The Search for Sedimentary Evidence of Glaciation during the Frasnian/Famennian (Late Devonian) Biodiversity Crisis

The cause of the Late Devonian (Frasnian/Famennian) biodiversity crisis remains controversial. Over 36 years of amassed empirical biological data have been used to argue for a causal link between global cooling and the Frasnian/Famennian extinctions (for a review of the data see McGhee 2013, 2014). In particular, glaciation produced by global cooling has long been proposed to have been a trigger for the Frasnian/Famennian extinctions (Caputo and Crowell 1985, Caputo 1985, Streel et al. 2000a, 2000b, Isaacson et al. 2008). However, decades of searching have failed to uncover sedimentary evidence for glaciation in late Frasnian strata on the landmass of Gondwana (in South America and Africa). In this paper I will argue that this is to be expected, and that the continent of Gondwana is the wrong locality to search for such evidence.