Lifetime mobility of an Arctic woolly mammoth

Abstract

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.

Silver Linings at the Dawn of a “Golden Age”

“…The benefit of multi-isotope research is not new, but researchers are only beginning to combine multiple isotopes in isoscape mapping and spatial assignments (see Bataille et al, 2021 for an example and discussion). Depending on what underpins spatial variability in other isotope systems (e.g., geology, anthropogenic emissions, and coastal proximity for sulfur, or climate and topography for oxygen or hydrogen), multi-isotope approaches can reinforce (or alternatively, challenge) inferences made from strontium isotopes alone (e.g., Leach et al, 2009;Crowley et al, in press;Czére et al, in press;Neil et al, 2020;Colleter et al, 2021;Funck et al, 2021;Reich et al, 2021;Wooller et al, 2021). Trace element studies, such as those using lead, can also provide more nuanced insights (e.g., Shaw et al, 2016;Moore et al, 2020;Walser et al, 2020).…”

“…In paleoecology, aDNA often provides a "broad brush" biogeographic context that can form the basis for testable hypotheses of faunal and human movement using 1 https://www.leverhulme.ac.uk/research-project-grants/pleistoherd-integrativeapproaches-late-pleistocene-herbivore-ecology strontium isotopes (e.g., Funck et al, 2020;Vershinina et al, 2021). Genetic data can also provide important information about individual samples, such as sex, which may be highly relevant to movement studies (e.g., Wooller et al, 2021). In archaeology, isotope and aDNA analyses can be combined to approach ancestry in a more holistic sense, particularly when material cultural, funereal, or other archaeological evidence is taken into account.…”

“…Laser ablation technology is continuing to advance and is now becoming more readily available to investigators. The same approaches can be used to analyze larger specimens, including teeth or tusks, provided potential interferences from other elements are taken into account and strontium concentrations are adequately high (Irrgeher et al, 2016;Wooller et al, 2021). Both archaeology and paleoecology will also benefit from (but also have great potential to contribute to) developments in forensic science and food source authentication, as these fields, too, seek to better understand strontium isotope systematics for geographic tracing and provenance studies (e.g., Almeida and Vasconcelos, 2001;Coelho et al, 2017;Techer et al, 2017;Bartelink and Chesson, 2019).…”

Comparison of bulk and sequential sampling methodologies on mammoth tooth enamel and their implications in paleoenvironmental reconstructions

“…To address this issue, a "sequential" approach has also been applied to mammoth and isotope research in some studies (Koch et al, 1989;Fisher and Fox, 2007;Metcalfe and Longstaffe, 2012;Widga et al, 2021;Wooller et al, 2021). Like most mammal species, mammoth tooth enamel has a dominant growth direction from the occlusal surface to the roots at a relatively constant rate (Metcalfe and Longstaffe, 2012).…”

“…Therefore, it has the potential to yield highly resolved time series of paleoenvironmental information over the course of tooth formation. In several recent studies, multiple sequential samples were drilled from the same mammoth tooth following its growth direction with a resolution up to 1mm per sample, forming a time series of isotopic oscillations that likely reflects paleoenvironmental changes at sub-annual scales (Metcalfe and Longstaffe, 2012;Wooller et al, 2021;Miller et al, 2022). The mean value of the sequential samples should therefore reflect the averaged isotopic signal during the period of time of tooth growth, which is also what the bulk sample is expected to represent.…”