Researchers in Brazil have discovered the first fossilised heart in a prehistoric animal. The preserved 3D heart was found in a 113-119 million-year-old fish called Rhacolepis.. The finding could provide information about early cardiac evolution.

In most cases, an animal’s soft tissue decays quickly after death. Very few examples of soft tissue are found as fossilised remains. The Rhacolepis heart was found in the Santana Formation of Brazil, one of the first sites in which vertebrate fossils were found with evidence of preserved soft tissues.

This research was not funded by the Astrobiology Program, but was undertaken by the University of Sao Paulo Research Unit in Astrobiology, an international partner of the NASA Astrobiology Institute.

The study, “Heart fossilization is possible and informs the evolution of cardiac outflow tract in vertebrates,” was published in the journal eLIFE.