Are host-parasite systems more specialized in the tropics than in the temperate zones?  We asked this question using community-wide data on avian malaria parasites in the Ecuadorean Amazon and in the Ozarks.  In both systems we found that host-parasite were highly specialized, much more so than expected by chance.  Tropical birds also tended to have greater parasite diversity than temperate host species. However, taking the view from the parasite, tropical and temperate systems showed similar levels of specialization.  The work was led by Dr. Maria Svensson-Coelho as part of her dissertation research in the lab of Dr. Robert Ricklefs at University of Missouri-St. Louis.  Our lab contributed data on malaria parasites from 2488 individual birds representing 104 species at the Tiputini Biodiversity Station in Yasuni Biosphere Reserve.  Read more about these results here in our paper, Reciprocal specialization in multihost malaria parasite communities of birds: a temperate-tropical comparison, published in American Naturalist by Maria Svensson-Coelho, Vincenzo Ellis, Bette Loiselle, John Blake and Robert Ricklefs.
Fig 2 Svensson-Coelho et al. Am Nat 2014 Pithys_albifrons