Are The World's Smallest And Largest Lizards Both Victims of Island Dwarfism?
Last week, a team of German scientists announced the discovery of four new species of miniature reptiles. Found on the island of Madagascar, the lizards, which varied in length from 29 millimeters to just over an inch, are the tiniest ones found yet. Prior to this the honor belonged to dwarf gecko Sphaerodactylus ariasae which, at a total length of 1.3 inches now appears to be almost gigantic in comparison.
The smallest of the four, the Brookesia Micra, which was found on the islet of Nosy Hara is so miniature that the young ones can fits on the head of a matchstick. As you can imagine, locating the lizards was no easy task. Not only are they tiny, but they are also difficult to spot in the daytime, which they spend hidden inside leaf litter. The team of researchers led by Dr. Glaw had to therefore scour the forests of Madagascar during the night, when the tiny reptiles scamper out in search of food.
Scientists believe the Brookesia Micra represents a rather extreme case of island dwarfism - A process that involves the reduction in size of larger animals, when they are restricted to living in small environments such as the one it was found in. Experts believe it is their way of adapting in an environment where food periodically declines to a borderline level. Being tinier means they need fewer resources and smaller spaces to live in, allowing them to survive.
While the Brookesia Micra is obviously a dwarf, some experts believe so is the Komodo dragon, the largest lizard to currently inhabit the world. Found only on Indonesia's Komodo and Flores Islands, these ferocious monsters that can grow up to 10 feet long and weigh as much as 330 pounds are strong enough to drag down and devour animals like deer and even, water buffalos. Though that is huge by our current standards, it was not so during the Pleistocene Era, when the Komodo had to compete with an even heftier monster - A giant lizard that weighed 23-feet long and weighed a whopping 1,370 pounds!
Other experts disagree with this theory, believing instead that the large lizard is a classic example Island Gigantism - That is the Komodo dragon kept growing in size because it was the only carnivorous animal on the island and hence, never had to compete for food.
While this will always be up for debate, the fact that both the world's tiniest and biggest lizards are in danger of disappearing completely is something nobody argues about. We sure hope scientists are able to preserve their environment and prevent that from happening.
sources: Discovery.com, Pbs.org,Wikipedia.com