Society of Vertebrate Paleontology meeting. Jaw shows platypus goes way back.
Stokstad
Erik
E
D000818:Animals; D005075:Biological Evolution; D005580:Fossils; D007568:Jaw / Q000033:anatomy & histology*; D009007:Monotremata / Q000033:anatomy & histology / Q000145:classification; D009412:Nerve Fibers; D010987:Platypus / Q000033:anatomy & histology / Q000145:classification; D004442:Tachyglossidae / Q000033:anatomy & histology / Q000145:classification