Why did Charles Darwin spend much of the Beagle voyage exploring on land?

Charles Darwin spent much of the Beagle voyage exploring on land primarily because he served as a gentleman naturalist, a role that granted him the freedom to leave the ship for extended periods to pursue his own scientific interests. Additionally, Darwin suffered from severe, tormenting seasickness while at sea, which made life aboard the vessel difficult.1

By spending time ashore, Darwin was able to conduct extensive field research that would have been impossible from the ship. He utilized these opportunities to explore diverse environments, such as the Brazilian rainforests and the Andes Mountains, where he collected specimens and made observations that were essential to his later work on the theory of natural selection. As a result of these excursions, Darwin spent only 18 months of the five-year voyage actually aboard the ship.21