isotope

Giant sea monsters lived in rivers at the end of the dinosaur age

tooth feeding predator Dinosauria Mosasaurus isotope

Giant mosasaurs, once thought to be strictly ocean-dwelling predators, may have spent their final chapter prowling freshwater rivers alongside dinosaurs and crocodiles. A massive tooth found in North Dakota, analyzed using chemical isotope techniques, reveals that some mosasaurs adapted to river systems as seas gradually freshened near the end of the age of dinosaurs. These enormous reptiles, possibly as long as a bus, appear to have hunted near the surface, perhaps even feeding on drowned dinos

15/12/2025 sciencedaily

A strange ancient foot reveals a hidden human cousin

Ethiopia isotope

Researchers have finally assigned a strange 3.4-million-year-old foot to Australopithecus deyiremeda, confirming that Lucy’s species wasn’t alone in ancient Ethiopia. This hominin had an opposable big toe for climbing but still walked upright in a distinct style. Isotope tests show it ate different foods from A. afarensis, revealing clear ecological separation. These insights help explain how multiple early human species co-existed without wiping each other out.

28/11/2025 sciencedaily-human-evo