In the last remaining pockets of natural grassland in southeastern Australia lives a lizard so small it can hide in spider burrows. Inside the burrows, the grassland earless dragon, which weighs barely more than a quarter, finds shelter from the extreme temperatures found on the plains.

The grassland earless dragon, which gets its name from its scale-covered ears, is very hard to find because of its reclusive lifestyle and camouflaged appearance, says ecologist Will Osborne of Australia’s University of Canberra. So difficult to find, in fact, that the lizard went undocumented for about 30 years until Osborne and his colleagues rediscovered it in 1991.

It turns out that what scientists long thought was a single, elusive species of lizard living in southeastern