Where are you from and what were you doing before coming to UM?
I am from Sydney, Australia! It is the largest (and most famous) city in all of Australia and is also the capital of the state of New South Wales. Before coming to UM, I spent nine years studying at Macquarie University in northern Sydney, where I completed my undergraduate, Master’s and doctoral degrees. For my undergraduate, I studied Science and majored in Paleobiology. For my Master’s, I shifted focus onto community ecology, where I studied global patterns of energy use among modern bat, bird, and rodent communities. And for my PhD, I switched back to Paleo, and investigated changes in large-mammal community energy use over the past 130,000 years, focusing on how community energy use changed due to the megafaunal extinctions of the last ice age.
What is the focus of your current research at UM?
Extending upon my previous work looking at paleoecological changes in communities through time, my current research at UM is focused on quantifying community changes in western North America during a notable past warming event called the ‘Mid-Miocene Climatic Optimum’ (MMCO) that occurred from around 17 to 14 million years ago. During this time, global temperatures were about 5 to 6 degrees Celsius higher than they are today, thus making this period a valuable case study towards understanding future ecological impacts under current warming scenarios. As part of this work, I am calculating several community-level metrics including biomass, energy use, and species richness, and will analyze how these all changed across the MMCO in both large- and small-mammal fossil assemblages. Furthermore, I will contrast changes that occurred in ‘tectonically-passive’ Plains regions to those in ‘tectonically-active’ Mountainous regions, to see how warming impacted communities across different habitats and geographic regions.
Why should we expect community-level changes during periods of climate change?
Over evolutionary time, particular species become really well-adapted to specific environments and habitats. As a result, each distinct habitat on Earth contains a particular assortment of species that are all adapted to live in that specific environment. As habitats and environmental conditions are ultimately dictated by climatic factors (e.g. temperature, precipitation, seasonality, etc.), any climate changes that occur (such as an increase in temperature) will naturally result in changes to the local environment. Consequently, in order to survive, any species adapted to that environment will also have to change with the changing habitat – in other words, evolve so that it can continue to successfully live in the new habitat – or otherwise face extinction. Thus, ecological communities change as the climate changes as some species adapt to the new environment, while others die out and new species appear to replace them.
What are tectonically active and tectonically passive regions?
“Tectonically-active” regions are those where active mountain building, and/or other processes associated with mountain building, are currently taking place. Western North America is a perfect example of such a region, where mountain building and volcanic processes are occurring as a result of the oceanic Pacific Plate colliding with, and subducting below, the continental North American Plate along the Pacific West Coast. These processes produce rather significant changes in the local landscape and climate over relatively short time periods. As a result, environments, habitats, and communities all tend to change faster in tectonically-active regions. Meanwhile, “tectonically-passive” regions are simply those where active mountain building and its associated processes are not taking place. The Great Plains of North America, located east of the Rocky Mountains, is an example. As such regions are less tectonically-active, changes in both local environments and communities are usually much slower in passive regions compared to active ones.
How were you drawn into paleontology?
I met John Alroy... Okay, more seriously, I have always been absolutely fascinated by the variety and complexity of life on Earth, and learning about how such variety and complexity came to be. Personally, I blame Sir David Attenborough for this predilection, as I utterly devoured his nature documentaries as a kid! Thus, I was naturally drawn into paleontology as it – through studying the fossil record – investigates and answers questions that ultimately lead to a greater understanding of how the life on Earth that we see today (including our own species) came to exist. Indeed, I think the story of the evolutionary history of life on Earth that has been told through paleontological study is truly remarkable! Furthermore, due to its multidisciplinary nature lying at the intersection of many different fields (biology, geology, chemistry, etc.), paleontology takes a far more holistic view of the world than do other fields of study, a defining characteristic that is particularly appealing to a ‘Big History’ fanatic such as myself!
What is the thing you like most about your work?
That ecstatic feeling you get after having spent months working up a dataset consisting of hundreds of samples and containing at least as many species, and then getting even more data for every single one of those species, and then finally putting it all together and analyzing it and getting a cool result! A result that not only perhaps reveals something new, but also tells an interesting story about the past. I also really like getting those results that don’t quite make sense at first, but do so after some critical thinking (for example, why rates of community energy use in Africa are high today, but were relatively low during the last ice age) – those are always invigorating once you figure them out! But speaking more generally, I simply like overcoming challenges. Whether it’s figuring out how to code for a particular analysis, make a cool figure, prepare and present a conference presentation, or get a paper published in an academic journal, this work constantly challenges me. And while, as a result, it can certainly get frustrating at times, the rewarding feeling you get when you overcome these challenges really makes it all worth it!
