In their exploits intrepid researchers seek new answers from our ancient past, in the desperate hope of saving Earth from a devastating cosmic disturbance. OutTack - a novel by GS Boughton, in the DeepStorm trilogy, in which the Questor mission's Chief Scientist and reconneers in 2066 views the Earth's timeline of evolution and episodic mass extinctions in prehistory - those of reptiles, non-avian dinosaurs included, in the Cretaceous - all through the planet's terraforming of the biosphere, whether caused geologically by surface upheavals or major impacts from bolides (asteroids, meteorites, comets), while discounting climactic causes or biodiversity crises, and considers the likelihood of such global catastrophe being cyclical, and so an ongoing threat to humanity.

Fossils -- as telltale signs of mass extinctions, whether caused by major upheavals geologically or from conflicts amongst underdeveloped eustatic Precambrian colonies terraforming the biosphere -- are rare. And, as such, there are no indications of catastrophic events prior to the End Precambrian, when the 1st mass extinction is known to have taken place. All known events were subsequent to that.