How have humans directly observed evolution?

Humans have directly observed evolution through various means, such as studying microbial populations in laboratories, where rapid genetic changes can be tracked over generations. The evolution of antibiotic resistance in bacteria is a clear example, demonstrating how these organisms adapt quickly to environmental pressures. Additionally, researchers have documented observable changes in species, such as the beak sizes of finches in the Galápagos Islands, which shift in response to food availability. These instances highlight the dynamic nature of evolution in real-time.