Jamesian Philosophy Refreshed

Yesterday we asked when and how life on earth began.  We didn't answer that question.  We offered a scenario for a proto-life, but also noted that much more would have to happen for that to become cellular life as we generally understand the term.  It is possible that life -- considered as something DISTINCT from the proto-life I discussed yesterday, had two origins. There were two paths forward, so to speak, bacteria and archaea. The bacteria developed first.  Muh later, the archaea developed and absorbed the bacteria so the later became the energy producing part (the mitochondria) of larger cells.   As to the timing?  The best guess sets the early RNA replication (proto-life) at about 4 billion years ago.  There were complicated cells, leaving a fossil record, by 3.5 billion years ago, so each of the two paths described above had been executed by then. IF any of this is right.  Science proceeds by falsification, and this all may be falsif...

  In a recent study published in Proceedings of the National Academy of Sciences, (PNAS), scientists at the Carnegie Science Institute claim that chemical signs of photosynthesis, and so of life, have shown up in rocks at least 2.5 billion years old. Vegetative life existed on earth that far back. Until now, photosynthesis was generally traced back only to 1.7 billion.  "Good for the scientists," you might say, "it clearly helps make them stand-outs within their special field of study.  But should it matter to the rest of us?" I submit that it should.  One reason is that as one pushes back the dating of the earliest emergence of life, one shortens the amount of time for the chemical, pre-biological evolution that may have been necessary to get the history of life underway. How long a span of time is necessary for life to emerge on a planet, when circumstances (such as the distance to the nearest sun, the size of that sun, etc.) are amenable? There is only one case ...

An old joke comes to mind.  The joke is from a comedy team that once had a primetime television show but that has now been largely forgotten. Burns and Schrieber.  "Is there life on Mars?" "Only on Saturday night." ----------------------------------------------------------------- Less amusingly: NASA's Perseverance rover has been analyzing the chemistry of a rock they call Cheyava Falls, within the Jezero Crater.  Those names mean nothing to you?  Fair enough. What may mean something, though, is the fact that Cheyava Falls shows evidence of the passage of water through porous rock. and contains organic compounds, i.e. compounds that on earth would be associated with life.    "Are we alone in the universe?" "No, but the neighborhood has been pretty dead lately."  

  The Future of Humanity Institute has shut down.  Oh, what a rough sentence to write! An organization devoted to ensuring that we as a species has a future ... now officially has only a past.  FHI was a multidisciplinary research center at the University of Oxford. And apparently one of the recurrent themes in the Institute's research was the "Fermi paradox." This is the idea that, on the one hand, there SHOULD BE technologically sophisticated aliens Out There, but that on the other hand we don't hear from them.  As FHI bigwig Robin Hanson has put it: there must be a filter. Something is preventing our approach and likely our colonization by such beings. It is possible that intelligence, and so advanced technology, is much more rare than exobiologist have tended to assume. In THAT case, this is something about life we should want to know. On the other hand, it is possible that the filter is still in our future. Perhaps once a species becomes sufficiently advanced, i...

The case that we have already met it.   (PDF) Fungi on Mars? Evidence of Growth and Behavior From Sequential Images (researchgate.net)