At this time [~60 million years ago], the Earth was a much warmer place and most of the Arctic was in fact a gigantic freshwater lake. Azolla bloomed in the Arctic mega-lake, covering an astonishing area of 1.5 million square miles (4 million sq km), which is roughly half the size of the United States. It is a truly staggering thought. If you were to visit this Azolla-filled lake 60 million years ago, you could fly in an airplane for about three hours overhead and continue to see this one species covering the top of the water like a green blanket. –
“Ferns: Lessons in survival from Earth’s most adaptable plants” (Ch 6)
That one paragraph might fill your “fern stuff” quota for today; indeed, it might be more fern stuff than you ever wanted in all your days. But I’m going to take a chance here and provide some important context: an individual Azolla-fern plant would fit on the fingernail of your little finger. Yet some Azolla plants, working together in a truly impressive collective effort, managed to cover 1.5 million square miles of lake. But hey, it wasn’t for long, right? If you’d blinked, you’d have missed it, right?
Wrong.
The bloom lasted about 1 million years and is known as the “Azolla event”. Scientists have estimated that over 10 trillion tons of CO2 were sequestered during this period, enough to cool the Earth by 9°F (5°C).
That part about this feat being “known as the Azolla event” strikes me two ways.
- First, that seems more than fair. If I did something that extended for 1.5 million square miles for 1 million years (or thereabouts), I would fully expect it to be known as the “Gibson event”. Or maybe The Gibson Event®, hold the scare quotes and order the commemorative mugs. And speaking of fair, if any of you had a similar achievement I would expect it to be named after you. I would even write a letter of support to the Event-Naming Commission.
- Second, known to or by whom, buddy? Not to this one-time student of high-school biology and ongoing student of natural history. I was this many weeks old when I first heard of the Azolla event. I expect the same is true for you.
This is yet another reminder that high-school or even college need not — nay, should not — be the end of our learning. There is a *ton* of cool stuff out there, even leaving aside the ferns.
