Australian researchers from the University of Queensland have uncovered how varanid lizards, including Komodo dragons, survive bites from Australia’s most venomous snakes. The findings appear in the International Journal of Molecular Sciences.
Australia hosts some of the world’s deadliest snakes, with the taipan earning a notorious reputation for delivering the largest amount of toxin per bite. A single venom dose has the potential to be lethal to dozens of people if left unchecked.
The study reveals that many large monitor lizards, known as varanids, possess an inherent resistance to neurotoxins, a trait tied to their feeding strategies and predatory habits.
Researchers found that different varanid species exhibit varying levels of adaptation to the primary venom weapon of snakes. Komodo dragons, for instance, show greater vulnerability to neurotoxins yet compensate with a nearly impenetrable armor against snake fangs, while their strong jaws and sizeable teeth enable effective bites on snakes themselves.
Some smaller tree-dwelling monitors have apparently lost chemical resistance to certain poisons but thrive in arboreal environments where snakes have limited access. In contrast, terrestrial relatives have developed stronger immunity to venom over time, illustrating how habitat shifts influence venom resistance.
The researchers also describe an ongoing evolutionary arms race between snakes and lizards, with each lineage evolving new strategies for offense and defense as they interact in shared ecosystems.
Earlier work in this area highlighted the development of universal antidotal approaches for major snake venoms such as those from the black mamba and the king cobra. The new findings build on this by detailing how reptile physiology adapts to venom exposure in natural settings, underscoring the dynamics of predator–prey interactions in Australian habitats.