The red blob in this picture is a human red blood cell, and the green blob in the middle of it is a pack of the malaria-causing parasites Plasmodium falciparum. Other species of the single-celled Plasmodium can give you malaria, but if you're looking for a real knock-down punch, P. falciparum is the parasite for you. It alone is responsible for almost all of the million-plus deaths due to malaria.
How did this scourge come to plague us? In a paper to be published this week in the Proceedings of the National Academy of Sciences, scientists have reconstructed a series of molecular events three million years ago that allowed Plasmodium falciparum to make us its host. They argue that a change in the receptors on the cells of hominids was the key. Ironically, this same change of receptors may have also allowed our ancestors to evolve big brains. Malaria may ...
