What are pros and cons of how humans affect the earth?

Answer 1

I'm not sure there are really many (or any) pros, most of what could be considered a pro, such as saving endangered species was a problem caused by Man to begin with with deforestation or introduction of foreign animal invaders to ecosystems. Some day we may bring back extinct animals (or plants, but unlikely) and then we'd be truly benefiting the Earth. If some day we're able to keep large asteroids or comets from hitting Earth and destroying it that would be a major "pro" but so far we don't have that technology either. I guess one "pro" could be that we humans can make deserts bloom and actually alter the terrain and reforest areas destroyed by fires, volcanoes or human caused deforestation, but at the same we often cause desertification and deforestation too. The amount of deforestation going on in the tropical regions where there's a diversity of life not seen anywhere else is one of the worst travesties caused by Man; animals and plant species that will go extinct or become endangered that we may not even know of. Some of these animals and plants may have even contributed to new medicines or technology. One "pro" humans often unintentionally do is the sinking of ships creating artificial reefs that harbor life. Also, some nuclear power plants along the East coast and Florida create warm bays and estuaries for manatees. Maybe some day we'll make the Moon or Mars bloom but I seriously doubt it, or if we do it'll be small scale "greenhouses" and so expensive and unlikely to succeed we'd eventually give up.