Modern Synthesis Review

The article "Epigenetics and the Evolution of Darwin's Finches" by Michael K. Skinner challenges neo-Darwinism by proposing that epigenetic changes, in addition to genetic mutations, can play a significant role in evolution. Neo-Darwinism is the prevailing theory of evolution, which holds that evolution is driven by natural selection acting on genetic mutations. Skinner argues that epigenetic changes can accumulate over generations to produce new species without natural selection on mutations. Skinner supports his argument with evidence from studies of Darwin's finches. Darwin's finches are a group of closely related birds that live on the Galapagos Islands. The finches have evolved into a wide variety of species, each with a different beak shape that is adapted to a particular food source. Skinner's studies have shown that the epigenetic changes that control beak shape can be inherited from parents to offspring. This suggests that epigenetic chan...

The article "The Illusions of the Modern Synthesis" by Denis Noble argues that the Modern Synthesis, the dominant theory of evolution in the 20th century, is based on four misinterpretations of what molecular biology had shown. These misinterpretations, which Noble calls "illusions," are: Natural selection. The Modern Synthesis assumes that natural selection is the only important force driving evolution. However, Noble argues that molecular biology has shown that other forces, such as epigenetics and developmental plasticity, can also play a significant role. The Weismann barrier. The Modern Synthesis also assumes that there is a barrier between the germ line (the cells that give rise to gametes) and the soma (the cells that make up the body). This barrier is thought to prevent the inheritance of acquired characteristics, such as changes that occur in the body due to environmental factors. However, Noble argues that molecular biology has shown that the ...

The phrase "sins of the fathers," most notably articulated in the biblical Ten Commandments, has resonated through millennia, often interpreted as a declaration of divine justice or inescapable familial curses. Exodus 20:5 states that God “visits the iniquity of the fathers on the children to the third and the fourth generation of those who hate me." Its significant epigenetics involves three to four generations of inheritance. While traditionally viewed through theological or purely social lenses, the burgeoning field of epigenetics offers a startlingly resonant biological perspective. It suggests that the experiences, environments, and behaviors metaphorically, the "sins" or perhaps more neutrally, the significant life events of one generation can indeed leave tangible, inheritable marks on the biological functioning of their descendants, challenging long-held assumptions within evolutionary biology. The biblical concept, particularly within the c...

"As buds give rise by growth to fresh buds, and these, if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications." - Darwin's tree of Life The article "The Tree of One Percent" by Tal Dagan and William Martin discusses the limitations of the tree of life model for understanding microbial evolution. The tree of life is a branching diagram that depicts the evolutionary relationships between all living things. It is based on the assumption that all life evolved from a common ancestor through a series of bifurcations, or lineage splittings. However, lateral (Horizontal) gene transfer (LGT aka HGT) is a common process in microbial evolution. LGT is the horizontal transfer of genes between unrelated organisms. It can occur through a...

The journal article "Epigenetics, paleontology, and evolution" delves into a fascinating and increasingly critical intersection of disciplines, challenging established paradigms in evolutionary biology. It explores how epigenetics, the study of heritable changes in gene expression that do not involve alterations to the underlying DNA sequence, provides a powerful lens through which to re-examine the fossil record and the very mechanisms driving evolutionary change. This confluence of fields suggests a more nuanced and dynamic understanding of life's history, moving beyond the strictures of the Modern Synthesis. At its core, the article highlights the profound involvement of epigenetics in shaping biological diversity and evolutionary trajectories. Traditionally, evolution has been viewed primarily through the lens of genetic mutations and natural selection acting upon them. However, epigenetic modifications – such as DNA methylation, histone modification, and...

In the ever-evolving landscape of genetics, the article "The mechanisms of epigenetic inheritance: how diverse are they?" by Adrian Bird presents a compelling exploration into the multifaceted world of epigenetics and its profound implications for our understanding of heredity. Far from being a niche area of study, epigenetics is revealed as a central player in determining how genetic information is expressed and, crucially, how these expression patterns can be passed down through generations without alterations to the underlying DNA sequence itself. This challenges the long-held tenets of the Modern Synthesis of evolution, suggesting a more dynamic and intricate picture of inheritance than previously conceived. At its core, epigenetics encompasses heritable changes in gene function that occur without a change in the DNA nucleotide sequence.  Bird's article meticulously details the diverse mechanisms through which these epigenetic marks are established, maint...