Evolution Blog

This demonstrates genetic drift by contrasting two populations of fish on separate islands. On Island A, the large population maintains its genetic diversity, demonstrating that genetic drift has little effect in stable, large populations. However, Island B shows a dramatic change in population color due to random chance events affecting a small group, leading to the loss of diversity. This picture emphasizes that genetic drift is a random process that significantly impacts smaller populations, leading to reduced genetic variation, while it has minimal effects on larger populations. Additionally, it highlights that genetic drift is not the same as natural selection, which involves differential survival based on advantageous traits rather than random events.

Plasticity is the ability of an organism to change its phenotype in response to environmental conditions. This enhances survival and reproductive success.There are two types, developmental plasticity, which occurs during an organism's development, and phenotypic plasticity, which manifests throughout its life. To determine if a trait is plastic, you would first identify the specific trait to study, such as leaf size in a particular plant species. Then select contrasting environmental conditions, such as full sunlight versus shaded areas, and conduct a controlled experiment with identical plants grown under both conditions. Throughout the experiment, regularly measure the trait of interest and utilize photographs or diagrams to visualize growth changes over time. Statistical analyses would help compare the means of the trait between the environments, looking for significant differences that indicate plasticity. Also assessing the genetic background of the organisms can confirm that ...

     Natural selection operates on phenotypes which are the observable traits of organisms. Because these traits determine how well individuals interact with their environment, they ultimately affect their survival and reproductive success. While it’s true that genotypes, the genetic blueprints, are what get passed to the next generation, the relationship between genotype and phenotype is important. Genotypes provide the potential for traits to exist, but environmental factors and developmental processes shape how these traits manifest. For example, in a population of rabbits, variations in speed can be linked to genetic differences, but it’s the faster individuals that are more likely to escape predators and reproduce. This differential survival leads to a higher frequency of advantageous alleles in the population over generations. As phenotypes that enhance survival and reproduction become more common, the underlying genotypes associated with those traits also increase ...