A series of fossil footprints was discovered in the Botucatu Formation, in Brazil, revealing the existence of a mammaliaform of exceptional dimensions that coexisted with dinosaurs about 130 million years ago. The footprints, identified as UERJ IC-170 and UERJ IC-171, were described in a new study published last month in the Journal of South American Earth Sciences.
Given their dimensions, this animal would have occupied a very different ecological niche from that traditionally attributed to small Mesozoic mammals, which were generally considered small-scale creatures. The researchers suggest that, in theory, this large-bodied mammaliaform may have been capable of preying on small dinosaurs.
The study represents a significant discovery for paleontology, challenging the common view that mammals from the dinosaur era were exclusively small and marginal in Cretaceous ecosystems.
