A new specimen of one of the most controversial species of dinosaur has the potential to overturn decades of research on the T rex. Nanotyrannus, the “miniature T rex”, has been the centre of one of the fiercest debates in palaeontology. Scientists have long argued over whether the Nanotyrannus is a separate species or just a young T rex. But the debate surrounding the identity of Nanotyrannus may finally be settled. A new fossil specimen is the smoking gun researchers have been looking for: an