The scientific principle that explains buoyancy is Archimedes' principle. This principle states that an object submerged in a fluid experiences an upward force equal to the weight of the fluid it displaces. Buoyancy is fundamental in various fields, including physics, engineering, and biology, explaining phenomena like why ships float and how aquatic organisms adapt to their environments. Understanding buoyancy is essential for designing vessels, studying fluid dynamics, and comprehending animal adaptations in aquatic ecosystems.