Evolution of DNA - Cellular Explosion

Introduction
First Protein Transcription
First Genetic Replication
First Feedback
Puddle Evolution
First Dispersal & Evolution
First Parasite
First Organism
First Cell Metabolism
First Self-Sufficiency
Aromatic Assistants
First Assimilation
First Transfer Molecules
Eight Molecule Life
Complementary Base Pairs
Energy Sources
Conquering the Oceans
First Cells
Cellular Explosion
Gene Regulation
Chromosomes
First DNA
Introns
Wider Reading Frames
Complementary Triplets
Cellular Scripts
The Spread of Foxy
Second Parasite-- Transposons
First Schism
Improved Gene Regulation
Cell Structures
Eukaryote Explosion
Multi-Cellular Scripts
Cambrian Explosion
Epilog
Appendix 1-- Prebiotic Earth
Appendix 2-- Primordial Puddles
Appendix 3-- Primordial Catalysts
Appendix 4-- C Value Enigma
Cast of Characters

The emergence of an ocean-worthy cellular Cassius would have opened a huge volume of potential habitat to the early life forms. You might say it produced the fourth explosion of new life forms that expanded and filled the waters of the early Earth.

During the first Fred/Roscoe explosion there may only have been hundreds or thousands of organisms on the entire Earth, since they could only survive in a few shoreline pools with exactly the right conditions. In fact, because it was so difficult for the individual molecules to diffuse simultaneously into the same puddle, it's possible that they never expanded outside their original neighborhood.

The Caleb and early Cassius explosions would have kicked the populations up a notch, since they could thrive in more types of puddles, and since they could bring along most of what they needed in a single package.

However, once Cassius was freed from the occasional specialized puddles, it could have potentially increased its population to exponential levels. Having just one cellular Cassius per liter of ocean would have meant there were 1021 individuals floating around (or about a sextillion cells).

With such a huge pool of different Cassius organisms, the pace of evolution would have increased enormously, simply because there were many more organisms in which improvements could appear. Different versions of Cassius in different habitats would have evolved different features or different metabolic strategies, and the era of plain old Darwinian selection would be at hand.

Evolutionary Speed

How long would it have taken from the first Fred and Sofia combination to the first cells capable of replication and metabolism?

If we are willing to lower our definition of life to a bare minimum, it may not have taken long at all, at least in a geological sense.

The ratio of carbon isotopes in extremely old rocks dating from 3.85 billion years ago seems to indicate that life may have already evolved by that time.

Advanced versions of Cassius would be already be capable of performing metabolism which would change the carbon isotope ratio, and it's possible that the entire progression from Fred to Cassius may have happened extremely quickly-- in tens of millions of years or less. There are quite a few steps to the transformation, but none of them are sufficiently improbable that they would have taken billions of years.

Multiple Waves

Once an evolving, cellular version of Cassius was on the scene, there would have been many successive waves of more efficient versions of Cassius, each expanding geographically into a wide range of habitats, and becoming the dominant life form, at least until the next Cassius came along.

As Cassius and its progeny gradually developed more metabolic enzymes and started to eat their surroundings, they would have digested the last of the primordial soup and converted it to biomass. With all organic compounds now created by enzymes, the last of the older, racemic chemistry would have disappeared from all but the most isolated nooks and crannies of Earth.