Co-authors include scientists from the University of Michigan, University of Alabama, University of Florida, Burke Museum, University of Melbourne, and Vrije Universiteit Brussel, supported by NSF and the David B. Jones Foundation.

The change aligns with the Chicxulub asteroid impact about 66 million years ago, triggering rapid ecosystem shifts rather than changes driven solely by climate or sea-level dynamics.

Overall, the extinction of the dinosaurs appears to have unleashed forest expansion and stabilized river systems, a pattern reflected in a shift from widespread flood-prone deposits to coal swamps and large river-channel sandstones.

A multi-institutional study including Penn State researchers argues that the extinction of dinosaurs reshaped North American landscapes by removing large herbivores that kept ground cover sparse and riverbanks unstable, allowing forests to thrive and river channels to become more contained.

The research further suggests that dinosaurs themselves helped prevent tree and brush growth and destabilize riverbanks, a role that disappeared after their extinction, enabling forests to expand and river systems to stabilize.

The study, which notes a broad, abrupt shift in sedimentology at the Cretaceous–Paleogene boundary, concludes that the mass extinction of dinosaurs triggered a rapid ecological transformation rather than gradual climate or sea-level changes alone.

Contextual note: The material may be time-bound and sourced from Mirage News, with standard caveats about institutional positions.

The research is published in Communications Earth & Environment, highlighting the global extent and abrupt nature of the boundary layer across the planet.

Funding for the research came from the National Science Foundation and the David B. Jones Foundation.

Rock records from multiple sites, including Wyoming’s Bighorn Basin and the Williston Basin, were used to compare pre- and post-boundary conditions and confirm the broad geographic extent of the environmental shift.

Researchers compared Cretaceous–Paleogene boundary records at sites across the western United States and beyond, noting a distinctive iridium-rich layer from the asteroid impact.

Editor’s note mentions that the study builds on earlier coverage and underscores the role of federal research funding in supporting such work.

Geological indicators show a transition from pre-boundary flood-prone silt/mud deposits to post-boundary river-channel sandstones and coal swamps, signaling stabilized rivers and expanding forests.

Pre-boundary rocks depict frequent river flooding and swampy environments, while post-boundary records show more sandstone channels and coal seams, marking a major environmental shift.

Lead co-author Isabel Fendley and colleagues argue that the boundary’s widespread, abrupt sedimentological change supports dinosaur extinction as a driver of rapid ecological transformation.

The research team includes Isabel Fendley (Penn State), Luke Weaver (University of Michigan), and collaborators from Michigan, Alabama, Florida, the Burke Museum, the University of Melbourne, and Vrije Universiteit Brussel, with NSF and the David B. Jones Foundation funding.