Which South American country has the highest biodiversity per square kilometer? The answer is Ecuador.
Ecuador is widely described as the world’s most biodiverse country relative to its area, using species richness per square kilometer as the comparison. Its compact territory contains an exceptional range of environments: Pacific coast, Andean highlands, Amazon rainforest, and the isolated Galápagos Islands.
The Andes create dramatic changes in altitude and climate over short distances, producing many separate habitats. Ecuador is one of the world’s 17 megadiverse countries and is especially notable for its concentration of birds, amphibians, reptiles, plants, and butterflies. The Galápagos adds another layer of uniqueness through species that evolved in isolation.
The phrase “most biodiversity” can be misleading if it means total species count: larger countries such as Brazil may contain more species overall. Ecuador’s distinction is density, not necessarily the greatest absolute number. Commonly cited figures include about 1,600 bird species, more than 16,000 plant species, and thousands of butterfly species.