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The end-Cretaceous event was catastrophic for terrestrial communities worldwide, yet its long-lasting effect on tropical forests remains largely unknown. We quantified plant extinction and ecological change in tropical forests resulting from the end-Cretaceous event using fossil pollen (>50,000 occurrences) and leaves (>6000 specimens) from localities in Colombia. Late Cretaceous (Maastrichtian) rainforests were characterized by an open canopy and diverse plant–insect interactions. Plant diversity declined by 45% at the Cretaceous–Paleogene boundary and did not recover for ~6 million years. Paleocene forests resembled modern Neotropical rainforests, with a closed canopy and multistratal structure dominated by angiosperms. The end-Cretaceous event triggered a long interval of low plant diversity in the Neotropics and the evolutionary assembly of today’s most diverse terrestrial ecosystem.
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This content will become publicly available on March 14, 2026
Refugium amidst ruins: Unearthing the lost flora that escaped the end-Permian mass extinction
Searching for land refugia becomes imperative for human survival during the hypothetical sixth mass extinction. Studying past comparable crises can offer insights, but there is no fossil evidence of diverse megafloral ecosystems surviving the largest Phanerozoic biodiversity crisis. Here, we investigated palynomorphs, plant, and tetrapod fossils from the Permian-Triassic South Taodonggou Section in Xinjiang, China. Our fossil records, calibrated by a high-resolution age model, reveal the presence of vibrant regional gymnospermous forests and fern fields, while marine organisms experienced mass extinction. This refugial vegetation was crucial for nourishing the substantial influx of surviving animals, thereby establishing a diverse terrestrial ecosystem approximately 75,000 years after the mass extinction. Our findings contradict the widely held belief that restoring terrestrial ecosystem functional diversity to pre-extinction levels would take millions of years. Our research indicates that moderate hydrological fluctuations throughout the crisis sustained this refugium, likely making it one of the sources for the rapid radiation of terrestrial life in the early Mesozoic.
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- Award ID(s):
- 2317598
- PAR ID:
- 10634340
- Editor(s):
- Brinkhuis, Henk
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Science Advances
- Edition / Version:
- 1
- Volume:
- 11
- Issue:
- 11
- ISSN:
- 2375-2548
- Page Range / eLocation ID:
- 1-10
- Subject(s) / Keyword(s):
- Paleobotany Permian China
- Format(s):
- Medium: X Size: 1.7Mb Other: pdf
- Size(s):
- 1.7Mb
- Sponsoring Org:
- National Science Foundation
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