Four years ago, at age 12, Miguel Avelas gave paleontologists in Patagonia, Argentina, a huge surprise. He led them to a place where they found hundreds of 90-million-year-old fossils of lizardlike reptiles called sphenodontians. Scientists had thought that the reptiles had disappeared 120 million years ago. The discovery was published this month in the science journal Nature.
"It was fantastic," says paleontologist Sebastian Apesteguia. "We had no idea that sphenodontians could possibly be found there."
Several of the fossilized skeletons were nearly complete and as long as three feet. The sharp-toothed reptiles lived alongside dinosaurs and crocodiles.