The House Sparrow's natural distribution covers much of Eurasia and through introductions elsewhere, this species has achieved near world-wide occurrence. Its appearance in South America began with introductions of 20 pairs in 1872 (or 1873) in Buenos Aires, Argentina. Additional introductions at Santiago, Chile, in 1904 and Rio de Janeiro, Brazil, in 1905, and with human assistance -- both intentional and unintentional -- and natural spread following roads and railroads and allowed this species to colonize much of the continent -- from western Colombia, central Bolivia and eastern Brazil south through Chile and Argentina. Populations originating from their 1852 introduction in New York, U.S., reached Mexico in about 1910 and have spread southward and have reached Panama in the 1980s.
House Sparrows have been subject of many studies in Europe and North America, especially, but very little work has been done on Neotropical populations. The House Sparrow is a temperate species and its appearance in tropical latitudes and habitats provides for interesting natural experiments.