New Delhi, Nov. 8 -- Scientists studying a dinosaur bone from Brazil say they have identified chemical evidence associated with blood inside microscopic structures resembling red blood cells, offering a possible glimpse of biology preserved for about 115 million years.

The finding concerns mineralised structures and chemical residues, not liquid blood or intact tissue. An international team led by Curtin University geochemist Kliti Grice examined limb bones belonging to Aratasaurus museunacionali, a meat-eating dinosaur from the Early Cretaceous period.

The research, published on November 2 in the Proceedings of the National Academy of Sciences, reports heme-derived compounds alongside cell-like structures inside the fossil's vascular c...