PMC

The analyses include data from sites where 15 or more sparrows have been sampled. The stippled lines show the significant regression lines for the European sites.

Arrows indicate mean values. The data were extracted from the MalAvi database . Logistic regression (estimate ± SE, P) on the likelihood of observing lineages in house sparrows; number of hosts (0.61±0.19, P = 0.001), America or Europe (−2.17±1.00, P = 0.030) and their interaction term (0.39±0.19, P = 0.043).

Dark green area shows natural range and light green introduced range. Sampling sites (black dots) and Plasmodium spp. lineage diversity within regions are illustrated by dotted lines (2–3 malaria parasite lineages), broken lines (4 malaria parasite lineages) and solid lines (8–9 malaria parasite lineages). The three sampled islands, Bermuda (B), Azores (A) and Faroe Islands (F), are indicated by arrows. The map is adapted from Glutz von Blotzheim et al. (1997) and Anderson (2006)

Regions with more than 40 sampled sparrows were included: South West Europe (swE), South East Europe (seE), South East Mediterranean (seM), North Europe (nE), North America (NAm), South America (SAm), Kenya (Ken) and New Zealand (NZ). Lineages recorded in single individuals were excluded (7 in Europe, 3 in N America, 2 in S America and 1 in India). The phylogeny was constructed from 479 bp cytochrome b sequences using Bayesian Inference and rooted with three lineages of Leucocytozoon (see Methods). Numbers at the nodes indicate the Bayesian posterior probabilities (%) and the scale bar the expected substitutions per site. Morphospecies identified by microscopic examination of blood smears are shown.