: Organisms with traits better suited to their environment are more likely to survive and reproduce, passing those advantageous genes to their offspring.
Scientists distinguish between two scales of evolutionary change: Evolutionary mechanisms part 1: What is evolution? 1. Evolution
: Random chance events (like a natural disaster) can abruptly change which traits are passed down by removing certain individuals from the population. : Organisms with traits better suited to their
: Random changes in genetic material create new variations. While many mutations are neutral or harmful, some provide benefits that natural selection can then act upon. 1. Evolution
: The movement of genes between different populations through migration and interbreeding. Scale and Patterns
Evolution is driven by four primary mechanisms that alter the genetic makeup of populations: