Special Issue: Early Evolution and the Last Common Ancestor

The early evolution of life spans an extensive period preceding the emergence of the first eukaryotic cell. This epoch, which transpired from 4.5 to 2.5 billion years ago, marked the advent of many fundamental cellular attributes and witnessed the existence of the Last Common Ancestor (LCA) of all life forms. Uncovering and reconstructing this elusive LCA's characteristics and genetic makeup represents a formidable challenge and a pivotal pursuit in early evolution. While most scientific accounts concur that the LCA resembles contemporary prokaryotes, its precise definition, genome composition, metabolic capabilities, and ecological niche remain subjects of contentious debate.

In this thematic discussion, we invite several distinguished global experts to expound upon their research findings and perspectives in this field.

This Special Issue will attempt to shed light on Early Evolution and the nature of life's Last Common Ancestor.

Including but not only the following subjects:

1) Definitions and notions:

• The Last Universal Common Ancestor and the first branch on the tree of life.

• The nature of the Last Universal Common Ancestor and related concepts (i.e., single organism, single population, or methodological artifact).

• Minimal life as a proxy for the Last Universal Common Ancestor

• Last Universal Common Ancestor, best practices, and future developments.

2) The nature of the Last Common Ancestor:

• What was the nature of the genome of the Last Universal Common Ancestor?

• What were the metabolic abilities of the Last Universal Common Ancestor?

• Processes of molecular evolution at the time of the Last Universal Common Ancestor.

• The state of cellular systems and functional networks at the time of the Last Universal Common Ancestor.