Bilirubin is the end product of heme catabolism and originates primarily from the breakdown of erythrocyte hemoglobin in the reticuloendothelial system. A smaller, yet significant, proportion is ...

Two points in your article about our work on Bili’s “giant apes” require correction (1 July, p 14). It is an exaggeration to say that the chimps’ skulls have a sagittal crest. Only one skull has been ...