Warming, stress and survival: terrestrial vegetation dynamics during the Toarcian hyperthermal event

Rapid global warming imposes profound stress on terrestrial ecosystems, both past and present, making it essential to understand how ecosystems respond to climate change in deep time. The Toarcian hyperthermal event (~183 Ma) provides a natural case study for investigating these dynamics. Using the Schandelah-1 core from the North German Basin, we conducted teratological analyses of terrestrial vegetation, revealing pronounced morphological variation. Despite transport and preservation biases, the persistence and diversity of malformations indicate widespread reproductive disruption alongside adaptive strategies, including physiological plasticity and microclimatic buffering, probably driven by thermal stress. Multivariate analyses further confirm significant shifts in pollen malformation during peak warming, showing that terrestrial vegetation was simultaneously highly sensitive and resilient. These results provide critical insights into how land plants coped with rapid thermal stress during this interval, offering a deep-time framework for understanding ecosystem responses to past environmental change.