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Table 1 Major transitions in the history of life and proposed Biological Big Bang events

From: The Biological Big Bang model for the major transitions in evolution

Transition/BBB Nature of the inflationary phase (dominant genetic exchange processes) Specifics/comments References
Emergence of complex RNA molecules and protein folds Recombination/fusion/fission, in the primordial gene pool, between genetic elements encoding short peptides and/or unstructured proteins, or RNA structural elements. The first of the three (along with the origins of viruses and cells) original, great BBBs that might have shared a physical substrate, the primordial gene pool, probably, abiogenically compartmentalized. This BBB would give rise to the tree pattern of evolution (gene trees) for the first time in the history of life. [43, 46, 115]
Emergence of the major classes of viruses Recombination and fusion, in the primordial gene pool, of genetic elements encoding hallmark viral genes. The second of the three great BBBs occurring in the primordial gene pool. [15]
Emergence of the two prokaryotic cell types, archaea and bacteria Recombination, fusion, and sorting of diverse genetic elements in the primordial gene pool. The third and last of the three great BBBs occurring in the primordial gene pool. Crucial processes involve the formation of selfish cooperatives, extensive transfer of genetic material between compartments, and sampling of genes into emerging protocells. Probably, numerous trials on cell formation, with only two types fixed. [15, 16, 19, 40, 41]
Emergence of the major lineages of archaea and bacteria Extensive gene exchange between protoarchaeal and protobacterial cells with leaky membranes within primordial microbial mats, possibly, in the vicinity of hydrothermal vents. Continued, albeit more constrained process of gene sampling, with numerous trials on more robust cells capable of departing the primordial mats.  
Emergence of the eukaryotic cell and the supergroups of eukaryotes Extensive gene flow from endosymbionts to the host chromosome(s) accompanied by massive invasion of introns and pervasive genome rearrangement. Distinct symbiotic events giving rise to the 5 supergroups of eukaryotes. The 5 eukaryotic supergroups are:
1. Plantae (green plants, green algae, red algae)
2. Chromalveolates (alveolates, including Apicomplexa, dinoflagellates, and ciliates, and stramenophiles including diatoms, oomycetes and many other groups)
3. Unikonts (Animals, fungi, Amoebozoa)
4. Rhizaria (Foraminifera and a variety of other, poorlycharacterized groups)
5. Excavates (kinetoplastids, euglenids, diplomonads, trichomonads, and other, poorly characterized groups) [28].
The chloroplast symbiosis, obviously, gave rise to Plantae, and a symbiosis between a primitive unicellular eukaryote and a red alga led to the emergence of the Chromalveolata. The remaining endosymbiotic events that are postulated to underlie the emergence of other supergroups might not have left morphologically distinct vestiges
[67, 70]
Origin of the major lineages within supergroups? Invasion of mobile elements; rewiring of regulatory networks; more?