On his visit to the Galapagos Islands, Charles Darwin discovered several species of finches that varied from island to island, which helped him to develop his theory of natural selection.
The Galapagos Islands are an archipelago of 13 major islands and more than a hundred smaller islands that straddle the equator off the Ecuadorian coast. They are home to an amazing array of unique animal species: giant tortoises, iguanas, fur seals, sea lions, sharks, rays, and 26 species of native birds––14 of which make up the group known as Darwin’s finches. These finches are considered to be the world’s fastest-evolving vertebrates because their appearance and behavior quickly adapted to this closed and rapidly changing environment.
Today, Darwin’s finches are under attack from an introduced parasitic fly. Earthwatch volunteers helped to catch finches in mist nets (thin nets invisible to birds), measured them, took genetic samples, and recorded damage caused by the parasite before setting them free. They recorded and tested the function of finch song, collected data on the behavior of free-living wild finches, and helped determine the current numbers of finches on the islands. They also helped investigate evolutionary changes in Darwin’s finches. All of these activities provided vital information for the action plan being implemented by the Galapagos National Parks to ensure the survival of these iconic finches.
Similar expedition, Following Darwin’s Finches in the Galapagos, is accepting sign-ups right now!