Skip to main content

Origin of life on earth, part one

 


The origin of life on earth -- a lasting scientific mystery -- may have a lot to do with alkaline hydrothermal vents.  These are geysers-like vents found in the ocean floor. Marine biologists have long noted that they create the sort of chemically rich and energy intensive environment around them that mimics the electrochemical conditions found in cells. 

So ... maybe (thinking that thought in reverse) the cells of the world are indeed to this day mimicking that sea floor environment. 

In this context, with the vents themselves offering abundant energy, scientists can model the creation of RNA molecules, some of which prove to be self-replicating, although in a highly imperfect fashion.  Does it make sense to call this already "life"? Probably not.  Call it "proto-life" if you will.

There is some irony here, though. We often think of life as paradigmatically bound up with the absorption of sunlight. Light, through photosynthesis, becomes plant matter, which through digestion becomes animal matter.  It all begins with the sun.  Except, maybe it doesn't. Maybe life by way of proto-life, literally began in darkness, the deep darkness of the bottom of an ocean.   

For life in a full sense we'd presumably want to see the self-replication happen within discrete boundaries, separating the living process from its environment.  It would be life as something lived by a cell, with very real barrier although permeable in a pragmatic way letting nutrients in and waste out, rather than the reverse.

Once life in this sense emerged, it was self-contained enough to begin moving away from the vents, and perhaps toward the sunlight.  

Labels:

Comments

Post a Comment

Popular posts from this blog

Searle: The Chinese Room

John Searle has become the object of accusations of improper conduct. These accusations even have some people in the world of academic philosophy saying that instructors in that world should try to avoid teaching Searle's views. That is an odd contention, and has given rise to heated exchanges in certain corners of the blogosphere.  At Leiter Reports, I encountered a comment from someone describing himself as "grad student drop out." GSDO said: " This is a side question (and not at all an attempt to answer the question BL posed): How important is John Searle's work? Are people still working on speech act theory or is that just another dead end in the history of 20th century philosophy? My impression is that his reputation is somewhat inflated from all of his speaking engagements and NYRoB reviews. The Chinese room argument is a classic, but is there much more to his work than that?" I took it upon myself to answer that on LR. But here I'll tak...
24 comments
Read more

A Story About Coleridge

This is a quote from a memoir by Dorothy Wordsworth, reflecting on a trip she took with two famous poets, her brother, William Wordsworth, and their similarly gifted companion, Samuel Taylor Coleridge.   We sat upon a bench, placed for the sake of one of these views, whence we looked down upon the waterfall, and over the open country ... A lady and gentleman, more expeditious tourists than ourselves, came to the spot; they left us at the seat, and we found them again at another station above the Falls. Coleridge, who is always good-natured enough to enter into conversation with anybody whom he meets in his way, began to talk with the gentleman, who observed that it was a majestic waterfall. Coleridge was delighted with the accuracy of the epithet, particularly as he had been settling in his own mind the precise meaning of the words grand, majestic, sublime, etc., and had discussed the subject with William at some length the day before. “Yes, sir,” says Coleridge, “it is a maj...
10 comments
Read more

The Growing Block Theory of Time

My own disposition, in regard to the philosophy of time, is toward the "growing block" theory. This is the view that past events remain realities, that present-moment events are also realities, but that future events are not yet real. The image is of the universe as a block with an edge on (say) the right-hand side. The block is expanding because that edge is moving ever further right, and that edge is what we call the present, or, simply, "now." Everything to the left of that edge is both static (the past is complete) and, still and forever, real. Think of the phrase "the moving finger writes." The chief alternatives to the growing-block theory are "presentism" (only the now-edge itself is real) and "eternalism" (past, present, and future are all real." I believe that time is a growing block because (1) that's what it feels like, (2) we should stick with the introspective phenomenon unless we have good reason to abandon ...
8 comments
Read more