The origin of life

Assembled from 54 blocks · 5 evidence · 24 related

1. Story
2. Life is the only major transition in this Journey that is bracketed rather than dated, and the bracket is wide. The upper bound is set by the Moon-forming impact and the subsequent cooling of the surface enough to hold liquid water, somewhere after about 4.4 billion years ago on the evidence of the Jack Hills zircons. The lower bound is set by the oldest evidence a majority of workers accept — the roughly 3.48 billion-year-old stromatolites and microbial textures of the Dresser Formation in Western Australia. Between those two figures sit the disputed claims: carbon-isotope evidence at 3.7 Ga at Isua, structures interpreted as stromatolites at the same locality and challenged eight years later, and haematite filaments in Quebec that may be 3.77 or 4.28 billion years old. Molecular reconstruction adds a fourth kind of claim entirely, with a 2024 study placing the last universal common ancestor around 4.2 Ga. What no source anywhere provides is a horizon that could be called the origin: every line of evidence dates the presence of established life, not its beginning.
3. Knowledge
4. LUCA — the last universal common ancestor
5. Isua supracrustal belt, southwest Greenland
6. Nuvvuagittuq greenstone belt, Nunavik
7. Dresser Formation, North Pole Dome, Pilbara
8. Stromatolites
9. The origin of life
10. The Great Oxidation Event
11. Connections
12. Isua supracrustal belt, southwest Greenland
13. Nuvvuagittuq greenstone belt, Nunavik
14. Dresser Formation, North Pole Dome, Pilbara
15. The Great Oxidation Event
16. Dresser Formation, North Pole Dome, Pilbara
17. Isua supracrustal belt, southwest Greenland
18. Nuvvuagittuq greenstone belt, Nunavik
19. LUCA — the last universal common ancestor
20. Stromatolites
21. LUCA — the last universal common ancestor
22. Mass-independent fractionation of sulfur isotopes
23. Banded iron formations
24. The origin of life
25. Stromatolites
26. The Cambrian explosion
27. Endosymbiosis and the eukaryotic cell
28. Mass-independent fractionation of sulfur isotopes
29. Banded iron formations
30. The origin of life
31. The origin of life
32. The Isua stromatolite claim is reassessed and rejected
33. The origin of life
34. The origin of life
35. Carbon-isotope evidence reported from 3.7 Ga Isua sediments
36. Structures at Isua are reported as 3.7 Ga stromatolites
37. The Isua stromatolite claim is reassessed and rejected
38. The origin of life
39. The origin of life
40. Haematite filaments are reported from Nuvvuagittuq vent precipitates
41. Molecular clock dating
42. The Great Oxidation Event
43. The origin of life
44. LUCA is dated to about 4.2 Ga by phylogenomic analysis
45. The origin of life
46. The Great Oxidation Event
47. Structures at Isua are reported as 3.7 Ga stromatolites
48. The Isua stromatolite claim is reassessed and rejected
49. Evidence
50. Supports the carbon-isotope evidence for biological carbon fixation in more than 3.7 Ga Isua sediments. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked. Volume and page range are quoted from standing knowledge and were not re-checked.
51. Supports the reported identification of 3.7 Ga stromatolite-like structures at Isua. This record documents a claim that was subsequently contested; it is cited alongside EV_ALLWOOD_2018 rather than on its own. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked. Volume and page range are quoted from standing knowledge and were not re-checked.
52. Supports the reinterpretation of the Isua structures as deformation features rather than stromatolites, based on lateral exposure of the outcrop. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked. Volume and page range are quoted from standing knowledge and were not re-checked.
53. Supports the report of haematite filaments in Nuvvuagittuq jasper and the at-least-3.77 Ga and possibly 4.28 Ga age range of the host rocks. Both the biogenicity and the age are disputed in the subsequent literature, which is not cited here. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked. Volume and page range are quoted from standing knowledge and were not re-checked.
54. Supports the c. 4.2 Ga age estimate for LUCA and the inferred genome size and metabolic character. Deliberately cited without volume or page numbers, which were not confirmed. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked.