YSM Issue 97.1

Paleontology
FEATURE
strontium can vary across mountain ranges or
even just a few valleys. The broad outlines of
Elma’s journey took shape when researchers
paired their isotope measurements with maps
that captured the geographic distribution
of strontium-87 ratios. Once coupled with
oxygen-18 and sulfur-34—which can track
water sources and mean annual temperature,
respectively—the 14,000-year-old picture
became even clearer. What the data sketched
was a trek inland, across highlands and the
more arid swaths of the tundra.
Peripatetic, or nomadic, mammoths
are no strangers to long-distance, crosscontinental
hauls. Wooller explained that
the previous study of this kind—featuring
an 18,000-year-old male—had unearthed
even longer treks that had taken the
mammoth to similar regions in interior
Alaska. Sexual differences were probably at
play: like elephants, male mammoths may
have left their herds at a younger age and
traveled more during their lifetimes.
Roaming some three thousand years
after her male counterpart, this study’s
mammoth offers a more dramatic portrait
of her kind’s sunset, and of an arctic
habitat hardly recognizable from the one
we might imagine today. “A lot of Alaska
was not covered by ice at all,” Wooller said.
The mammoth population would have
peaked some six thousand years before
Elma. The Last Glacial Maximum—the
last moment when glaciers covered nearly
eight percent of the world’s total surface—
had ended, ushering in scrubby forests
that crept onto riverbanks and cropped
up along the steppes.
For a species so used to their barrenly
flat haunts, the dramatic ecological
changes would have fractured habitats
and made them increasingly vulnerable
to predation. The mammoths gravitated
towards the same regions as human
settlements and increasingly crossed
paths with our earliest ancestors. Some
combination of human-driven extinction
and the forces of climate change likely
led to the mammoth’s demise. “I think,
at least in interior Alaska, the answer is
more nuanced than that black or white,”
Rowe said.
Like the mammoth’s shaggy, fiftycentimeter
coat, the details remain
understandably hairy; piecing together
the entire arc of a species calls for a
sample size greater than just two. Wooller
and Rowe both pointed out the need to
analyze more sequences of this kind. In
the interim, research could also take new
directions—Wooller noted that recent
excavations in Canada and Siberia have
detected mammoth DNA in permafrost
layers less than ten thousand years
old, indicating the possibility of latesurviving
groups.
“Now that we’ve got something
more about the mobility
of the animals in this
region, it
would be
great to get at the people as well,” said
Ellery Frahm, a Yale anthropology
professor not involved in the study. Frahm,
whose research focuses on early human
group interactions in Eurasia, explained
that tracking mammoth movements is crucial
to discovering the ways our ancestors engaged
with their food sources.
For the researchers, simply coming face
to face with our mammoth ancestors is
as fulfilling as playing detective. “It’s
more exciting to just be learning about
mammoth behavior because we have so
little knowledge about that right now,”
Rowe said. “Studies like this one are
starting to actually pin down some actual
truths instead of forcing us to make
these assumptions.” Amid the decadeslong
buzz of mammoth DNA extraction
and de-extinction projects, tracing their
stories may well be the truest gesture of
bringing them back to life.
Elma would have been about 13,600
years old by the time “mammoth” entered
the dictionary. It came with Russian
roots, surfacing in the English vocabulary
during the eighteenth century and
coming to signify largeness.
Big. Colossal. Huge. Gigantic,
still fitting today for animals
about which there can never be
too much space for wonder
or questions. ■
Studies like this one are starting
to actually pin down some
actual truths instead of forcing
us to make these assumptions.
www.yalescientific.org
March 2024 Yale Scientific Magazine 33