Move to the EES

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...

The Extended Evolutionary Synthesis (EES) represents a growing body of work that challenges the limitations of the traditional neo-Darwinian framework. It seeks to incorporate a wider range of biological phenomena and theoretical perspectives into evolutionary theory, leading to a more nuanced and comprehensive understanding of life's diversity and complexity. This essay explores the key themes of the EES, focusing on formalizations and expansions that enrich our understanding of evolution. Beyond the Gene-Centric View One of the central tenets of the EES is a move away from the gene-centric view of evolution. While genes undoubtedly play a crucial role in heredity, the EES emphasizes the importance of other factors, including: Developmental plasticity: Organisms are not simply passive recipients of genetic information; they actively respond to their environment, leading to phenotypic variations that can influence evolutionary trajectories. Niche construction: Organi...

For decades, biologists operated under a " gene-centric " view of inheritance and development. This perspective, dominant throughout much of the 20th century, held that individual genes acted as the primary determinants of specific traits or phenotypes. It was a simplified model, often encapsulated in the phrase " one gene, one phenotype ." This idea suggested a direct and linear relationship between a single gene and a corresponding trait, like a blueprint where each gene coded for a particular characteristic. This gene-centric view was rooted in the groundbreaking work of Gregor Mendel, who demonstrated the inheritance of discrete traits in pea plants. Mendel's laws of inheritance provided a fundamental understanding of how genes are passed from one generation to the next, but the complexity of gene expression and interaction was not fully appreciated at the time. The "one gene, one phenotype" concept was appealing in its simplicity and ...

Article by Danchin. The Modern Synthesis (MS) is the prevailing theory of evolution in biology. It was developed in the early 20th century by a group of scientists who integrated Darwin's theory of natural selection with the new science of genetics. The MS holds that evolution is driven by the differential reproduction of genes that confer a fitness advantage in a particular environment. In recent years, however, there has been growing dissatisfaction with the MS. This is because the MS does not adequately account for the role of non-genetic factors in evolution, such as epigenetics, developmental plasticity, and culture. Epigenetics is the study of changes in gene expression that are not caused by changes in the DNA sequence. These changes can be inherited from one generation to the next, and they can have a significant impact on the phenotype (observable characteristics) of an organism. Developmental plasticity is the ability of an organism to change its phenotype i...

"In a world dominated by HGT, gene duplication, gene loss, and such momentous events as endosymbiosis, the idea of evolution being driven primarily by infinitesimal heritable changes in the Darwinian tradition has become untenable." - KOONIN The Eugene Koonin, a highly respected evolutionary biologist, challenges the traditional Darwinian view of evolution as a gradual process driven by infinitesimal heritable changes. Koonin argues that the concept of gradualism is "untenable." This perspective reflects a growing recognition within the scientific community that evolution is a much more dynamic and complex process than previously thought. Challenging the Gradualist Paradigm Darwin's theory of evolution by natural selection revolutionized our understanding of the living world. It proposed that species evolve through the gradual accumulation of small, beneficial changes over vast periods. This gradualist view dominated evolutionary biology for over a c...

The traditional view of evolution, often called the Modern Synthesis, focuses primarily on random mutations and natural selection as the driving forces of change. While this framework has been successful in explaining aspects of life's diversity, it has also shown limitations in accounting for certain phenomena. The Extended Evolutionary Synthesis (EES) offers a broader perspective, incorporating additional mechanisms and factors that contribute to evolutionary change. Here's a look at how the EES moves beyond the traditional model: 1. Inclusive Inheritance: The EES challenges the gene-centric view of inheritance by recognizing that inheritance extends beyond DNA sequences. It acknowledges the role of epigenetic modifications, parental effects, ecological legacies, and cultural transmission in shaping traits and evolutionary trajectories. For instance: Epigenetics: Chemical modifications to DNA or associated proteins can alter gene expression patterns and be passe...