Darwin collected everywhere the ship landed. He found huge fossils of recently extinct mammals, experienced an earthquake in Chile, and noticed the land had been raised. He knew of raised beaches elsewhere, high in the Andes, with fossil seashells and trees which had once grown on a sandy beach. Obviously the earth was constantly changing, with land rising in some places, and sinking in others. He collected birds and insects, and sent shipments back to Cambridge for experts to identify.