Most dinosaur fossils show bone. This one, a juvenile plant-eater from northeastern China, preserved individual skin cells inside hollow, porcupine-like spikes — a skin structure that existed for 125 million years without anyone knowing it was possible

Most dinosaur fossils show bone. This one, a juvenile plant-eater from northeastern China, preserved individual skin cells inside hollow, porcupine-like spikes — a skin structure that existed for 125 million years without anyone knowing it was possible

Most dinosaur fossils give us the scaffolding. Teeth, vertebrae and limb bones can tell palaeontologists how an animal fed, moved and grew, but they rarely preserve the surface that made the living animal recognisable. Haolong dongi is different. The newly described iguanodontian from northeastern China is represented by a nearly complete, articulated juvenile about 2.45 metres long. Around its neck, back and sides, the fossil retains scales int…