YSM Issue 97.1
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FEATURE<br />
Paleontology<br />
BY HANWEN ZHANG<br />
ART BY PATRICIA JOSEPH<br />
Tracking an Ancient Woolly Mammoth’s Journey of a Lifetime<br />
For all our Ice Age movies, artistic<br />
renderings, and sci-fi murmurings<br />
of de-extinction, mammoths have<br />
never quite lost their mythic proportions.<br />
The thirteen-foot darlings of every natural<br />
history museum continue to loom with about<br />
as much mystery as majesty. We know that<br />
they roamed the tundra steppes for roughly<br />
290,000 years, during which they grazed on<br />
arctic plants, briefly brushed shoulders with<br />
prehistoric humans, and had their likenesses<br />
transferred onto cave paintings. Then, around<br />
the time humans were building pyramids,<br />
they disappeared. The causes for their<br />
extinction—human hunting, climate change,<br />
or some mix of both—have been hotly debated<br />
as they remain tantalizingly unclear.<br />
Enter Elma, an ancient woolly mammoth,<br />
and one of only two specimens with complete<br />
tusks in all of Alaska. In a study published last<br />
month in Science, Elma is the star as a team<br />
of anthropologists and biologists provides an<br />
intricate reconstruction of her entire lifetime<br />
with the help of isotopic dating technologies.<br />
As just the second mammoth reconstruction<br />
of its kind, it offers an intimate glimpse into<br />
the creature’s habits—and an enticing glance<br />
at what mammoth interactions with early<br />
humans may have looked like.<br />
“We can’t [...] say for sure that humans killed<br />
this mammoth, but we’ve got means and<br />
motive at this point,” said Audrey Rowe,<br />
a PhD candidate at the University of<br />
Alaska and the lead researcher on<br />
the study. Elma<br />
was uncovered at Swan Point, the oldest<br />
archaeological site in Alaska, by researchers<br />
during the early 2000s.<br />
The study’s genetic and isotopic analysis<br />
chronicles an impressive yet punishing<br />
journey through the Alaskan hinterlands that<br />
ends in a cryptic fashion. According to the<br />
study, Elma trekked roughly one thousand<br />
kilometers from southeast Beringia, in<br />
present-day Canada, deep into interior<br />
Alaska in the span of two and a half years.<br />
Then, still at the peak of her life and roughly<br />
twenty years old, she died—right next to an<br />
area of known human settlement.<br />
This cold case has the set-up of a prehistoric<br />
Agatha Christie plot, but there’s no smoking<br />
gun. Elma’s remains were uncovered<br />
alongside another closely related juvenile and<br />
a newborn and were dated from around the<br />
same time humans had started populating<br />
the region. She died in healthy condition, and<br />
her body lacked physical evidence of having<br />
been hunted, unlike mammoth samples in<br />
Siberia or Poland, which feature spear points<br />
lodged in spinal vertebrae or microblades<br />
buried in ribs.<br />
Image Courtesy of Flickr<br />
All signs nonetheless point to death by<br />
humans. “These early people in Alaska also<br />
certainly seem to have the technology [...] to<br />
bring down a mammoth,” said Matthew<br />
Wooller, a University of Alaska professor<br />
of chemical oceanography and an author<br />
of the study. Elma was found in the same<br />
time layer as the remains of the two younger<br />
mammoths, and her path overlaps neatly<br />
with human settlement at a time when<br />
they were capable of developing lethal<br />
stone projectiles—there are simply too<br />
many coincidences.<br />
Researchers were just as lucky to come<br />
across a tusk as uncompromised as hers.<br />
The equivalent of rings on a tree trunk,<br />
mammoth tusks offer telling records of life.<br />
Rowe explained that their tusks—similar to<br />
those of elephants—stack new layers atop<br />
each other as they grow, almost like ice<br />
cream cones. Elma’s tusk unraveled her story<br />
from the tip to her trunk.<br />
Using recently developed isotope analysis<br />
techniques, the researchers were able to chart<br />
Elma’s footsteps across prehistoric Alaska.<br />
They sliced open her tusk, drilled into the<br />
ivory at millimeter-length increments, and<br />
measured the isotopic ratios of strontium,<br />
sulfur, and oxygen—all of whose stable halflives<br />
can be deeply informative. Levels of<br />
strontium-87, an isotope formed in rocks by<br />
decaying rubidium, vary across the world;<br />
what follows is a telltale geographic<br />
signature, since<br />
32 Yale Scientific Magazine March 2024 www.yalescientific.org