Electrophoretic patterns of blood proteins were compared among groups of Arvicanthis niloticus from widely distant origin: Senegal, Haute-Volta, Egypt. Four blood proteins/enzymes were studied: albumin, transferrin, esterase and 6-phosphogluconate dehydrogenase. The results demonstrate two levels of difference: (a) inter-population differences; and (b) intra-species genetic polymorphism. The latter was not observed for all populations nor for all loci. The differences between populations suggest that some process of specification could be under way among Arvicanthis.

Les resultats des analyses univariees et des tests de Mann et Whitney sont en faveur d'un cline de taille croissante d'est en ouest de l'Afrique. Les resultats des analyses des correspondances permettent de mettre en evidence: des differences de taille (les individus du Senegal sont les plus grands); des differences de proportion des dents, du crâne et du reste du corps; des differences de proportions des os des membres et des autres mensurations