Oh, I wish I could keep all me teeth

Sharks’ teeth are constantly replaced throughout life: multiple rows of replacement teeth grow in a groove on the inside of the jaw and steadily move forward as in a “conveyor belt” formed by the skin in which they are anchored. Typically a shark has two to three working rows of teeth with 20 to 30 teeth in each row, although a whale shark has about 300. The rate of tooth replacement varies from once every 8–10 days to several months, some sharks losing 30,000 or more teeth in their lifetime. That’s why the teeth of ancient sharks turn up in abundance in certain strata, and are easy to spot at low tide on some sandy wave-washed beaches. Here, a shark laments such waste.

Oh, I wish I could keep all me teeth;
Now they litter the sea-floor beneath.
I can’t help lamenting
Such a waste of good dentine.
Oh, I wish I could keep all me teeth.

Evolution, it seems, has designed
That we always have gnashers to grind:
So, like soldiers at war,
When one falls, there are more
To replace their lost mate from behind.

But geologists like to find teeth,
So I solemnly hereby bequeath
My discarded enamels
To you beachcombing mammals.
I still wish I could keep all me teeth. . .

(With apologies to the Queen of Poemology, Pam Ayres.)

[Image: eu.usatoday.com]
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