Autumn's chill has many plants preparing to survive the long frigid months of winter. But during the “snowball Earth” events photosynthetic algae had to survive several multimillion year-long global winters.
Between 800 million and 550 million years ago, the Earth froze. Ice and snow covered the Earth two or three times for approximately 10 million years each time.
"Under those frigid conditions, there are not a lot of places where you would expect liquid water and light to occur in the same area, and you need both of those things for photosynthetic algae to survive," said Adam Campbell, a doctoral student at the University of Washington, in a press release.
But fossils of the same algae show up before and after the big chill.
Campbell believes that a long, narrow body of water connected to the ocean could have sheltered the algae, while the rest of the Earth looked like Hoth from The Empire Strikes Back, only without the Wampa ice creatures.
The Red Sea is a good modern example of this type of body of water. The Red Sea is about 6.5 times longer than it is wide, and it connects to the Indian Ocean. A long sea like that during the “snowball Earth” period would have provided enough resistance to glaciers to remain ice-free.
"The initial results have shown pretty well that these kinds of channels could remain relatively free of thick glacial ice during a 'snowball Earth' event," Campbell said.
Another reason Campbell points to the Red Sea as a modern analogue to the ancient algae shelter is that the Sea was formed by continental rifting, a tectonic process known to have been in effect during the “snowball Earth” period.
The research was published in Geophysical Research Letters.
Ice field in the Arctic. (Wikimedia Commons)
No Wampa ice creatures were harmed in making of this blog. (Wikimedia Commons)