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Challenging the Modern Synthesis' Gene-Centered View

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The article by Jablonka and Lamb critiques the Modern Synthesis , a dominant 20th-century theory in evolutionary biology that merged Darwinian evolution with Mendelian genetics. The Modern Synthesis placed genes at the center stage, crediting them as the sole carriers of heritable traits. Jablonka and Lamb argue that this gene-centered view overlooks the influence of other inheritance systems on evolution. Introducing Alternative Inheritance Systems The authors delve into various inheritance systems beyond genes, including: Epigenetics: This refers to modifications on genes that affect gene expression without altering the DNA sequence itself. These modifications can be passed down to offspring, influencing their traits. For instance, maternal nutrition can epigenetically influence offspring development. Behavioral Inheritance: Learned behaviors can be socially transmitted across generations, impacting the survival and reproduction of organisms. An example is birds inhe

The Incommensurable Frameworks of the Modern Synthesis and the Extended Evolutionary Synthesis

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Incommensurable refers to things that cannot be compared using the same standards or metrics. Incommensurable ideas or theories stem from fundamentally different frameworks, making direct comparison challenging. The Modern Synthesis (MS) and the Extended Evolutionary Synthesis (EES) are two frameworks for understanding evolution. While the MS laid the foundation for evolutionary biology, the EES proposes significant revisions to incorporate new discoveries. Here are 10 ways they differ: Units of Selection: The MS focuses on genes as the primary unit of selection, while the EES acknowledges the role of higher-level units like organisms, groups, and even ecosystems. Origin of Variation: The MS emphasizes random mutations as the source of variation, while the EES recognizes the role of developmental processes and environmental cues in shaping variation. Nature of Phenotypic Change: The MS assumes phenotypic changes arise from genetic mutations, while the EES considers the p