Most species have it in some way or another and humans are certainly no exception to this rule, but is enamel really important to humans? A new study in the Journal of Nature claims humans, like fish, couldn’t have survived if it hadn’t been for the protective shield of their skin.
Researchers have set out to study the structure of fish skeletons throughout historic eras. They have thus, discovered that enamel in prehistoric species was somewhat different than its modern substituent. Naturally, its role has shifted from one historic period to another, according to the specific needs of the respective species.
Analyses of prehistoric fish fossils and DNA samples of modern species have revealed that the first marine exemplars to sport enamel were Psarolepis and Andreolepis. Yet, the exemplars of these two species did not keep the mineral in their mouth, but rather wore it on their skin as a protective shield against predators.
Prehistoric fish with bone skeleton presented enamel-based scales on their epidermis. At first, enamel scales were necessary to ward off attackers, but historic comparisons have revealed that enamel gradually shifted from the skin to the mouth of the fish. Moreover, some cartilaginous fish species, like sharks, for instance, have acquired enamel, too.
Scientists think humans had the same evolution, namely, that they have developed enamel teeth after ganoine (a prehistoric form of enamel) shifted from the skin into the mouth. Enamel inducing proteins appeared at first on the skin and then, in the mouth after millions of years of evolution.
But is enamel really important to humans? Scientists all agree on this one: yes. Enamel keeps our teeth protected against milder or rougher factors, against heat or cold. It is a hardened coat made out of potassium, phosphorus, minerals and calcium that makes our teeth indestructible.
Researchers will work to determine the purpose of enamel scales on the skin of the fish. We can assume the scales prevent underwater creatures from getting injured or bitten by larger species. Yet, many more interesting discoveries can be made.
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