Researchers have discovered the world's oldest heart in the fossilized body of a 380 million-year-old fish.
According to researchers, the heart has been "beautifully preserved" and it could provide some insight into the evolution of mankind. The soft tissue from remains that are millions of years old is almost never discovered intact so they were surprised to find the fossilized heart preserved and maintaining its 3D shape. The heart had not decayed or been eaten.
The heart was discovered by researchers from Curtin University in Australia in the fossil of the ancient jawed fish. Along with the heart, there was a fossilized stomach, intestine, and liver. This was the first time that researchers could see all the organs together in the primitive jawed fish.
The ancient jawed fish belongs to an extinct class of fishes called arthrodires. The anterior part of the body of the fish was covered by a shield of bony plates.
These fishes flourished in the Devonian Period which lasted anywhere from 419 to 358 million years ago. The fish are considered to be an example of our "earliest jawed ancestors."
The ancient fish has a large liver which enabled it to become buoyant like a shark. The anatomy of the fish is similar to that of the modern shark. The heart that was preserved also had two chambers which were surprising to see in the early fish. This indicates that the heart was more efficient and enabled the fish to become quick predators per the Smithsonian.
The 380 million-year-old fossilized heart had already been discovered in 2008 but it took until now to use modern scanning techniques to study the soft tissues.