This Islands Turn Animals Into Giant Monsters — Here's Why.

On one island in Indonesia, elephants shrank to about the size of a pony, rats grew as long as a house cat, and storks stood taller than the people living there. Those people were barely more than a metre tall. So why would the same island make some animals enormous and others tiny? This documentary is about the island rule, the pattern scientists have found on islands all over the planet: small animals tend to get bigger, and big animals tend to get smaller. Amelia follows it from the first studies to the biggest test of it yet, through the pressures that drive it, to the island where it may have shaped humans too. It starts in 1964, when J. Bristol Foster compared island mammals with their mainland relatives, and in 1973, when Leigh Van Valen gave the pattern its name. You'll see it in the St Kilda field mouse, in the dodo, and in the hippos, deer and elephants that shrank on Mediterranean islands. On Sicily and Malta, an adult male Palaeoloxodon falconeri stood about 96 centimetres at the shoulder, and skulls like its own may have helped inspire the Cyclops of Greek myth. On Jersey, cut off by rising seas, red deer shrank to an average of around 36 kilograms, in what researchers estimate was less than 6,000 years. Then the why: food, predators and competition, and the 2021 study that compared about 2,400 island populations and found the rule real and widespread in mammals, birds and reptiles. On Flores, the skeleton found at Liang Bua in 2003, Homo floresiensis, shared the island with dwarf Stegodon, giant rats and a stork nearly 1.8 metres tall. Then the twist: fossils from eastern Australia, and the 2009 paper by Scott Hocknull and his colleagues, suggest the Komodo dragon most likely evolved its giant size in Australia and arrived big. And finally the dark side: what islands do to the animals they make, from Jersey's dwarf deer to the dodo, and why the Komodo dragon was moved to Endangered in 2021. What you'll take away: • Why islands push small animals to grow and big animals to shrink • How a Sicilian elephant ended up standing at about waist height, and why its skull may have fed the Cyclops legend • How fast island dwarfing can happen, from Jersey's red deer • The three pressures behind the island rule: food, predators and competition • What the 2021 test of about 2,400 island populations found, from isolation to climate • Who the hobbits of Flores were, and the dwarf and giant animals they lived with • Why the Komodo dragon may not be an island-made giant at all Where the science is settled, we say so. Where researchers still disagree, we tell you that too. So why do islands rewrite the rules of size? Tell us in the comments which island giant or dwarf surprised you most. SOURCES Every study, article and image credit behind this video, with links: https://docs.google.com/document/d/1X... Music: Epidemic Sound · Voice: ElevenLabs #IslandRule #IslandGigantism #KomodoDragon #Evolution #NatureDocumentary