Imagine a future where the heads of Bill Nye and Neil deGrasse-Tyson are attached to robots to lead a space mission to colonize another planet. When they get there they find a pristine planet like Earth used to be. Forests, rivers and oceans all in their natural state, with no forms of intelligent life present.
They land the ship and set up their colony as happy as they can be. Unfortunately, the Bill Nye and Neil deGrasse-Tyson robots take the first opportunity they get to jump off a cliff, as they were tired of life. (A tragic story really. The crew of the ship had to be constantly vigilant, making sure the robots didn’t kill themselves or jeopardize the mission in anyway because they were so depressed. The robots learned the hard way that the human mind was not meant to live so long, and that the belief in an afterlife was the best coping mechanism for a necessary and inevitable death. The robots kept saying, “We’re tired. We want to die.” The people would ask why they would want to die, and not having a sound logical answer they would say, “We want to go to heaven to see our families.” The people on the ship would lock them down every night telling them, “You are being silly. There is no heaven, remember? You are the ones who convinced us of that.”) Still, everything seemed to be perfect until the first people started to show signs of fatigue, and then illness. They became frantic in trying to understand the cause. They figured it was a microbe or virus and they scoured their environment with microscopes, looking for the culprit.
Thousands of years later, another alien species landed on the planet and found the remains of the Earth colony. After much research and investigation they determined that the Earthlings landed there as an emergency. They concluded this because their biology was not adapted to an environment without complex chemicals present, and they couldn’t imagine that an advanced society, one that could travel the stars, would choose to set a colony up on a planet that was so toxic to them.
On the home planet of those other aliens, many centuries passed in friendly debate about what the chemistry of Earth must have been like to have evolved such creatures, and how that chemistry could have formed that way naturally.