Epigenetic Seasonal changes challenges NeoDarwinism


The journal article "Epigenetics and seasonal timing in animals: a concise review" explores the recent advances in understanding how epigenetics plays a role in seasonal adaptation in animals. Epigenetic mechanisms are heritable changes in gene expression that do not involve changes in the DNA sequence itself as opposed to NeoDarwinism. Epigenetic factors can be influenced by the environment, and they can be passed down from parents to offspring.

Seasonal adaptation in animals is the ability of animals to adjust their biology and behavior to match the changing seasons. This includes changes in things like migration, reproduction, and fur color. Seasonal adaptation is important for animals because it allows them to adapt and reproduce in their environment. NeoDarwinism reacts to the here and now and does not take seasons into account. A beneficial mutation that occurs in the winter would only be selective for winter not summer. Therefore NeoDarwinism would not be flexible for all seasons. In addition it occurs over vast times not in just one season.

The review article by Luo et al. (2023) discusses how epigenetic mechanisms are involved in regulating seasonal cycles in animals. The authors focus on three main epigenetic mechanisms: DNA methylation, histone modifications, and non-coding RNA.

DNA methylation:

DNA methylation is the addition of a methyl group to a DNA molecule. This can alter the way that genes are expressed. For example, DNA methylation can silence a gene, preventing it from being transcribed into RNA. This is outside of NeoDarwinism.

DNA methylation has been shown to play a role in seasonal timing in a variety of animals. For example, in Siberian hamsters, DNA methylation patterns change in the brain in response to changes in day length. These changes in DNA methylation are thought to contribute to the hamsters' seasonal changes in behavior, such as their increased activity during the winter months.

Histone modifications:

Histone modifications are chemical changes that can be made to histone proteins. Histones are proteins that package DNA into chromosomes. Histone modifications can affect how tightly DNA is packaged, which can influence gene expression.

Histone modifications have also been shown to play a role in seasonal timing in animals. For example, in birds, histone modifications change in the brain in response to changes in day length. These changes in histone modifications are thought to contribute to the birds' seasonal changes in behavior, such as their singing and mating behavior.

Non-coding RNA:

Non-coding RNA is RNA that is not translated into proteins. Non-coding RNA can regulate gene expression in a variety of ways.

Non-coding RNA has also been shown to play a role in seasonal timing in animals. For example, in insects, non-coding RNA is involved in regulating the expression of genes that are involved in diapause, a state of dormancy that insects use to survive the winter. NeoDarwinism by definition does not act on noncoding DNA which codes for noncoding RNA. NeoDarwinism acts on coding DNA which gives rise to different proteins/phenotypes for natural selection to act on.

Challenges to Neo Darwinism:

Neo Darwinism is the modern theory of evolution, which is based on the principles of natural selection and genetic inheritance. Neodarwinism explains how populations of organisms change over time through the process of natural selection.

Seasonal adaptation in animals is a complex trait that is influenced by a variety of factors, including genetics, epigenetics, and the environment. Epigenetic mechanisms allow animals to adapt to seasonal changes without having to undergo changes in their DNA sequence itself as per NeoDarwinism.

This raises a challenge for neo-Darwinismm, which is based on the idea that evolution is driven by changes in DNA sequence. Epigenetic changes can be heritable, but they are not encoded in the DNA sequence.

Epigenetic changes can be passed down to offspring through non-sexual mechanisms, such as through the cytoplasm of the egg cell. This means that epigenetic changes can play a role in evolution, even though they are not encoded in the DNA sequence as per NeoDarwinism.

Overall, the journal article by Luo et al. (2023) provides a comprehensive overview of the recent advances in understanding how epigenetics plays a role in seasonal adaptation in animals. The authors discuss the three main epigenetic mechanisms that are involved in seasonal timing: DNA methylation, histone modifications, and non-coding RNA.

The fact that epigenetic mechanisms can play a role in seasonal adaptation without having to involve changes in DNA sequence raises a challenge for neo darwinism. Epigenetic changes can be passed down to offspring through non-sexual mechanisms, which means that they can play a role in evolution.

Conclusion:

The journal article by Luo et al. (2023) is an important contribution to our understanding of the role of epigenetics in seasonal adaptation in animals. The authors provide a comprehensive overview of the recent advances in this field, and they discuss the challenges that seasonal timing poses for neodarwinism.

More research is needed to fully understand how epigenetic mechanisms are involved in seasonal timing and evolution. However, the work by Luo et al. (2023) provides a solid foundation for future research in this area.

Comments

Post a Comment

Popular posts from this blog

Beyond the Sequence: The Epigenetic "Fingers" That Play the DNA Keyboard

Image
Imagine the keyboard itself is not a standard piano keyboard, but a modular synthesizer, capable of producing an almost infinite array of sounds. The DNA sequence, then, represents the fundamental building blocks of this synthesizer, the raw materials from which all sounds are generated. Epigenetics, our "fingers," manipulates these building blocks, adjusting parameters like volume, timbre, and rhythm, transforming the raw potential of the DNA sequence into a symphony of cellular functions. We can further refine the "fingers" analogy. Consider that each finger represents a distinct epigenetic mechanism: DNA methylation, histone modifications, and non-coding RNA.  DNA methylation, for instance, might be the "index finger," capable of precisely silencing specific genes, like muting individual keys on the synthesizer. Histone modifications, the "middle finger," could represent the ability to adjust the accessibility of the DN...
Read more

Rewriting the Rules: Epigenomic Mutation Bias Challenges Randomness in Evolution

Image
This research challenges the long-held dogma that mutations occur randomly, irrespective of their consequences, by demonstrating a clear, epigenome-mediated mutation bias in Arabidopsis thaliana . The study meticulously unveils how mutation rates are not uniform across the genome but are significantly reduced in functionally constrained regions, particularly within gene bodies and essential genes. This discovery fundamentally alters our understanding of evolutionary processes, suggesting that mutation is not a purely directionless force. "Mutation bias reflects natural selection in Arabidopsis thaliana" This opening statement encapsulates the core finding: mutation rates are not random but reflect epigenetic pressures. The authors demonstrate that mutations are less frequent in crucial genomic regions, directly contradicting the prevailing theory of random mutation. This observation suggests an active mechanism that minimizes deleterious mutations in essentia...
Read more

Why are Christian philosophers running towards Darwin while biologists are "running" away?

Image
As nature reveals the strength of epigenetics and the weakness of Neo-Darwinism, biologists are “running” away from the long-standing accepted theory. In The Federalist , April 2019, Benjamin Dierker reviews “Why one-third of biologists now question Darwinism”: "Current estimates are that approximately one-third of professional academic biologists who do not believe in intelligent design find Darwin’s Theory inadequate to describe all of the complexity in biology.” Dierker continues, “The important note is that these are not ideologues or religious zealots, nor do they propose a god or biblical solution.  Rather, they find problems in the lack of explanatory power of Darwin’s theory in light of modern understanding of mutation, variation, DNA sequencing and more. These expressions of doubt do not reject naturalism or evolution per se, but the rigor of the Neo-Darwinian model for explaining the development of life.” For 40 years, scientists calculated natural se...
Read more