PortalsOS

Eukaryotes are significant because they represent a singularity in the history of life on Earth, arising once about 2 billion years ago. This event gave rise to all complex life, despite bacteria and archaea having a greater genetic repertoire.

The difficulty of successful endosymbiosis, where one cell engulfs another, is a significant barrier to complexity. While this may have occurred many times, it often fails, leading to the loss of the endosymbiont.

The Earth acts like a giant battery, producing little living cell mini-batteries through hydrothermal vents. This fascinating theory suggests that the structure of cells mirrors the Earth's own structure, with electrons inside and a relatively oxidized outside.

Bacterial evolution is fascinating because they maintain small genomes but have access to a large pan genome. For example, an E. coli cell might have 3,000 to 4,000 genes but access to 30,000 to 40,000 genes. This allows them to adapt by borrowing genes from other strains, which is crucial for survival in different environments.

The continuity between geological environments and cells suggests that life forms are continuous with Earth's geochemistry, challenging the idea of a 'Frankenstein moment' where life suddenly zaps into existence.

The necessity of large genomes in multicellular organisms is driven by the need to minimize genetic conflict between cells, ensuring that all cells work towards the same goal of survival and reproduction.

The emergence of eukaryotes is seen as a major bottleneck in the development of complex life. Despite the vast number of planets that could potentially give rise to eukaryotes, it seems this event is incredibly rare, with Earth being a unique example.

Nick Lane explains that protocells in hydrothermal vents could self-organize and grow by deterministic chemistry, leading to early forms of heredity. This sets the stage for more complex life forms.

The Asgard Archaea, discovered about ten years ago, are fascinating because they exhibit some eukaryotic-like features, such as similar proteins and genes, yet they remain fundamentally prokaryotic in complexity.

Despite the vast number of planets, the unique development of eukaryotes on Earth suggests that while other methods of achieving complexity might exist, they are not easily realized in nature.