Have you ever wondered why some animals living on islands are much bigger or smaller than their mainland relatives? In this episode on Earth SciShow, MrEarthGuy explores the phenomena of insular gigantism and insular dwarfism, which occur when animals evolve different body sizes on islands due to different ecological pressures. We also discuss how these phenomena help support the evidence for evolution and why they matter for conservation. Join us as we discover the amazing diversity and adaptation of life on Earth