Insular Dwarfism: 12 Species that Evolved to be Small
Island life isn’t all sandy beaches and coconuts. Sometimes, it’s rough, with very little food or freshwater available, and if you can’t get off the island, you’d better adapt. That’s exactly what these 12 miniature species did over thousands of years due to scarcity of resources, eventually becoming smaller versions of their mainland relatives. They’re not all insanely adorable tiny animals that melt us into big piles of fawning goo, but they are fascinating, rare, and all too often endangered or extinct.
Little People of Flores
(images via: wikipedia, science daily)
Could a tiny sub-species of in the genus Homo have co-existed in Indonesia with humans as recent as 12,000 years ago? First dubbed a “hobbit-like human ancestor”, it was soon discovered that Homo floresiensis was in fact its own species, standing just three feet tall, about the height of a modern human toddler. Nine skeletons were found in Flores, Indonesia in 2003 and have been studied extensively since then, with some scientists still arguing that they are actually deformed Homo sapiens. The team that discovered H. floresiensis believe the species is an example of insular dwarfism, with their growth restricted by a limited choice of food on the island.
Pygmy Three-Toed Sloth
(image via: bbc news)
When it comes to sloths, opinions tend to be radically divided: some people think they’re adorable, while others find them absolutely terrifying. But the critically endangered pygmy three-toed sloth, found only on the tiny island of Isla Escudo de Veraguas near Panama, is a miniature version of its mainland relatives, and is especially cute when swimming – it almost looks like a fuzzy turtle!
Channel Islands Pygmy Mammoth
(image via: wikipedia)
When you hear the word “mammoth”, you think of something epically huge. Not that the Channel Islands Pygmy Mammoth was a dainty little creature at 2,000 pounds, but it would still have been easily dwarfed by its 20,000-pound ancestor, the Columbian Mammoth. Remains of this species, which evolved to fit within the ecosystem of the now mostly-submerged Santa Rosae island off the coast of California, were first discovered in 1856.
(images via: wikipedia)
Unlike today’s pygmy elephants, which are subspecies of their own, prehistoric dwarf elephants evolved to be much smaller than modern elephants due to their insularity on islands around the world including Crete, Cyprus, Timor and the same island of Flores, Indonesia where pygmy human relatives were found. And unlike prehistoric dwarf mammoths, dwarf elephants really were small: the Cyprus dwarf elephant likely weighed around 440 pounds.
Channel Islands Fox
(image via: just chaos)
Aww, isn’t that a cute little kitten… oh… wait. It’s not a kitten at all. The Channel Islands Fox first evolved from the Gray Fox when they “rafted” over to the islands off the coast of California over 10,000 years ago and were faced with limited resources. They’re easy prey for eagles, being smaller than domestic house cats, and also highly susceptible to parasites and diseases brought over from the mainland.
(image via: soham pablo)
Pygmy hippos are about the same size as pigs – though technically, hippos are more closely related to whales and dolphins than to any of their fellow land animals. Semi-aquatic vegetarians, these miniature mammals are difficult to study because they’re nocturnal and very shy. Only about 3,000 remain in the wild, mostly in Liberia.
(image via: wikipedia)
The Bali Tiger may have been more comparable in size to leopards than to other tiger subspecies, but they were no less fierce. Sadly, these animals disappeared by the middle of the 20th century, though scientists believe there were never very many of them in the first place. These dwarf tigers were found exclusively on the island of Bali where they were hunted to extinction due to perceived threats and also the desire for jewelry made from their teeth and claws.
Cozumel Island Raccoon
(image via: animalesextincion.es)
Weighing just about 8-9 pounds, Cozumel Island racoons look exactly like their mainland relatives except for their diminutive size, the black bands on their throats and their golden yellow tails. They live on Cozumel Island off the coast of the Yucutan Peninsula in Mexico, and less than 300 remain. The Dwarf Coati, a relative of the raccoon, and a species of dwarf gray fox are also found on the island.
Balearic Island Cave Goat
(image via: mongabay)
The extinct Balearic Island Cave Goat wasn’t just a shorty at only 19.5” tall – its isolation on the rocky, nutrient-poor islands in the Mediterranean caused it to develop some even more unusual characteristics. Like crocodiles, this goat was able to grow at flexible rates, halting the growth process when food was unavailable. As far as scientists know, this goat was the only mammal ever to adapt in this way, and it probably helped the goat survive for five million years before being driven into extinction by human hunters.
Mindoro Dwarf Buffalo
(image via: edmond valerio)
There are so few Mindoro Dwarf Buffalo left, it’s rare for anyone to spot more than a solitary individual. Originally found all over the island of Mindoro in the Philippines, its range has been dramatically reduced by human civilization, hunting and logging. In fact, sightings of this mini water buffalo are so unusual that scientists know very little about its ecology. After being declared a critically endangered species, the Mindoro buffalo population has experienced a slight but very encouraging uptick.
Bernissartia – Tiny Crocodiles
(image via: wikimedia commons)
Imagine a cute “baby” crocodile that never grows up. That’s basically what Bernissartia, a prehistoric reptile from the Early Cretacious period around 130 million years ago, would seem like to us. Smaller than a house cat, Bernissartia looked just like modern-day crocodiles but had jaws more suited to catching fish than dragging a full-grown man underwater. It would have stood at sharp contrast to the nightmarishly enormous crocs of the day, like Sarcosuchus.
(image via: wikimedia commons)
Key Deer may not be around too much longer. Native only to the Florida Keys, this offshoot of white-tailed deer tops out at about 75 pounds and the antlers of males bear a signature white, velvety coating. Because of human encroachment, their habitat has been shrunken to a handful of lesser populated keys, and they swim from one island to another in search of fresh water.