The text begins with the arrival of Charles Darwin to the Río de la Plata, in 1832, aboard the sailing ship Beagle. At age 23, Darwin entered the lands populated by gauchos and wild animals. He traveled on horseback or by cart in the territories of Maldonado, Lavalleja, Colonia, Soriano, San José, and Montevideo. He discovered animals he had never seen, such as capybara, recognized fossils and marveled at certain local customs. Upon his return to England, and from the rich experience he had lived, he developed the theory of evolution, whose foundations are applied today in biological research.