Reacción a "A Spanish study published in Nature reimagines the origin of our cells as a story of microbial alliances"

The work is sound, original and interesting. The origin of the eukaryotic cell is a mystery that has only been partially solved. The theory of the union between mitochondrial ancestors and archaea, pioneered by Lynn Margulis, opened the door to exploring the problem with unorthodox ideas. Instead of classical gradual transformations, she proposed the existence of phenotypic jumps resulting from fusions between organisms. Over the years, data has accumulated in support of this theory, but the complexity of the eukaryotic cell suggests that this ancestral fusion cannot account for that complexity.

This study presents solid and provocative evidence of several cycles of invasions and parasitic acquisitions that appear to predate the invasion that would give rise to mitochondria. Perhaps these invasions and fusions paved the way for subsequent ones. The putative role of viruses in these early evolutionary processes is particularly interesting, as they are known to have been involved in later ones.

The work is important not only because it adds significant data on the origin of a structure as complex as the eukaryotic cell, but also because it supports the notion of non-gradual, non-classical Darwinian processes in the emergence of complex structures and organisms.