Tag Archives: mammoth

A Mammoth’s Journey: New isotopic science

In 2017, John McKay elucidated the history of modern science through the lens of the mammoth, or really, the mammoth hunters, in his book* Discovering the Mammoth: A Tale of Giants, Unicorns, Ivory, and the Birth of a New Science. The difference between what (mainly) European thinkers thought about the meaning of mammoth and other megafauna bones in the early days of discovery and what we knew a decade ago is not merely reflective of the accretion of knowledge and understanding of an observed science. It is much more dramatic than that. For example, a theory thought viable in the 189th century (IIRC, it has been a little while since I read McKay’s book) is that mammoths were still extant, and lived underground as fossorial animals, and could not survive contact with open air. Frozen mammoth carcasses would then represent mammoths that got too close to the surface, accidentally breathed, died, and were frozen in place, partly sticking out. Other early thinking on mammoth and other megafauna remains invoked unicorns and other mythical creatures. We have come a long way.

From what we know about elephants in general (including mammoths), individual mammoths also come a long way from birth to death. I hesitate to use the highly misunderstood word nomadic, which for racist reasons tends to invoke randomness and the strange (and non often existent) practice of never returning to the same place more than once other than by accident. But elephants are potentially nomadic, in the sense that they their daily activity range on average is a tiny fraction of their yearly home range in size, or that every now and then they may move a great distance, depending on resources and other factors. In fact, many modern elephant herds are far from nomadic, either because of the availability of resources or because they are trapped in parks. The point is, understanding the way of the elephant, sensu lato, necessitates understanding their patterns of movement across the landscape, and how they access resources on that landscape, and the relationship between where they move or stay and their social behavior, which in turn links to the animal’s development from birth to old age and ultimate entry, for some, into the fossil record.

And that is informed by a study just out, which takes this journey of understanding a good distance from mid 20th century views of mammal ecology, using techniques initially applied in the 1980s and that have come to full maturity: stable isotopes.

There is a handful of elements that get used a lot in biology, and that occur in nature as a number of different stable isotopes. Atoms make up everything, and exist as distinct immutable elements (unstable elements can change, of course, not the topic of conversation here). But many elements have very slightly different versions, which remain stable, and for most purposes, substitute for each other in chemical reactions But not quite. As these items are moved around in biological systems, passed from one molecular surface to another, or hooked up to each other or other elements to make various molecules, or separated from other atoms, during the process of life itself at the finest level, whether or not a given atom is used or ignored is very slightly biased by which version of the element it is. The difference is so small and insignificant that you can create a biological system in which virtually all of the atoms of a given element are of one stable isotope only, and the system works just fine. But if you provide a biological system with two different isotopes of that atom, let it run for a while, you might find that the tiny molecular machines that make up the works of a cell have been biased for or against one or another element, so the biological mass left at the end — some tissue such as bone or muscle — is made out of a biased subset of those isotopes.

Hand an isotope expert a sample of carbon-containing material and they can tell you if it comes from a sea creature or a land creature based on the isotopes. Hand some stuff from sea mud to an isotope expert and they can tell you if the Oxygen in the skeletal remains of the included dead organisms were formed during a glacial period vs. an inter-glacial period. The utter coolness of isotopic research is unsurpassed. Isotopic research is to animal ecology what genetics is to many other aspects of biology.

So, a large number of researches led by (wait for it…) Matthew Wooller, have applied isotopic analysis to the tusk of an individual woolly mammoth (Mammuthus primigenius) to reconstruct where it went from the time it was born to the time it died, and it lived close to 30 years, in Alaska.

There are two parts to this study. One is to look at the values of the isotopes over time to see how the different life stages went, and the second is to use a fancy simulation to estimate where the animal actually went in Alaska. In my view, the first part is a very important and likely stable result that, when added to other similar results from other individuals, will eventually contribute in a major and long lasting way to an understanding of mammoth life history. The second part is very cool but is necessarily more speculative. For example, it requires faith in a particular reconstruction of ecology of the region at the time, which itself is necessarily speculative.

The following graphic shows the isotopic history of this mammoth.

High vs low values for each element reflect the bias between one or another isotope (not the amount of that element in the sample). The meaning of a shift in isotope can be very controversial or more straightforward. The overall squiggliness of the lines reflects a combination of strong seasonal variation and stochastic or multi-year variation in various aspects of ecology. The things to look at in each squiggle are overall amount of variation across time, and shifts that correspond to the major life history stages of the animal, which are indicated in background color of the graph.

Shifts in Nitrogen values can indicated starvation of lack of food (higher values). A decrease on Carbon value can indicate the same thing. Oxygen can indicated climate change, but the life of one mammoth is too short to spot that signal. It can indicate geographical variation. Strontium represents specific habitats and/or geological location, so as those values change, we assume movement across the landscape to different areas.

From the paper:

Data from the first ~10 cm from the tusk tip showed minimal Sr/ 86Sr variation, suggesting that the young mammoth mostly occupied a range in the lower Yukon River basin in interior Alaska. As a juvenile … the mammoth used a larger range spanning some of the lowlands of interior Alaska between the Alaska and Brooks ranges … The mammoth undertook regular north-south movements within this large core area as well as several long-distance movements, sometimes reaching the eastern end of the Brooks Range and the northern Seward Peninsula in the west … These juvenile-age movements probably represent the movements of a herd (16–18).

With increasing maturity, our study mammoth broadened his range. After ~16 years, a distinctive transition occurred involving higher variance in 87Sr/86Sr along with other isotopic changes. This implied change in the animal’s range probably reflects a transition to reproductive maturity accompanied by long-distance travel between interior Alaska and the North Slope of the Brooks Range. These movements were probably in response
to seasonal changes in resource availability.

One result of this paper is to confirm and underscore the importance of long distance travel in a mammoth’s life. This supports the idea that mammoth confined to small areas (including islands) are selected to become smaller over time (the island effect), which scales the animals to their environment. Isolation to smaller areas of suitable habitat may be linked to the eventual extinction of mammoths.


Discovering The Mammoth: The Evolution Of Modern Scientific Thinking

It wasn’t a mammoth, it was a mastodon. But it was still a big hairy elephant featured at the climax-end of the main exhibit hall in the New York State museum. And it was an exhibit to end all exhibits. The New York State Museum, during its heyday, was world class, and the hall of evolution, which seemed old enough to have involved Darwin himself as a consultant, featured the reconstructed skeleton as well as a fur-covered version, of the creature discovered in a kettle only a few miles away. That exhibit, along with a dozen other spectacular exhibits that to my knowledge have not been equaled elsewhere or since, are the reason I became a scientist, and probably helped direct me towards the study of prehistory and archaeology.

It is because of that background to my own thinking that I paid a lot of attention over the years to elephants and elephant evolution. I got to help excavate an African four-tusker one year even though I had to push off my other responsibilities to do so. I’ve studied the pseudo archaeological traces left behind by wild forest elephants in the Congo, and now and then, ate one, which may seem strange but I was living among the Pygmy elephant hunters at the time so it seemed like the thing to do.

Several years ago, I came across John McKay. First, his blog, then I met him in person. He had been writing about Pleistocene megafauna but focusing on mammoths. Over our many years of friendship, I watched as he steadily worked on a book putting together his findings, and finally, Discovering the Mammoth: A Tale of Giants, Unicorns, Ivory, and the Birth of a New Science has been completed and is out and in print now!

I liken the discovery of the Mammoth by western science to the mostly lost to history but critical coral reef debate involving Darwin. Both events shaped how we do science today and at the same time revealed mind-changing features of the natural world. I didn’t know until interviewing John on Ikonokast (check out the podcast!) that he had originally become interested in Mammoth by a somewhat indirect route because of the extinct animal’s role in, let us say, alt-theories about the Earth and its history. But regardless of how John became interested, he discovered a complex and almost inexplicable relationship between what people were thinking, the way they arrived at those thoughts, and reality which led to a centuries-long struggle to understand something that to us, today, is fairly simple but to 19th century scholars was outrageous.

Religion and cultural belief prohibited thinking about extinctions or the evolution of one species into another, while at the same time, these bodies of thought and knowledge provided explanations for ancient mammal remains that were, to our minds today, seemingly unbelievable. It was the process of going from being totally wrong and basing conclusions on a combination of bad information and unsupportable logic, to the state of understanding that mammoths are a different species of elephant that once existed where we find their remains, but that went extinct because of major changes in their habitats and possibly other causes.

And that is only part of the central story John brings to the reader in the engagingly written and carefully researched Discovering the Mammoth.

I tend to divide science books into two categories: those written by writers about science, and those written by scientists. Both categories have their duds and their great books, though the former category almost always lacks a certain depth and breath but often in a way the typical interested reader can’t see. Meanwhile, books in the latter category can easily go off the rails or assume too much, and be a burden to read. John McKay’s book is written by an expert on the field (this book is in lieu of his PhD thesis) who had previously spent years developing his craft of explaining scientific things, so it is well done in that regard. But there is another reason the typical reader of this blog will grok McKay’s Mammoths. John’s passion other than dead woolly elephants is falsehoods. This is an interest we share. John McKay is a Snope of science, especially in certain areas, but better. Unlike Snopes, which is content to find enough chinks in the armor of some myth or another to snarkily discard it, McKay often recognizes the ways in which a falsehood informs, and contains non-trivial truth, while various truths can misinform while at the same time containing insidious or at least interesting falsehoods. It is his thinking about the way people get things wrong, combined with scholarly training in various areas of literature and history, that uniquely allow him to tell this particular important story about the the evolution of modern scientific thought.

I highly recommend Discovering the Mammoth: A Tale of Giants, Unicorns, Ivory, and the Birth of a New Science. Also, consider it as a holiday gift for your favorite smart person, so they can get even smarter.

Discovering the Mammoth: A Tale of Giants, Unicorns, Ivory … by John McKay

Large hairy elephants got me into paleoanthropology, eventually.

Cohoes Mastodon Exhibit in old New York State Museum, Albany, NY.
Cohoes Mastodon Exhibit in old New York State Museum, Albany, NY.
I had a strong interest in science, and it was nurtured and expanded by my frequent visits to the New York State Museum, and there was never a doubt in anyone’s mind, anywhere, that the coolest exhibit at that museum was the Cohoes Mastodon exhibit. Barbarians eventually came along and tore that exhibit down, along with all the other fantastic and traditional museum displays, when they made the new, slick, produced for consumption and not intense engagement with materials knowledge building museum.

My friend John McKay also got into paleo studies as a young child because of a hairy elephant, but in his case, it was diminutive and green, unlike the large hairy Cohoes elephant. But John persevered in the large elephant area, while I went in somewhat different directions (though I did get to help dig up an extinct four tusker in Africa once). Eventually, John became the Go To Guy in all matters Mammoth and related things. John is an historian, so his focus has been the emerging understanding of the past (and present) as western (and other) civilization(s) repeatedly encountered and grappled with the remains of ancient and unbelievable beasts.

The reason I mention any of this at all is because John wrote a book, Discovering the Mammoth: A Tale of Giants, Unicorns, Ivory, and the Birth of a New Science, that is now available for pre-order, and that you must read.

I’ve not seen the book yet, but I’ve read some of the stuff that is going into it. Think Stephen Jay Gould meets Don Prothero. Rich, engagingly written, context-rich, carefully done description and analyses of the afore mentioned process.

This book promises to be an interesting and important, and very readable, exploration of the development of natural history and modern science. I know John, this is what I expect of him, and this is what I’m confident he is going to give us.

The book will be available in hardcover or kindle. Of course, I’ll write a review as soon as I can. The book is slated for publication in June 2017.

There are two species of African elephant

i-4df9f1c3f1b7fb5409a6d1704a0b7ef4-Elephant_SA_Laden_DSC_3664.jpgEveryone knows that there are two kinds of elephants in this world: Asian and African. The Asian is the only one that can be trained and the African ones live in harmony with their environment until hunters come by and shoot them. Scratch a little deeper, and the African bush elephant lives by destroying its environment and moving on to new areas, where it destroys that environment, cycling back to the original region over generational time; Both African and Asian elephants can be trained; and there are three, not two species of elephant in this world: Asian, African Bush, and African Forest. Once again, everything you know is wrong. But you knew that.
Continue reading There are two species of African elephant