A U-Pb zircon age constraint on the oldest-recorded air-breathing land animal Suarez, Stephanie E. ; Brookfield, Michael E. ; Catlos, Elizabeth J. ; Stöckli, Daniel F. Abstract Publication: PLoS ONE Pub Date: June 2017 DOI: 10.1371/journal.pone.0179262 Bibcode: 2017PLoSO..1279262S