From about
1550 to 1850, a global cold snap called the Little Ice Age supersized glaciers
throughout the Arctic. On Canada's Ellesmere Island, Teardrop Glacier extended
its frozen tongue across the landscape and swallowed a small tuft of moss.
Since 1850,
the plant lay frozen under a 100-foot-thick slab of ice as humans discovered
antibiotics, visited the moon and burned 2 trillion tons of fossil fuels.
Thanks to
this latest exploit, evolutionary biologist Catherine La Farge arrived
centuries later at Teardrop's melting edge to find the tuft of the species
Aulacomnium turgidum finally free from its icy entombment. The moss was faded
and torn but sported a verdant hue - a possible sign of life.
Climate
change stories often highlight the teetering fragility of Earth's ecological
system. The picture grew even more dire when a United Nations report said that
1 million of our planet's plant and animal species face the specter of
extinction.
But for a
few exceptional species, thawing ice caps and permafrost are starting to reveal
another narrative - one of astonishing biological resilience.
Researchers
in a warming Arctic are discovering organisms, frozen and presumed dead for
millennia, that can bear life anew. These ice age zombies range from simple
bacteria to multicellular animals, and their endurance is prompting scientists
to revise their understanding of what it means to survive.
"You
wouldn't assume that anything buried for hundreds of years would be
viable," said La Farge, who researches mosses at the University of
Alberta.
In 2009, her
team was scouring Teardrop's margin to collect blackened plant matter spit out
by the shrinking glacier. Their goal was to document the vegetation that long
ago formed the base of the island's ecosystem.
"The
material had always been considered dead. But by seeing green tissue, "I
thought, 'Well, that's pretty unusual'," La Farge said about the
centuries-old moss tufts she found.
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