Your Tooth Enamel Might Have Started As Fish Scales

SCIENCE

Your pearly white smile has a fishy origin story. And no, we’re not referring to your overuse of tooth whitening products. Actual fish were involved, millions of years ago. (Popular Science)

How do teeth help identify people’s origins?

Teachers, scroll down for a quick list of key resources in our Teachers Toolkit.

Smile and say “fish”! Photograph by Joel Sartore, National Geographic

Smile and say “fish”!
Photograph by Joel Sartore, National Geographic

Discussion Ideas

 

 

  • So, how did ganoid fish scales become tooth enamel?
    • They didn’t! (Evolution doesn’t work like that.) Research shows that ganoid scales contain enamel matrix proteins and other chemicals linked to enamel development in teeth. So, a better question is: How did proteins get from scales to teeth? Follow the ganoine:
      • Some of the very earliest bony fishes had ganoid scales, but no tooth enamel—their teeth were “naked dentine.”
      • Somewhere along the evolutionary line, some of these ancient fish began to incorporate ganoine/enamel into other hard surfaces of their bodies, eventually … evolving with ganoine/enamel on their actual teeth, a trait that has been passed down the evolutionary line to almost all toothed creatures today, from humans to crocodiles.”

 

TEACHERS TOOLKIT

Popular Science: Your Tooth Enamel Might Have Started As Fish Scales

Nat Geo: Clue to a People’s Origins video

Nat Geo: Limpets Sink Their Teeth In study guide

Nat Geo: Funnel-Web Fangs study guide

Australian Museum: Fish Scales

(extra credit!) Nature: New genomic and fossil data illuminate the origin of enamel

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s