Asteroid breakup linked to the Great Ordovician Biodiversification Event

Carbonates in Skeleton-Poor Seas: New Insights From Cambrian and Ordovician Strata of Laurentia

“…Our focus on skeletal chemistry does not by itself rule out hypotheses such as bolide facilitation of Ordovician radiation (Schmitz et al, 2008), although it highlights a specific pattern that such hypotheses must be able to explain. Nor does it rule out bottom-up proposals that link animal radiation to changing patterns of primary production.…”

Lower and Middle Ordovician conodont diversity of the Yichang Region, Hubei Province, Central China

“…Small 'sheet-like' structures ('mini mounds' sensu Lindström et al 1991) and fold structures (= 'buckled beds' of Lindström et al 1991) characterize the middle part of the Puxi member (Lindström et al 1991, Zhang 1996. Schmitz et al (2008) recorded high concentrations of L-chondrites in the middle member from the Puxihe section; the concentration of L-chondrites is found within the Lenodus variabilis and Yangtzeplacognathus crassus conodont zones of Zhang (1998).…”

“…Thus, another cause may be the explanation for the high diversity. Schmitz et al (2008) recorded a high concentration of extraterrestrial chromites, representing meteorites, from this interval in the Yichang area. The cromites were interpreted to be the product of the largest disruption in the asteroid belt and considered possible triggers for the Middle Ordovician biodiversification of shelled invertebrates (Schmitz et al 2008).…”

“…The Ordovician conodont faunas of the Yichang Region are known from mainly four closely spaced sections: the Huanghuachang, Chenjiahe, Puxihe, and Fenxiang sections ( Fig. 1) , Lindström et al 1991, Schmitz et al 2008, Zhang 1999. Generally, the yield of conodonts from these sections is high, but research on conodonts from the sections is not yet completed (Stouge et al in prep.…”

Genesis on Diamonds

“…Clearly, both organization processes must occur in a biorelevant environment, that is, a wet milieu, and both are energyconsuming. Interestingly, a hostile planetary environment such as the primitive Earth, subject to rapid changes, including but not limited to volcanic and hydrothermal activity, 3 acidic atmosphere, and virtually planet-sterilizing meteorite impacts, 4 favors precisely the conditions necessary for the formation of first ordered structures, regarded as possible starting points of biological evolution. In recent laboratory experiments we found evidence for the establishment of nanoscopic crystalline interfacial water layers on hydrogenated nanocrystalline diamond at room temperature.…”