A Great late Ediacaran ice age

A Great Ediacaran Glaciation (GEG) lasting at least 20 million years from continent to continent in mid-to-high latitudes witnessed the evolution of the Ediacara biota. The emergence of the Ediacara biota soon after the Gaskiers glaciation ca. 580 million years ago (Ma) implies a possible glacial fuse for the evolution of animals. However, the timing of Ediacaran glaciation remains controversial because of poor age constraints on the similar to 30 Ediacaran glacial deposits known worldwide. In addition, paleomagnetic constraints and a lack of convincing Snowball-like cap carbonates indicate that Ediacaran glaciations likely did not occur at low latitudes. Thus, reconciling the global occurrences without global glaciation remains a paradox. Here, we report that the large amplitude, globally synchronous ca. 571-562 Ma Shuram carbon isotope excursion occurs below the Ediacaran Hankalchough glacial deposit in Tarim, confirming a post-Shuram glaciation. Leveraging paleomagnetic evidence for a similar to 90 degrees reorientation of all continents due to true polar wander, and a non-Snowball condition that rules out low-latitude glaciations, we use paleogeographic reconstructions to further constrain glacial ages. Our results depict a 'Great Ediacaran Glaciation' occurring diachronously but continuously from ca. 580-560 Ma as different continents migrated through polar-temperate latitudes. The succession of radiation, turnover and extinction of the Ediacara biota strongly reflects glacial-deglacial dynamics.

Automated summary

A Great Ediacaran Glaciation, lasting for 20 million years, occurred globally from mid-to-high latitudes, witnessing the evolution of the Ediacara biota. The timing of Ediacaran glaciation remains controversial due to limited age constraints and a lack of convincing evidence for low-latitude glaciations. However, recent studies using carbon isotope excursions and paleomagnetic evidence suggest that the Ediacaran glaciation occurred diachronously but continuously from ca. 580-560 Ma as different continents migrated through polar-temperate latitudes.