See the world’s oldest fossilized ‘butthole’ imprint
<p>Fossils show exceptionally rare evidence of a cloacal vent&mdash;the slit that most vertebrates use to excrete, have sex and lay egg&mdash;which could shed light on the evolution of the orifice</p>
- Published
- Mar 4, 2026, 11:30 AM
- Source
- Scientific American