Overview
- The PNAS paper, published Monday, November 2, reports detection of heme B and porphyrin-like chemical signals colocated with numerous ellipsoidal microstructures inside vascular canals of an Aratasaurus museunacionali leg bone.
- Researchers used microscopy, mass spectrometry, spectroscopy and elemental mapping to tie iron, carbon and nitrogen signatures to the cell‑like forms and to identify an altered heme derivative in bone extracts.
- The team proposes that rapid burial on a low‑oxygen microbial mat and mineralization by hausmannite, a manganese oxide, plausibly stabilized cellular shapes and small molecules over deep time.
- The study does not recover intact hemoglobin proteins or DNA and authors and external experts warn the structures could reflect microbial activity or modern contamination, so replication across other fossils is the immediate priority.
- If independently confirmed, the methods could open molecular‑level studies of dinosaur physiology and preservation and prompt reanalysis of museum collections while also informing searches for ancient biosignatures beyond Earth.