Coloured light microscopy of Plasmodium berghei protozoan. P. berghei is the parasite that causes malaria in mice. At centre is an exflagellating male gametocyte. It is developing into male gametes (microgametes, whip-like), the sexually reproductive form of the parasite. P. berghei is transmitted by the female Anopheles dureni mosquito. This stage of the parasite's life cycle takes place in the mosquito's gut, after it has ingested an infected bloodmeal. P. berghei cannot cause disease in humans but is used as a model organism for malaria research.