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Showing posts from July, 2023

Epigenetics explains Lactose Intolerance without Darwin

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The article "Lactase nonpersistence is directed by DNA-variation-dependent epigenetic aging" by Labrie et al. (2016) investigated the epigenetic factors that contribute to lactase nonpersistence. Lactase nonpersistence is the inability to digest lactose, a sugar found in milk. This is a common trait in adult mammals, except in certain human populations that exhibit lactase persistence. The researchers found that epigenetic changes, which are chemical modifications to DNA that can affect gene expression, play a role in lactase nonpersistence. Specifically, they found that the LCT gene, which encodes the lactase enzyme, accumulates certain types of epigenetic marks with age in lactase nonpersistent individuals. These marks silence the gene, leading to a decrease in lactase production. The researchers also found that the DNA sequence of the LCT gene can influence the rate of epigenetic aging. Individuals with a certain DNA variation at the LCT gene are more likely t...

Epigenetics explains metamorphosis without Darwin

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The lay article "Why Insect Memories May Not Survive Metamorphosis" by Yasemin Saplakoglu discusses the recent findings of a study that suggests that memories formed by fruit fly larvae do not persist in adults. The study, which was published in the journal Nature , found that the brains of fruit flies undergo a dramatic reorganization during metamorphosis, with many neurons being destroyed and new ones being formed. This reorganization appears to erase any memories that were formed in the larval stage. The study's findings have implications for our understanding of how memory works in general. It has long been thought that memories are stored in the brain in a physical form, such as the connections between neurons. However, the findings of this study suggest that memories may also be stored in an epigenetic form, meaning that they are influenced by changes in gene expression. Epigenetic changes are changes in gene expression that are not caused by changes in...

Evidence of Moses

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The documentary "Patterns of Evidence: Exodus" presents a number of pieces of evidence that it claims support the existence of Moses and the Exodus story. These include: The Merneptah Stele, an Egyptian victory stele that mentions a people called "Israel" living in Canaan. This is the earliest known extra-biblical reference to Israel, and it is dated to the 13th century BC, which is the same time period that the Exodus is thought to have occurred. The Hyksos, a group of Semitic people who ruled Egypt from the 17th to the 15th centuries BC. Scholars believe that the Israelites were originally part of the Hyksos, and that they were enslaved by the Egyptians when the Hyksos were expelled from Egypt. The Biblical account of the Exodus includes a number of details that are consistent with what we know about ancient Egypt, such as the use of chariots, the construction of pyramids, and the practice of child sacrifice. Ultimately, the question of whether or not ...

Epigenetics and the EES explains macro evolution better than NeoDarwinism

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Epigenetic changes and the Extended Evolutionary Synthesis (EES) are two relatively new theories that have the potential to explain macroevolution better than Neo-Darwinism. Neo-Darwinism is the prevailing theory of evolution, which states that evolution occurs through the process of natural selection, acting on genetic variation. However, Neo-Darwinism has difficulty explaining some aspects of macroevolution, such as the evolution of new traits and the rapid diversification of species. Epigenetic changes are changes in gene expression that are not caused by changes in the DNA sequence. These changes can be inherited, and they can have a significant impact on the phenotype of an organism. For example, epigenetic changes have been linked to the development of cancer, as well as to the effects of environmental factors on gene expression. The EES is a newer theory that incorporates epigenetic changes outside of the traditional Neo-Darwinian model. The EES proposes that epigene...

Further illusions: On key evolutionary mechanisms that could never fit with Modern Synthesis

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The article "Further illusions: On key evolutionary mechanisms that could never fit with Modern Synthesis" by Radomir Crkvenjakov and Henry H Heng critically examines the Modern Synthesis (MS) of evolution, which is the prevailing theory of evolution in the biological sciences. The authors argue that the MS is based on a number of false assumptions, including the following: That the gradual accumulation of gene mutations within microevolution leads to macroevolution. That present evolutionary events can be linearly extrapolated to the past to reconstruct Life's history. That stasis, as the most prominent pattern of the deep history of Life, is a puzzle to the MS. The authors argue that these assumptions are false because they ignore the role of system information in evolution. They argue that system information is maintained by species-specific karyotype code, and that macroevolution is based on the whole genome information package rather than on specific gen...

The Illusions of the Modern Synthesis

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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 ...

How microbes ‘jeopardize’ the modern synthesis"

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The article "What is mutation? A chapter in the series: How microbes ‘jeopardize’ the modern synthesis" by Susan M. Rosenberg discusses the role of mutation in evolution and how our understanding of mutation has changed in recent years. Traditionally, mutations were thought to be random events that occurred with no regard to the environment. However, recent research has shown that mutations can be regulated by environmental factors, such as stress. For example, some bacteria can increase their mutation rate when they are exposed to toxins or other harmful substances. This suggests that mutations may not be as random as previously thought, and that they may play a more active role in evolution. The article also discusses the non-random nature of mutations. Mutations do not occur evenly throughout the genome, but instead tend to cluster in certain regions. This suggests that mutations may be more likely to occur in genes that are important for adaptation. The findi...

Epigenetics sees the Organism as "Agent" not a slave to DNA per Darwin

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The article "The agential perspective: Countermapping the modern synthesis" by Denis M. Walsh and Gregory Rupik (2023) compares and contrasts two theoretical perspectives on adaptive evolution: the orthodox Modern Synthesis perspective and the nascent Agential Perspective. The Modern Synthesis perspective is the dominant view of evolution in biology. It is based on the idea that evolution is driven by natural selection, which is the process by which individuals with advantageous traits are more likely to survive and reproduce than individuals with less advantageous traits.  The Agential Perspective is a newer view of evolution that emphasizes the role of agency in shaping the course of evolution. Agency is the ability of an individual to make choices and act on those choices. In the context of evolution, agency refers to the ability of individuals to make choices that affect their own fitness and the fitness of their offspring. The Agential Perspective argues tha...