Month: September 2022

NEW PARADIGM IN DEVELOPMENTAL BIOLOGY. "Evolutionary developmental biology (evodevo) attempts to explain how the process of organismal development evolves, utilizing a comparative approach to investigate changes in developmental pathways and processes that occur during the evolution of a given lineage." https://lnkd.in/dD4GcAS View in LinkedIn

ONE ASPECT OF THE PICTURE. "Evolutionary genetics uses a population approach to understand how organismal changes in form or function are linked to underlying genetics, focusing on changes in gene and genotype frequencies within populations and the fixation of genotypic variation into traits that define species or evoke speciation events." https://lnkd.in/dD4GcAS View in LinkedIn

ANOTHER PART OF THE PICTURE. "Microevolutionary processes, including mutation, genetic drift, natural selection and gene flow, can provide the foundation for macroevolutionary patterns observed as morphological evolution and adaptation." https://lnkd.in/dD4GcAS View in LinkedIn

LINKING THE PARTS. "The temporal element linking microevolutionary processes to macroevolutionary patterns is development: an organism's genotype is converted to phenotype by ontogenetic processes. Because selection acts upon the phenotype, the connection between evolutionary genetics and developmental evolution becomes essential to understanding adaptive evolution in organismal form and function." https://lnkd.in/dD4GcAS View in LinkedIn

GENE PATHWAYS VERSUS POPULATIONS. "For decades, developmental geneticists have been elucidating the genes and genetic pathways involved in floral development in model species in laboratory environments. Simultaneously, evolutionary biologists have investigated genetic variation in natural populations as a means of understanding the genetic architecture underlying the development and evolution of adaptive (= heritable beneficial phenotype) traits." https://lnkd.in/dD4GcAS View in LinkedIn

FINAL CONSIDERATION. "Our next step is to determine which naturally occurring genetic changes affect ecologically relevant phenotypes and how natural selection acts upon those phenotypes to confer adaptive evolution." https://lnkd.in/dD4GcAS View in LinkedIn

POTENTIAL RED HERRINGS. "While the underlying genetic networks are often conserved across plant lineages, genes identified to be important in the regulation of phenotypic changes for wildtype and mutant plants in model species may not translate into the types of genetic and phenotypic changes that are selected upon and affect survival and reproductive fitness under natural environmental conditions." https://lnkd.in/dD4GcAS View in LinkedIn

TEMPORAL AND SPATIAL CONSIDERATIONS. "Rampant polyploidy in natural populations results in duplicate gene copies that can undergo differential selection and allow for temporal and positional alternations in genetic networks to emerge, conferring novel phenotypes upon which selection may act." https://lnkd.in/dD4GcAS View in LinkedIn

CANDIDATE GENES APPROACH. "Large numbers of comparative studies have demonstrated that changes in expression patterns of developmental genes are correlated with the evolution of morphological phenotypes. These data underlie the ‘candidate gene’ approach, in which genes that are functionally determined to cause particular phenotypes when mutated are hypothesized to be responsible for similar phenotypic changes during evolution." https://lnkd.in/dD4GcAS View in LinkedIn

ASSUMPTIONS WITH CANDIDATE GENES. "This approach requires two assumptions: one is that genes and gene regulatory networks (GRNs) responsible for developmental processes are conserved over large evolutionary distances. The second is that changes in the regulation of these genes, resulting in altered temporal and spatial expression patterns, affect the phenotype and thus are responsible for fixed differences in organismal morphology. For many studied developmental processes, these two assumptions appear to hold true." https://lnkd.in/dD4GcAS View in LinkedIn