Check
out this new publication in Geobiology by W.-H. He, G. R. Shi,
R. J. Twitchett, Y. Zhang, K.-X. Zhang, H.-J. Song, M.-L. Yue, S.-B. Wu, H.-T.
Wu, T.-L. Yang, Y.-F. Xiao:
Late Permian marine ecosystem collapse began in
deeper waters: evidence from brachiopod diversity and body size changes
Abstract:
Analysis of
Permian–Triassic brachiopod diversity and body size changes from different
water depths spanning the continental shelf to basinal facies in South China
provides insights into the process of environmental deterioration. Comparison
of the temporal changes of brachiopod diversity between deepwater and
shallow-water facies demonstrates that deepwater brachiopods disappeared
earlier than shallow-water brachiopods. This indicates that high environmental
stress commenced first in deepwater settings and later extended to shallow
waters. This environmental stress is attributed to major volcanic eruptions,
which first led to formation of a stratified ocean and a chemocline in the
outer shelf and deeper water environments, causing the disappearance of deep marine
benthos including brachiopods. The chemocline then rapidly migrated upward and
extended to shallow waters, causing widespread mass extinction of shallow
marine benthos. We predict that the spatial and temporal patterns of earlier
onset of disappearance/extinction and ecological crisis in deeper water
ecosystems will be recorded during other episodes of rapid global warming.
