Posts

GC-Biased Gene Conversion and Ultraconserved Elements

Image
GC-biased gene conversion (gBGC) is a non-adaptive evolutionary process that favors the transmission of guanine (G) and cytosine (C) nucleotides over adenine (A) and thymine (T) during DNA repair. This bias can lead to an increase in the GC content of a genomic region over time, even in the absence of selective pressure. Recent research has revealed a fascinating connection between gBGC and the evolution of ultraconserved elements (UCEs), shedding light on the complex interplay between adaptive and non-adaptive forces in shaping genomic diversity. UCEs are stretches of DNA that exhibit extraordinary levels of conservation across distantly related species, suggesting strong selective pressure to maintain their function. However, the discovery of gBGC's influence on UCEs adds another layer of complexity to their evolutionary story. How gBGC Contributes to Ultraconserved Elements Counteracting Genetic Drift: In regions with high recombination rates, gBGC can effectively c
Post a Comment
Read more

Neo-Darwinism, Extended Evolutionary Synthesis, and the Question of God

Image
The relationship between science and religion, particularly in the context of evolution, has been a subject of ongoing debate. Neo-Darwinism, the prevailing evolutionary theory for much of the 20th century, often appeared to exclude the possibility of a divine creator. However, the Extended Evolutionary Synthesis (EES), a more recent development in evolutionary biology, offers a framework that some argue is more compatible with theistic belief. Let's explore the reasons behind these differing perspectives. Neo-Darwinism and the Exclusion of God Neo-Darwinism, also known as the Modern Synthesis, combined Darwin's theory of natural selection with Mendelian genetics. It emphasized the role of random mutations and natural selection as the primary drivers of evolutionary change. This mechanistic view of evolution led many to conclude that it left no room for divine intervention or purpose. Here are some key aspects of Neo-Darwinism that contributed to this perception: Ra
Post a Comment
Read more

UCEs challenges neo-Darwinism and calls for an extended evolutionary synthesis

Image
Ultraconserved elements (UCEs) are stretches of DNA that are virtually identical across a wide range of species, often remaining unchanged for hundreds of millions of years. Their extreme conservation suggests they play crucial roles in biological function, yet their precise functions remain largely mysterious. The existence and properties of UCEs challenge several tenets of neo-Darwinism and contribute to the call for an extended evolutionary synthesis (EES) in the following ways: Challenge to the concept of junk DNA: Neo-Darwinism traditionally viewed much of the genome as "junk DNA" with no significant function. The high level of conservation of UCEs suggests that these regions are functionally important, even if their specific roles are not yet fully understood. Questioning the neutrality of mutations: Neo-Darwinism emphasizes the role of random mutations and natural selection in driving evolution. The extreme conservation of UCEs suggests that mutations in
Post a Comment
Read more

The human microbiome reduces Genetic Entropy

Image
"When thinking about genetics, we often think of lineages and the passing down of genes through generations. We think about vertical transmission. However, bacteria also acquire genetic material through horizontal transmission. As Smillie et al. noted in a 2011 study in Nature: “The human body is a complex biological network comprising ten microbes for each human cell and 100 microbial genes for each unique human gene”. Understanding bacterial networks of gene exchange is thus essential for an understanding of ourselves.'- Swapping genes within and beyond our bodies.”  The human microbiome, a complex ecosystem of bacteria, fungi, viruses, and other microorganisms residing within and on our bodies, plays a crucial role in human health. Recent research has unveiled its potential to mitigate the negative impacts of our genetic load, the burden of potentially harmful mutations we carry in our DNA. This intricate interplay between our genes and our microbiome offers exc
Post a Comment
Read more

Ultraconserved Elements: A Challenge to Neo-Darwinism, Explained by the Extended Evolutionary Synthesis

Image
Ultraconserved elements (UCEs) are stretches of DNA that are nearly identical across a wide range of species, exhibiting extraordinary conservation across vast evolutionary distances. These sequences, often hundreds of base pairs long, remain unchanged for millions of years, defying the expected accumulation of mutations over time. The existence of UCEs poses a significant challenge to traditional neo-Darwinian evolutionary theory, prompting the need for alternative explanations. The Extended Evolutionary Synthesis (EES), a framework that builds upon and expands neo-Darwinism, offers a more comprehensive understanding of these enigmatic genomic features. Neo-Darwinism's Limitations in Explaining UCEs Neo-Darwinism, the prevailing evolutionary paradigm for much of the 20th century, emphasizes the gradual accumulation of random mutations and natural selection as the primary drivers of evolutionary change. While this framework has been remarkably successful in explaining m
Post a Comment
Read more

Evo-Devo's Contributions to the Extended Evolutionary Synthesis

Image
The Extended Evolutionary Synthesis (EES) is a developing field that challenges the traditional neo-Darwinian understanding of evolution. It incorporates new insights from various disciplines, including evolutionary developmental biology ("evo-devo"), to provide a more comprehensive view of how evolutionary change occurs. Evo-devo focuses on the interplay between development and evolution, examining how changes in developmental processes can lead to the emergence of new traits and drive evolutionary diversification. This article will explore the significant contributions of evo-devo to the EES, highlighting how it has reshaped our understanding of evolutionary processes. Challenging the Gene-Centric View Traditional neo-Darwinism places a strong emphasis on genes as the sole carriers of heritable information. Evo-devo challenges this gene-centric view by emphasizing the role of developmental processes in shaping phenotypic variation. It argues that evolution is n
Post a Comment
Read more