Which sphere are humans part of ? in which sphere humans live?

Consider that human beings or living organisms live in the biosphere. Biosphere is the collective group of living organisms and their interaction to one another and –ecosystem- to their environment. Human beings like animals or plants are part of the biosphere, one of the spheres in the earth. We have the atmosphere (air), lithosphere (land), hydrosphere (water) and the biosphere (life/ living organisms). Each is with a specific and distinctive characteristics to play in the earth’s existence at the current era.

Southern secession is the event or issue that historians can gain insight from this excerpt.