Tiny Purgatorius fossils in Denver Basin hint at early primate spread southward Phys.orgTiny teeth found in Colorado deepen the debate over primate origins National GeographicDMNS interns and volunteers (IMAGE) EurekAlert!Miniscule fossil discovery reveals fresh clues into the evolution of the earliest-known relative of all primates Taylor & Francis NewsroomTeeth smaller than a fingertip reveal the first primate ancestor ScienceDaily