When mammoths roamed Vancouver Island: SFU and Royal BC Museum delve into beasts’ history in our region
Mammoths, the massive pre-historic ice age cousins of the modern-day elephant, have always been understood to have inhabited parts of British Columbia, but the question of when has always been a bit woolly.
Now, a new study from Simon Fraser University has given scientists the clearest picture yet when the giant mammals roamed Vancouver Island.
As part of SFU researcher Laura Termes’ PhD and published earlier this month in the Canadian Journal of Earth Sciences, the study examined 32 suspected mammoth samples collected on Vancouver Island. Of those samples, just 16 were deemed suitable for radiocarbon dating.
The youngest sample was found to be around 23,000 years old and the oldest turned out to be beyond the range radiocarbon dating could measure, meaning it was older than 45,000 years.
Prior to the study, only two mammoth remains found on Vancouver Island had ever been dated before. Both lived around 21,000 years ago, so the Termes’ study provides a greater understanding of when the massive mammals lived in the area.
“This is really exciting because it shows that mammoths have lived on Vancouver Island for a long time,” says Termes, a PhD candidate in the Department of Archaeology. “We were expecting similar results [to the two samples previously dated] but what we found were mammoths that were much older. It is fantastic that they could be preserved for that long.”
Termes says having the curatorial support at the Royal BC Museum and the Courtenay and District Museum and Palaeontology Centre allowing access to their collections was invaluable to the study.
“This research highlights the important role of museum collections for understanding how life has evolved and changed in British Columbia’s deep history,” says Victoria Arbour, curator of palentology at the Royal BC Museum. “It’s great to see Woolly’s relatives in the Royal BC Museum’s collections in the spotlight through this research study.”
The UBC ADaPT Facility (which was instrumental in helping determine if samples were indeed mammoths and not whales or other animals) also played an important role in the research, Termes says.
And archaeologists need all the help they can get because while mammoths were enormous, finding intact samples in British Columbia is actually quite rare.
“When we imagine great big giant animals of the last ice age being found, we might have imagined fully articulated and complete skeletons being systematically excavated. But in southern B.C., that simply does not happen,” says Termes. “Instead, we may get an isolated molar that's been tumbled around in the water for a long time, or maybe a piece of a tusk. And these are what everyday people are encountering.”
For example, one sample she examined was a piece of mammoth tooth found by a child in the gravel at a local playground.
“So maybe it’s a dog owner, taking their puppy for a walk on a rainy day, or a gravel pit operator at work,” says Termes, who grew up in Qualicum Beach. “I really like how these magnificent animals are finding their way into people's lives in routine and everyday ways.”
Termes says the study is part of a larger look at megafauna in B.C. and she plans on radiocarbon dating mammoth samples from other parts of the province.
Mammoth fossils in the palaeontology collection at the Royal BC Museum.
Credit
Royal BC Museum
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Journal
Canadian Journal of Earth Sciences
Article Title
Survival of mammoths (Mammuthus sp.) into the Late Pleistocene in Southwestern British Columbia (Vancouver Island), Canada
Researchers unlock life history secrets of Jurassic mammals using X-ray imaging
Using dental growth rings, scientists reveal dramatic differences in growth patterns between ancient and modern mammals
A new study published in Science Advances reveals how early mammals grew and developed during their pivotal Jurassic radiation. Using a technique called synchrotron X-ray tomography to image growth rings in fossilised tooth roots, the researchers were able to estimate lifespans, growth rates, and even the timing of sexual maturity in these ancient creatures.
“This is the first time we've been able to reconstruct the growth patterns of these early mammals in such detail,” said Dr Elis Newham, a Postdoctoral Research Associate at Queen Mary University of London and Alexander von Humboldt research fellow at the University of Bonn, first author of the study. By studying the spacing and texture of these growth rings, we can not only tell how fast they grew at different stages of life, but also make inferences about their metabolism and overall life history.”
The findings challenge previous assumptions about the growth patterns of mammal ancestors and suggestions that these animals may have grown more similarly to modern mammals. Instead, this paper answers the question posed by similar recent studies of early mammal ancestors: “When did the modern mammal life history evolve?”
The researchers found that the first signs of the modern mammal growth pattern (high growth rates in young animals that are arrested at puberty) originated amongst the earliest true mammals around 130 million years ago, in comparison with relatively little change through life in earlier evolving “mammaliaforms”. However, like mammaliaforms, these animals still grew more slowly and lived for much longer than living small mammals like rats and mice, reaching maximum lifespans anywhere between eight to 14 years-of-age. The timing of this growth rate change, alongside changes in the structure of growth rings, indicates when these animals underwent puberty, and potentially when they became sexually mature.
“This data suggests that while living small-bodied mammals are sexually mature within months from birth, the earliest mammals took several years to reach sexual maturity, corroborating recent findings for one of our studied animals, Krusatodon.” Said Dr Pam Gill, co-lead of the study and Scientific Associate at the Natural History Museum London and University of Bristol. We further find here that this long, drawn out life history was common amongst early mammals all the way through the Jurassic.”
“These results suggest that the unique life history traits of mammals, like high metabolic rates and extended parental care, evolved gradually over millions of years,” explains Dr Newham. The Jurassic period appears to be a pivotal time in this evolution.”
The research team used a technique called synchrotron X-ray tomography to image tiny growth rings in fossilized root cementum, the boney tissue attaching teeth to the jaw. These rings are similar to those found in trees, but on a microscopic scale. By counting the rings and analyzing their thickness and texture, the researchers were able to reconstruct the growth patterns and lifespans of these extinct animals.
“This study is a great example of how new technologies are revolutionizing our understanding of the deep past,” says Professor Thomas Martin of the University of Bonn, a senior co-author of the study. By peering into these fossilised teeth, we can gain valuable insights into the lives of creatures that lived millions of years ago.”
Dr Jen Bright, co-author of the study and Zoology programme director at the University of Hull, added “It’s been so exciting to be involved in this project. Putting Jurassic fossils into a particle accelerator (the synchrotron) and reconstructing the past from it sounds like science fiction, but we can actually do it!”.
This study involved participation of members from Queen Mary University of London, The University of Bonn, The Natural History Museum London, the University of Helsinki, the Geological Survey of Finland, the University of Hull, the European Synchrotron Radiation Facility (France), the University of Southampton, the College of Osteopathic Medicine (United States), the University of Bristol, and the University of Edinburgh.
Journal
Science Advances
Article Title
The origins of mammal growth patterns during the Jurassic mammalian radiation
Article Publication Date
7-Aug-2024
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