Twelve miles from the heart of Rome, Dr Javier Ábalos pauses his walk, lifts his sunglasses and points. To his right, perched on a rocky wall, sits a beautiful lizard. Its body is coated in charcoal-black tones speckled with striking yellow across a green dorsum, and its head, with a prominent jaw, is splashed with fluorescent blue spots. The reptile basks in the sun, unconcerned by our presence.
About 80 miles (130km) drive farther along the road that connects the capital with the small village of Poggio di Roio, the researcher from the University of Valencia has barely stepped out of the car when he spots another lizard. This one is smaller, with a brownish body and a narrower head crisscrossed by a network of dark stripes.
