https://blogs.scientificamerican.com/observations/a-science-based-origin-story-for-a-planet-changing-species/

David Christian is one of five expert speakers on Scientific American’s 175th Anniversary Cruise to the Americas in March 2020. For more information on our 175th Anniversary Cruise, including a detailed itinerary, seminar descriptions and speaker bios, click here.

During my lifetime—since the mid-20th century—we humans have suddenly become so powerful that what we do in the next 50 years will shape the future of all the species with which we share this planet. Whether we realize it or not, we have become the custodians of planet Earth.