Paleontologists from Curtin University and elsewhere have studied a three-dimensionally mineralized heart (the oldest ever found), stomach, intestine and liver from Devonian arthrodire placoderms, an extinct class of armored fishes that flourished from 420 to 359 million years ago. The arthrodire placoderm fossil from the Gogo Formation in Australia where the 380-million-year-old mineralized heart was discovered by Trinajstic et al. Image credit:...
