Native to the Sonoran Desert of the American southwest and Mexico, the Gila monster (Heloderma suspectum) might look and sound threatening. But to many, it’s known for its status as the largest lizard — and the only venomous lizard —native to the United States.
The Gila monster, distinguished by its black-and-pink patterned scales, spends the majority of its life beating the Arizona heat underground. Because of this, though, its habits have long been a mystery to scientists. Growing up to two feet long, the Gila monster’s size sets it apart from many other smaller, more agile Sonoran Desert lizards.
“They did not read the book on how to be a desert lizard,” says Dale DeNardo, an environmental physiologist at Arizona State University.
Yet what some consider to be its weaknesses are actually among the Gila monster’s greatest strengths. Unlike most of the world’s lizards, the Gila monster’s venom allows it to fend off predators despite its lack of agility. They’ve lived in the Sonoran Desert for millions of years, adapting over time to an increasingly arid environment and evolving to store water for survival in the hot, dry Arizona summers.
While many see them as a threat due to their venom, DeNardo and others say these “iconic” lizards could be facing even greater threats from ever-drier conditions due to climate change.
