Fig. 3

Reciprocal positive effects on parasitemia between H. passeris and P. relictum in adult house sparrows. The infection intensity (log 10 parasitemia) in adult house sparrows (A) blood positive with H. passeris (green) in relation with the infection intensity of P. relictum (log 10 parasitemia and also including non-infected individuals in this parameter, i.e. both blood positive and blood negative) and (B) blood positive with P. relictum (blue) in relation with the infection intensity of H. passeris (log 10 parasitemia and also including non-infected individuals in this parameter, i.e. both blood positive and blood negative). Both the positive correlations are significant and the grey area indicates the 95% confidence intervals (N = 19 adult house sparrows)