair mechanisms.

  • The role of mutation bias in adaptive evolution is still a matter of debate. However, there is growing evidence that it can play a major role in shaping the evolution of population.

Standard evolutionary theory recognizes only one force (natural selection) that can lead to directional evolutionary change towards increased organismal adaptation.

Critics of standard evolutionary theory have argued that mutational bias is an alternative evolutionary process or cause that can increase organismal adaptation independently of natural selection.

Mutational input is the ultimate source of genetic variation, but NeoDarwinian random mutations are not thought to affect the direction of adaptive evolution.

Recently, critics of standard evolutionary theory have questioned the random and non-directional nature of mutations.

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