at the American Association of Chemistry Teachers,

Featuring Sam Kean, the best selling author

behind The Disappearing Spoon.

Enjoy!

While science has done wonders

in solving mysteries about the world,

sometimes people twist those discoveries

into outlandish conclusions.

Instead of using evidence to prove a point,

people who believe in what’s called

pathological science use ambiguity as evidence

claiming that scientists don’t know everything,

and therefore there’s room for my pet theory, too.

That’s exactly what happened

with manganese and the megalodon.

In 1873 a research vessel called the HMS Challenger

set out from England to explore the pacific ocean

and pulled in tons of rocks, some shaped

like mineralized ice cream cones.

They were made of manganese.

When the crew cracked open the cones

they revealed the biggest, most pituitarily

freakish five-inch shark teeth they’d ever seen.

These teeth were later discovered by

paleontologists to belong to the long extinct,

fifty-foot long, fifty-ton megalodon.

All fine science so far.

The pathology started with the man- ganese.

It’s not clear why manganese galvanizes shark

teeth—that is, why thin layers of this metal

deposit themselves on the teeth over time.

But scientists do know how quickly

the metal accumulates, and they deduced that

the teeth date from at least 1.5 million

years ago, meaning the megalodons

probably died out around then.

But some megalodon teeth had a

mysteriously thin manganese plaque,

about eleven thousand years’ worth.

Evolutionarily, that’s an awfully short time.

And really, what’s to say scientists won’t

soon find one from ten thousand years ago?

Or eight thousand years ago? Or later?

In the 1960s, a few enthusiasts with Jurassic Park

imaginations grew convinced that rogue megalodons

still lurk in the oceans.

“megalodon lives!” They cried.

So why do people never see them?

Well, this myth suggested that megalodons

are supposed to be elusive, which gives people

a convenient escape hatch when asked why

the giant sharks are so scarce nowadays.

Unfortunately for big shark dreamers,

the idea crumbles under scrutiny.

Among other things, the teeth with thin

layers of manganese were almost certainly

torn up from old bedrock beneath the ocean

floor and exposed to water only recently.

They’re probably much older

than eleven thousand years.

And although there have been legendary

eyewitness accounts of the beasts,

they’re all from sailors, notorious

storytellers, and the megalodons in their

stories vary manically in size and shape.

Overall, such stories depend on subjective

interpretations, and without objective

evidence, it’s not plausible to conclude

that megalodons, even a few of them,

slipped through evolution’s snares.

The Disappearing Spoon by Sam Kean is

available at fine book stores everywhere.

Want more episodes of The

Disappearing Spoon series?

Head to teachchemistry.org and join the AACT.