This week, we’ve got a special video from our friends
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.