work in progress
Well-Known Member
I wasn't aware of this thread before; but from what I've read, it's another god-in-the-gaps argument - since the pathway to the origins of life is still unknown, it's a gap in knowledge where the supernatural can be inserted.
But, over time, many previous gaps...like the so called irreducible complexities: the human eye, the blood-clotting cascade, and the little flagella motors that move many one celled bacteria, are mysteries that have been cleared up, or have many of the steps filled in, making them less fertile ground for supernatural arguments.
The Earth is estimated to be approximately 4.5 billion years old. There is evidence in the Western Australian desert of archaea (primitive bacteria) that lived 3.5 billion years ago. The implications are that life began on Earth very soon after meteor bombardments stopped and the surface was able to cool. And this is billions of years before the great diversity of life known as the Cambrian Explosion.
So, the picture of life on Earth is that simple one-celled life is easy to make, while the hard part is getting conditions right to support complex multicellular life forms. A recent lab study on possible abiogenesis pathways that I noticed on the Science + Religion blog, is leading to a conclusion that the road to the first life forms was likely not as "irreducibly complex" as many assume today, because it is apparently possible to create metabolic networks in the absence of RNA. Up till now, this has been a chicken and egg problem: how do you make the first self-replicating RNA molecules without metabolic processes in place/and how is metabolism accomplished except by RNA and later DNA?
But, over time, many previous gaps...like the so called irreducible complexities: the human eye, the blood-clotting cascade, and the little flagella motors that move many one celled bacteria, are mysteries that have been cleared up, or have many of the steps filled in, making them less fertile ground for supernatural arguments.
The Earth is estimated to be approximately 4.5 billion years old. There is evidence in the Western Australian desert of archaea (primitive bacteria) that lived 3.5 billion years ago. The implications are that life began on Earth very soon after meteor bombardments stopped and the surface was able to cool. And this is billions of years before the great diversity of life known as the Cambrian Explosion.
So, the picture of life on Earth is that simple one-celled life is easy to make, while the hard part is getting conditions right to support complex multicellular life forms. A recent lab study on possible abiogenesis pathways that I noticed on the Science + Religion blog, is leading to a conclusion that the road to the first life forms was likely not as "irreducibly complex" as many assume today, because it is apparently possible to create metabolic networks in the absence of RNA. Up till now, this has been a chicken and egg problem: how do you make the first self-replicating RNA molecules without metabolic processes in place/and how is metabolism accomplished except by RNA and later DNA?
Metabolic processes that underpin life on Earth have arisen spontaneously outside of cells. The serendipitous finding that metabolism the cascade of reactions in all cells that provides them with the raw materials they need to survive can happen in such simple conditions provides fresh insights into how the first life formed. It also suggests that the complex processes needed for life may have surprisingly humble origins.
Spark of life: Metabolism appears in lab without cells - life - 25 April 2014 - New Scientist