A group of biosphere conservation activists from a type three civilization come across the earth. Using their technology and observations, they see that throughout human history , humans have blatantly disregarded the well being of their fellow multi-cellular life forms , and due to this , they are leading their biosphere down a path of self destruction. they are outraged and greatly desire to safe the biosphere , but due to intergalactic bylaws , they are not allowed to
A) Directly interact with any civilizations below type 1
B) Disrupt the natural ecology of any planet or Moon that they are not native to
C) Land any Individual or Craft on th any planet or Moons whose inhabitants have not reached Type 2
D) Tamper with the orbits of any bodies in a solar system that contains lifeforms below type 2
The violation of one or more of these laws could result in anything from planet arrest ( where the perpetrator(s) may not leave the planetary system of their home world ) for 150 years , to digital purgatory ( where their consciousness is uploaded to a matrioshka brain to survive as primeval sapiens until the heat death of the universe ).
My question is: what is the least Impactful thing that could be done to wipe out the human race without disrupting the natural world?
- Note:All "type" figures are in terms of the kardashev scale of civilizations