The enamel that protects our teeth apparently comes from an ancient creature, originating from the scales of prehistoric fish.
Scientists revealed this new discovery after careful examination and analysis of ancient remains of fish along with the DNA of a myriad of modern day creatures.
Enamel is considered to be the hardest tissue in the human body, composed of calcium, phosphorus and many minerals. It also provides protection for our teeth as we chew food and from pain from encountering very hot and very cold food.
Most creatures have enamel especially mammals, birds, reptiles and even amphibians including ancient lobe finned fish that evolved to walking and living on land.
Primitive fish had similar types of tissue that covered their bodies and some had enamel type substances on the exterior of their bodies and teeth. These hard tissues consist of the same genes that are clustered together in a genome.
Scientists compared the teeth and outer skeletons of different groups and kinds of fish where they determined that the first enamel emerged in fish that possessed skeletons made from bone. Other fish like sharks and rays possess skeletons made from cartilage.
This ancient fish species is called Psarolepis romeri which is found in China dating back to 445 to 420 million years ago. Scientists consider this the oldest known animal species to possess enamel but the enamel was not found in their teeth but only in some parts of their body.
Scientists then examined another prehistoric fish called the Andreolepis hedei that also lived during the same time as the Psarolepsis. They also found enamel on this fish however, they located it on their scales and not in the bones of its skull.
According to paleontologist Qingming Qu from the Uppsala University and the University of Ottawa, enamel in our teeth are normally used for biting or shearing, enamel was originally used as a protective tissue found in living primitive such as gars and bichirs.
With these findings, researchers believe that enamel originated in the scales before it penetrated dermal bones and finally the teeth.
This new study is published the journal Nature.