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Much attention has been given to the negative δ13C anomaly nearly coincident with the Permian–Triassic boundary. New data indicate a stepwise decline in δ13C initiating before the Latest Permian extinction event followed by highly variable δ13C values during the remaining Early Triassic. δ13C values appear much less erratic as global metazoan diversity increased in the Middle Triassic. Given the previously unappreciated magnitude of isotopic change and the number of large δ13C excursions that occurred during the Early Triassic, catastrophic mechanisms like methane release/bolide impact become less attractive to explain the Early Triassic carbon isotopic record as a whole. To cite this article: F.A. Corsetti et al., C. R. Palevol 4 (2005).

A post-extinction calcimicrobial cap rock occurs above the giant Permian skeletal carbonate platform exposed in the western Taurus Mountains (southern Turkey). It was formed during the main step of a very rapid and large-scale platform flooding (Earliest Triassic) and has been found also in other Tethyan localities. This calcimicrobial cap rock, 20 to 40 m thick, consists of thrombolitic and stromatolitic build-ups at the base and most oolitic grainstone in the upper part. It was terminated by a sudden input of fine terrigenous sediments. The domal, columnar and conical stromatolites are ‘anachronistic’ deposits as are the abundant botryoidal and fanning aragonite crystal pseudomorphs. This again shows the uniqueness of the Earliest Triassic period and indicates a delayed biotic recovery. To cite this article: A. Baud et al., C. R. Palevol 4 (2005).