NeoDarwinian Review

We delve into the fascinating world of autopolyploidy, a phenomenon where an organism unintentionally undergoes a whole-genome duplication. This spontaneous doubling of chromosomes, unlike allopolyploidy (fusion of genomes from different species), arises from internal errors during cell division. The resulting polyploid individual boasts a significantly increased chromosome number compared to its diploid kin. Autopolyploidy presents a captivating paradox . On the surface, such a drastic alteration to the genetic blueprint appears detrimental. Traditionally, mutations are viewed as random changes, often deleterious , in the DNA sequence. However, autopolyploidy challenges this notion. By creating a polyploid state, the organism essentially gains a redundant copy of its entire genome. This redundancy can act as a buffer, potentially mitigating the effects of harmful mutations that might otherwise be lethal in a diploid organism. Intriguingly, autopolyploidy's impact ext...

Living organisms exhibit a remarkable ability to adapt to their environment. This phenomenon, known as phenotypic plasticity, allows individuals to express different phenotypes (observable traits) based on the conditions they encounter. While the underlying genetic code remains constant, the environment can influence how these genes are expressed, leading to a diverse range of phenotypes within a single genotype. This journal entry delves into the fascinating role of epigenetics in mediating phenotypic plasticity, providing a deeper understanding of how organisms fine-tune their traits in response to environmental cues. Deciphering the Dance: DNA vs. Epigenetics Traditionally , phenotypic variation has been attributed to alterations in the DNA sequence itself, through mechanisms like neo darwinian random mutations and gene shuffling during sexual reproduction. However, the advent of epigenetics has revolutionized our understanding of how organisms achieve phenotypic p...

The human brain, with its intricate folds and remarkable processing power, stands out amongst the animal kingdom. This evolutionary marvel, particularly the enlarged and folded cerebral cortex, is linked to our complex cognitive abilities. But how did our brains achieve this impressive size and complexity? Recent research delves into the fascinating world of epigenetics , revealing a key player: epi-regulation of the growth factor Epiregulin . The cerebral cortex, the outermost layer of the brain responsible for higher-order functions, boasts a significantly larger number of neurons and glial cells in humans compared to other mammals, particularly rodents like mice. Interestingly, the basic process of creating these cells, neurogenesis, is quite similar across mammals. The secret lies in how efficiently these progenitor cells multiply during fetal development. There are two main types of neural progenitor cells (NPCs) at play: apical progenitor cells (APCs) and basal proge...