If you thought that a 80kg reptile sounded impressive enough, scientists have now discovered that the world’s largest lizard, the Endangered Komodo dragon, have iron-tipped teeth – and a resident at London Zoo was central to this exciting new finding.
London Zoo’s team were part of new research, led by King’s College London, studying the teeth of these giant monitor lizards native to Indonesia.
Komodo dragons have 60 serrated teeth which they use to hunt and eat a wide variety of prey. By using state-of-the-art technology to study the teeth of Komodo dragon Ganas, along with various skulls and teeth from museum collections, the team found highly concentrated amounts of iron on each tooth, creating a thin metal coating along the tips and cutting edges.
This iron acts as a protective layer, helping the dragons ensure their teeth are sharp and ready to be used – whether that’s for making the most of a scavenged carcass, hunting prey or defending themselves during a fight.
This finding not only helps us build a stronger understanding of this endangered species, but also opens new exciting avenues for research into how extinct dinosaurs such as Tyrannosaurus rex lived. While current technology means scientists can’t determine whether fossilised dinosaur teeth have high levels of iron, it’s hoped that by studying Komodo dragon teeth further they’ll be able to identify alternative methods that will provide fascinating insights into how these predators killed and ate their prey.
Ganas the Komodo Dragon
Much loved by keepers and visitors alike, Ganas came to London Zoo from Denmark in 2015.
Surprisingly, Ganas didn’t have a father; female Komodo dragons are able to lay fertile eggs without a male – an unusual tactic that means they can still reproduce in the wild, even when there aren’t many males around. Known as parthenogenesis (literally meaning “virgin-creation"), this tactic can be seen across the animal kingdom, but was first confirmed in Komodo dragons in 2006 when two females, including one at London Zoo, laid eggs - despite the fact that, as solitary animals that live and hunt alone, they were both on their own at the time.
Ganas lived at the Zoo until 2022, when it was sadly discovered that he had an untreatable form of degenerative arthritis, and euthanasia was decided to be the kindest outcome.
In addition to his teeth being used in this study to understand more about these fascinating animals, scans from Ganas’ diagnosis have been shared with wildlife vets and conservationists across the globe, helping develop a stronger understanding of both this threatened species and disease in reptiles.
The World’s Largest Lizards
Weighing up to 80kg and 3m in length when fully grown, Komodo dragons are both the world’s heaviest and largest lizards. Adult Komodo dragons feed on carrion, along with hunting animals such as wild pigs and deer, with their sharp, curved teeth causing prey to quickly bleed out.
As scavengers and apex predators, Komodo dragons play an important role in their ecosystems – helping both remove the carcasses of recently dead animals (that could otherwise become sources of disease), and keeping the numbers of herbivores on the islands in check.
Dragons Under Threat
These impressive lizards are sadly at risk of extinction. Komodo dragons are listed as Endangered on the IUCN Red List as a result of threats including habitat loss, overhunting and competition with humans over prey. Climate change also poses a threat, with rising sea levels threatening to submerge their island habitats. In 2021, there were estimated to only be 1,400 Komodo dragons left in the world.
Conservationists from ZSL, the international conservation charity behind London Zoo, are working to protect the Komodo dragon’s native Indonesian habitat. Over 90% of palm oil is grown in Southeast Asia, and we’re working with the palm oil industry to advise on best practice for protecting wildlife, alongside greater transparency around sustainably practices. We also support the Komodo Survival Program, an Indonesian non-profit organisation which delivers science-led conservation for Komodo dragons.
Visitors wishing to learn more about these awe-inspiring lizards and the threats they face can head to London Zoo to come face-to-face with 1.5 meter long female dragon Khaleesi, who calls the zoo’s Attenborough Komodo Dragon House home.
Every ticket to London Zoo helps support our ongoing science and conservation work to protect wildlife across the globe.