Tiny tyrannosaur fossil helps scientists understand how T-rex grew so large; Art gets a bad case of acne and it has conservators concerned; Zebra stripes confuse tiny predators, not the big ones;Scientists can read the 'rust' on a person's DNA to predict when they'll die; Hacking photosynthesis to re-engineer crop plants and feed the world; What would it be like to stand on the surface of the sun?