With their large size, venomous bite and the fantastical connotations of their name, Komodo dragons seem like a legend.
Now that status has been elevated further: scientists have discovered that their teeth are coated with a layer of iron that helps keep their serrated edges razor sharp.
It’s the first time such a coat has been seen in any animal, and one the researchers describe as “a striking and previously overlooked predatory adaptation in the Komodo dragon”.
The coating was discovered when researchers noticed that the tips and serrated edges of Komodo dragons’ teeth were covered in a layer of orange pigment. Upon closer examination, it was found that the enamel contained concentrated iron that made the teeth extra hard and resistant to wear, helping the dragons tear apart their prey.
Komodo dragons are the largest living reptiles, growing to over three meters in length and averaging 80kg in weight. They are native to several Indonesian islands, where they eat almost any prey, ranging from small birds to water buffalo and other Komodo dragons.
People were also killed by the lizards. In 2007 a child died on Komodo Island after being attacked by one of the animals. Two years later, a fruit picker on the island was killed by two of the animals after falling from a tree. In 2010, another Indonesian worker had a narrow escape Slaying a Komodo Dragon and be freed from his jaws.
Indonesian authorities consider banning tourists to the island amid concerns that visitors are affecting the animals’ mating habits and causing them to become friendly due to food handouts. The species is threatened with extinction due to habitat destruction and illegal hunting, with only an estimated 3,500 left in the wild.
In the latest study, a team led by researchers at King’s College London used advanced imaging, along with chemical and mechanical analytical techniques, to study teeth taken from several Komodo dragon specimens as well as numerous other living and extinct reptiles, including monitor lizards, crocodiles, alligators and dinosaurs.
The iron coating was most evident on the Komodo dragon teeth, but similar iron-rich coatings have been seen on the teeth of other reptiles. “It looks like this could be a very overlooked but widespread feature of reptilian teeth,” said Aaron LeBlanc, a lecturer in dental biosciences at King’s College and lead author of the study.
Komodo dragons’ curved, serrated teeth are similar to those of carnivorous dinosaurs, such as Tyrannosaurus rex. In the study, published in Nature Ecology & EvolutionLaBlanc and his team aimed to use the similarity to learn more about how dinosaur teeth may have been used when they were alive.
Although they identified a reinforced iron coating on many of the living reptiles’ teeth, they could not find evidence of it in any of the dinosaur fossils. Iron coatings could still have been present in carnivorous dinosaurs, the researchers believe. The iron may simply have been lost over time, as suggested by the fact that it could not be found on the fossilized teeth of reptiles closely related to Komodo dragons.
Owen Addison, a professor of oral rehabilitation at King’s College and the senior author of the study, said the discovery could eventually lead to new dental techniques that could be used in humans. “We think there is an opportunity to use the structure discovered in this work to inform new strategies to restore enamel in humans,” he said.
