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Paleosols represent fossil records of paleolandscape processes, paleobiotic interactions with the land surface, and paleoclimate. Paleosol-based reconstructions have figured prominently in the study of significant changes in global climate and terrestrial life, with one of the more highly studied examples being the end-Permian extinction (EPE). The EPE was once thought to consist of synchronous extinctions in the marine realm and the terrestrial realm, with the latter displaying a lower magnitude extinction of vertebrate, insect, and plant life. However, emerging stratigraphic records, anchored by high-precision U–Pb ages, and compilations of fossil taxa indicate that the terrestrial realm on Gondwana experienced an asynchronous extinction record with the marine realm; and, at the global-scale, possibly the lack of a true mass extinction for plant and vertebrate communities. Moreover, paleosol-based interpretations of the EPE on Gondwana typically focus on one depositional basin and extrapolate those finding to assess the potential for global paleoenvironmental/paleoclimatic change. This review compiles observations of paleosols, sedimentology, stratigraphy, and geochemical data across Gondwana during the Late Permian in order to critically assess these interpretations of global change in the lead up to the EPE.
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A stark future for ocean life
The year 2021 marked the highest temperature and likely the lowest oxygen content for the oceans since human records began ( 1 , 2 ). These changes have put marine species on the front lines of climate change. For example, marine species’ geographical ranges are shifting faster and experiencing more contractions than those of terrestrial species ( 3 , 4 ). However, whether climate change poses an existential threat to ocean life has been less clear. Marine species are often considered to be more resilient to extinction than terrestrial ones, and human-caused global extinctions of marine species have been relatively rare ( 5 ). On page 524 of this issue, Penn and Deutsch ( 6 ) present extensive modeling to reveal that runaway climate change would put ocean life on track for a mass extinction rivaling the worst in Earth’s history. Furthermore, they reveal how keeping global warming below an increase of 2°C compared with preindustrial levels could largely prevent these outcomes.
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- PAR ID:
- 10373845
- Date Published:
- Journal Name:
- Science
- Volume:
- 376
- Issue:
- 6592
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 452 to 453
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/science.abo4259
