Controls on body size during the Late Permian mass extinction event

Abstract

This study examines the morphological responses of Late Permian brachiopods to environmental changes. Quantitative analysis of body size data from Permian-Triassic brachiopods has demonstrated significant, directional changes in body size before, during and after the Late Permian mass extinction event. Brachiopod size significantly reduced before and during the extinction interval, increased for a short time in more extinction-resistant taxa in the latter stages of extinction and then dramatically reduced again across the Permian/Triassic boundary. Relative abundances of trace elements and acritarchs demonstrate that the body size reductions which happened before, during and after extinction were driven by primary productivity collapse, whereas declining oxygen levels had less effect. An episode of size increase in two of the more extinction-resistant brachiopod species is unrelated to environmental change and possibly was the result of reduced interspecific competition for resources following the extinction of competitors. Based on the results of this study, predictions can be made for the possible responses of modern benthos to present-day environmental changes.

The evolutionary consequences of oxygenic photosynthesis: a body size perspective

“…Other studies have not addressed this issue statistically. Moreover, it remains unclear whether oxygen stress was more important than other coeval environmental and ecological factors such as reduced predation pressure (Payne 2005) or decreased primary productivity (He et al 2010).…”

Systematics and palaeoecology of Changhsingian (Late Permian) Ambocoeliidae brachiopods from South China and implications for the end-Permian mass extinction

“…Although conodonts are present in one of the studied sections (Rencunping section), they are generally difficult to extract from the siliceous rocks in deep water basinal facies. The ammonoid genera Pseudotirolites and Rotodiscoceras, both index fossils of the late Changhsingian Pseudotirolites-Rotodiscoceras Zone in South China (Yang et al 1987), have been found in the upper part of the Talung Formation in the Majiashan (He et al 2010), Rencunping ), Xinming (in this paper), Duanshan ) and Dongpan sections (Bu et al 2006). In the upper part of the Talung Formation at the Hushan section, we have found the ammonoid genera Pernodoceras, Pleuronodoceras and Pseudotirolites, all index fossils of the Pseudotirolites-Pleuronodoceras Zone, another typical late Changhsingian ammonoid biozone in South China (Zhao et al 1978, He et al 2011).…”

“…To date, few papers on the systematics of deep-water brachiopods have been published (Liao 1979, Zhang et al 1993, Shen & He 1994, Shen & Archbold 2002, He et al 2005, Chen et al 2009). In addition to these systematic studies, several other reports have investigated ecological aspects of these deep-water brachiopod faunas (Chen et al 2006, He et al 2007a, 2010. During the last eight years, the present authors have explored and studied Changhsingian brachiopods from over 10 deep-water sections of South China, including the Hushan section in Nanjing, Majiashan and Pingdingshan sections in Chaohu (Anhui), Rencunping section in Sangzhi (Hunan), Dengcaoba and Xiejiaping sections in Wufeng (Hubei), Xinming section in Anshun (Guizhou), Duanshan section in Huishui (Guizhou), Shaiwa section in Ziyun (Guizhou), Shangname section in Tiane (Guangxi), and Dongpan and Paibi sections in Fusui (Guangxi; Fig.…”

Recovery pattern of brachiopods after the Permian–Triassic crisis in South China

“…A recent study shows that this quick switch happened during the second pulse of the P-Tr extinction (Song et al, 2013). The mass extinction of brachiopods has received widespread attention including studies of extinction processes based on compiled fossil data (Shen and Shi, 1996;Shi and Shen, 2000;Shen and Shi, 2002;Rong and Shen, 2002;Sun and Shen, 2004;Chen et al, 2005a;Shen et al, 2006;Ruban, 2010Ruban, , 2012Chen et al, 2011) and highresolution sampling of fossils (Shen and Jin, 1999;He et al, 2005He et al, , 2007He et al, , 2010He et al, , 2014aChen et al, 2006a,b). However, the recovery of brachiopods in the aftermath of the extinction event has attracted far less attention (Chen et al, 2005b;Posenato et al, 2014;Zakharov and Popov, 2014).…”