So, look at the title and you can see that this has something to do with islands. So, what is this strange phenomenon?
Island syndrome is a very rare occurence in which animals are stuck on islands and evolve into much smaller or larger forms in order to maintain balance. This phenomenon has happened many times but mostly in Europe, twice in the Late Cretaceous period and in the Miocene, when Europe was a bunch of islands. It also happened in Indonesia and the Phillippines in the Late Pleistocene.
The first major occurence of this was in the heyday of the dinosaurs, 86 mya, in what is now Romania and Hungary. These lands were small islands back then, and dinosaurs such as Balaur and Zalmoxes were very small compared to their relatives. Magyarosaurus was the smallest sauropod ever, but the reverse happened with the dinosaur cousins, the pterosaurs. Hatzegopteryx was one of the biggest pterosaurs, and one of the bulkiest. It was so heavy that when its arm was discovered, it was thought to be the femur of a large theropod such as T-rex.
Then after the extinction of the dinosaurs, Europe was once again home for the reverse of this strange phenomenon to happen in the Miocene Epoch. In what is now Gargano, Italy, there were huge hedgehogs, small deer, gigantic rats, and other rodents of similarly huge sizes. There were also eagle-sized falcons and giant flightless geese. This was around 8 mya.
Then, much more recently, at just 400,000 years ago, island syndrome came around in Flores, Indonesia. Homo erectus, one of our more recent ancestors, had migrated out of Africa and into Eurasia and had reached the Malayan-Indonesian archipelago. Flores is a tiny island, and the early humans there became much more smaller versions of their mainland counterparts, called Homo floresiensis. Homo floresiensis was around 3 feet tall and a bit more stocky than us, so paleontologists affectionately call them “hobbits” after the fictional race of The Lord of the Rings. Sadly, the real-life hobbits died out at the least 80,000 years ago as far as we know, just before modern humans arrived on the scene.
So, that’s island dwarfism for you!
Anay Ganesh 