Study takes unprecedented peek into life of 17,000-year-old mammoth | uOttawa
A view of the excavation site of the mammoth tusk from north of the Brooks Range in Alaska.
Photo by Pam Groves, University of Alaska Fairbanks
According to creationist superstition, a magic man made of nothing created the entire Universe, Earth, and all life on Earth, out of nothing, using magic words spoken in a language that no-one else spoke, and, using the rotation period of a planet that didn't exist, completed it all in 6 days during what creationists call 'Creation Week'.
7,000 years before that, mammoths were living their daily lives in what is now Alaska, and leaving tusks that carried a daily record of where they were living and consuming vegetation, in the form of 'signature' ratios of isotopes of strontium.
Strontium finds its way into the plants that animals eat from the underlying rocks where the ratio of the different stable isotopes of strontium (87Sr and 86Sr) in it changes very little over millions of years, giving a characteristic 'signature' that can be used to identify where the food plants were growing. This signature strontium was deposited in the growth layers of mammoth tusks, starting at the tip when the mammoth was born, and ending in the root when the mammoth died. In between the two is a complete record of where the mammoth roamed.
But first, scientists need to build a strontium isotope map so they can match up the record in the tusks with the geographical location in which the food grew that day. And this is where voles come in. Voles also eat the strontium-containing grasses that mammoths eat and so build up a record in their teeth. However, voles are mostly very sedentary in their habits so have a very restricted range and because the strontium in the rocks changes little, even present-day voles can be used to build up a strontium isotope map.
Using that knowledge, an international research team led by Clément Bataille, an assistant professor and researcher in the Department of Earth and Environmental Sciences in the Faculty of Science, Ottawa University, Canada have analysed the strontium content of a mammoth tusk found on Alaska’s North Slope above the Arctic Circle, to build up a picture of its daily life and travels.
The study is explained in a press release from Ottawa University:
An international research team has retraced the astonishing lifetime journey of an Arctic woolly mammoth, which covered enough of the Alaska landscape during its 28 years to almost circle the Earth twice.The team's findings are published in Science:
Scientists gathered unprecedented details of its life through analysis of a 17,000-year-old fossil from the University of Alaska Museum of the North. By generating and studying isotopic data in the mammoth’s tusk, they were able to match its movements and diet with isotopic maps of the region.
Few details have been known about the lives and movements of woolly mammoths, and the study offers the first evidence that they traveled vast distances. An outline of the mammoth’s life is detailed in the new issue of the journal Science.
“It’s not clear-cut if it was a seasonal migrator, but it covered some serious ground,” said University of Alaska Fairbanks researcher Matthew Wooller, senior and co-lead author of the paper. “It visited many parts of Alaska at some point during its lifetime, which is pretty amazing when you think about how big that area is.”
“It’s just amazing what we were able to see and do with this data,” said co-lead author Clément Bataille, an assistant professor and researcher in the Department of Earth and Environmental Sciences in the Faculty of Science, who led the modeling effort in collaboration with Amy Willis at the University of Washington.
Researchers at the Alaska Stable Isotope Facility, where Wooller is director, split the 6-foot tusk lengthwise and generated about 400,000 microscopic data points using a laser and other techniques.
The detailed isotope analyses they made are possible because of the way that mammoth tusks grew. Mammoths steadily added new layers on a daily basis throughout their lives. When the tusk was split lengthwise for sampling, these growth bands looked like stacked ice cream cones, offering a chronological record of an entire mammoth’s life.
“From the moment they’re born until the day they die, they’ve got a diary and it’s written in their tusks,” said Pat Druckenmiller, a paleontologist and director of the UA Museum of the North. “Mother Nature doesn’t usually offer up such convenient and life-long records of an individual’s life.”
Scientists knew that the mammoth died on Alaska’s North Slope above the Arctic Circle, where its remains were excavated by a team that included UAF’s Dan Mann and Pam Groves, who are among the co-authors of the study.
Researchers pieced together the mammoth’s journey up to that point by analyzing isotopic signatures in its tusk from the elements strontium and oxygen, which were matched with maps predicting isotope variations across Alaska. Researchers created the maps by analyzing the teeth of hundreds of small rodents from across Alaska held in the museum’s collections. The animals travel relatively small distances during their lifetimes and represent local isotope signals.
Using that local dataset, they mapped isotope variation across Alaska, providing a baseline to trace the mammoth movements. After taking geographic barriers into account and the average distance it traveled each week, researchers used a novel spatial modeling approach to chart the likely routes the animal took during its life.
Ancient DNA preserved in the mammoth’s remains allowed the team to identify it as a male that was related to the last group of its species that lived in mainland Alaska. Those details provided more insight into the animal’s life and behavior, said Beth Shapiro, who led the DNA component of the study.
Strontium and Oxygen isotope maps of Alaska
Split tusk showing growth rings
For example, an abrupt shift in its isotopic signature, ecology and movement at about age 15 probably coincided with the mammoth being kicked out of its herd, mirroring a pattern seen in some modern-day male elephants.
“Knowing that he was male provided a better biological context in which we could interpret the isotopic data,” said Shapiro, a professor at the University of California Santa Cruz and investigator at the Howard Hughes Medical Institute.
Isotopes also offered a clue about what led to the animal’s demise. Nitrogen isotopes spiked during the final winter of its life, a signal that can be a hallmark of starvation in mammals.
Discovering more about the lives of extinct species satisfies more than curiosity, said Wooller, a professor in the UAF College of Fisheries and Ocean and Institute of Northern Engineering. Those details could be surprisingly relevant today as many species adapt their movement patterns and ranges with the shifting climate.
“The Arctic is seeing a lot of changes now, and we can use the past to see how the future may play out for species today and in the future,” Wooller said. “Trying to solve this detective story is an example of how our planet and ecosystems react in the face of environmental change.”
Other institutions contributing to the study included Florida State University, Montanuniversität Leoben, Liaocheng University and the National Park Service.
AbstractAlthough this all happened a mere 7,000 years before creationism’s legendary 'Creation Week', which is a mere tick in geological time compared to the 40,000 years for Neanderthal art, hundreds of millions of years for trilobites, or the billions of years between then and LUCA, it is all part of that rich history of life on Earth the happened in those vast eons of time before creationists imagine Earth was created out of nothing by a magic man made of nothing who existed when nothing was something that existed.
Little is known about woolly mammoth (Mammuthus primigenius) mobility and range. Here we use high temporal resolution sequential analyses of strontium isotope ratios along an entire 1.7-meter-long tusk to reconstruct the movements of an Arctic woolly mammoth that lived 17,100 years ago, during the last ice age. We use an isotope-guided random walk approach to compare the tusk’s strontium and oxygen isotope profiles to isotopic maps. Our modeling reveals patterns of movement across a geographically extensive range during the animal’s ~28-year life span that varied with life stages. Maintenance of this level of mobility by megafaunal species such as mammoth would have been increasingly difficult as the ice age ended and the environment changed at high latitudes.
Matthew J. Wooller et al.
Lifetime mobility of an Arctic woolly mammoth.
Science 373, 806-808 (2021). DOI:10.1126/science.abg1134
© 2021 The Authors, published by American Association for the Advancement of Science. Reprinted with kind permission under licence #5677270719138.
And you can bet your house on there being yet more science papers out shortly, all of which will similarly refute creationism quite incidentally, and not a single one will support such a childish superstition.
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