Are Habitable Exoplanets Bad News For Humanity?

An anonymous reader writes "The discovery of Kepler-186f last week has dusted off an interesting theory regarding the fate of humanity and the link between that fate and the possibility of life on other planets. Known as the The Great Filter, this theory attempts to answer the Fermi Paradox (why we haven't found other complex life forms anywhere in our vast galaxy) by introducing the idea of an evolutionary bottleneck which would make the emergence of a life form capable of interstellar colonization statistically rare. As scientists gear up to search for life on Kepler-186f, some people are wondering if humanity has already gone through The Great Filter and miraculously survived or if it's still on our horizon and may lead to our extinction."

Comments

The Nature of the Fermi Paradox

[crunchygranola]

The core of the Fermi Paradox is that there does not appear to be any basic physical limitation that would prevent an intelligent civilization from colonizing the entire galaxy in much less than a 100 million years - yet there is no case that can yet be made that Earth is anything like a boundary case of the "earliest possible biosphere". It is not a solution to the Fermi Paradox to postulate reasons why one intelligent species or another might fail to do so, it has to apply to every one of them since one outlier would go on to colonize the galaxy.

I think part of the resolution of the paradox is the implicit notion common to us humans that our form of tool-using symbolic-communicating intelligence is some sense "inevitable" and will arise given enough time. Yet observing the evolution of the large animals on Earth does not give any reason for thinking this is some sort of normal progression. The Great Apes, very similar to hominids, have not shown any trend toward evolving larger brains since the hominid-ape split 7 million years ago. No general trend toward developing human style intelligence is evident anywhere. The emerging story of hominid development is that a long series of lucky accidents seems to have been necessary to bring it about.

Human-style intelligence may be extremely unlikely to evolve at all.