Charles Darwin and the Discovery of Natural Selection
Charles Darwin made the groundbreaking discovery of natural selection. He observed that organisms with favorable traits are more likely to survive and reproduce, passing on those traits to future generations.
Artificial Selection: Shaping Outcomes through Human Intervention
Artificial selection involves deliberately pairing two organisms to produce desired traits in their offspring.
Gene Flow: The Transfer of Genes between Populations
Gene flow occurs when genes are transferred from one population to another through migration and mating.
Genetic Drift: Changes in Gene Frequency within a Population
Genetic drift refers to the random change in the frequency of a gene within a population. Over time, one gene may become more common, potentially replacing another.
Mutation: Altering Gene Structure for Future Generations
Mutation involves changes in the structure of a gene, such as duplications or deletions. These alterations can be passed on to subsequent generations.
The Four Components of Natural Selection
- Variation: Differences in traits among individuals within a population.
- Selection: Favoring traits that increase an organism's chances of survival and reproduction.
- Reproduction of Adaptation: Passing on advantageous traits to offspring.
- Overproduction: Producing more offspring than the environment can support.
Understanding Organisms through Homologous and Analogous Structures
Homologous structures are organs or skeletal elements that are similar among different organisms, indicating a common ancestry.
Analogous structures, on the other hand, are structures in different organisms that serve similar functions, but do not share a common ancestry.
Evidence of Evolution: Uniting Modern and Extinct Species
Various forms of evidence support the theory of evolution:
- Structural Similarities: Similarities in the physical structure of organisms.
- DNA: Shared genetic material between species.
- Fossils: Preserved remains of ancient organisms.
- Developmental Patterns: Similarities in the embryonic development of different species.