Greetings, Scientopiads!
I am honored and excited to begin my two-week stint as a guest blogger for one of my favorite science blogging communities. I'm a community paleoecologist and a conservation biogeographer, which means that I'm interested in using the tools of space and time to figure out what ecological questions are most important to understanding how ecosystems, and especially plants, respond to global change-- particularly when facing interacting threats like extinction and climate change. To do this, I spend a lot of time (in my head at least) in the Quaternary, the geologic period that encompasses the last 2.5-ish million years of Earth history. This is a really fascinating natural laboratory, particularly if you zoom in on the last ice age in North American (which is my specialty). Humans show up for the first time, lots of very large animals (like mammoths, giant ground sloths, and beaver the size of black bears) go extinct, and a 2-mile thick ice sheet makes life very interesting for animal and plants. One of my main research interests is in the interactions between animals and plants, which is a topic that hasn't received a lot of attention for reasons I'll get into later. For this reason, I'd like to spend my two weeks at Scientopia detailing the many ways that animals (especially large ones) influence plant species and communities, from the coevolution of tasty fruits to the modern-day dispersal of invasive species. Topics will include bison wallows, avocados and other seeds with Megafaunal Dispersal Syndrome (a tasty, tasty syndrome!), passenger pigeons, sheep spit, and, of course, mammoth poop.
As for me, I recently completed my dissertation at the University of Wisconsin, where I researched the effects of the extinction of ice-age herbivores like mastodons on eastern North American plant communities and fire regimes (more on this-- stay tuned!). I'm currently a postdoctoral researcher at the Environmental Change Initiative at Brown University, where I'm spending a lot of time these days thinking about ecological anachronisms and how well large-fruited trees will be able to cope with climate change. I'm normally found blogging at The Contemplative Mammoth, and on Twitter as @JacquelynGill. Feel free to suggest a topic you'd like to read about in the next two weeks! While my tenure at Scientopia will be a mere blip in the paleoecological record (my timescales rarely involve centuries or decades, let alone years or weeks!) I'm very excited to share my perspective from the fourth dimension--time-- with you.


[...] You can read my introductory post here: Mammoths, acacia, and breadfruit, oh my! [...]
Yay! Welcome, I'm psyched to learn all about this fourth dimension
So did humans extinguish mammoths?
This has been a classic question, and the source of extensive (often heated) debate, particularly when it comes to North America (and Australia for other megafauna). I think that, in North America especially, there is ample evidence that humans contributed significantly to the extinction-- it's simply too coincidental (humans show up, animals that survived >11 previous interglacial-glacial cycles go extinct). However, there is some evidence from ancient DNA and models of habitat availability that changes in available habitat and resources may have stressed some species of megafauna and contributed to a population bottleneck. A lot of this work has been based on the fact that vegetation changed during the population collapse, inferring that the vegetation change caused the extinction. Some of my work suggests it was the other way around-- that the extinction of the mammoths triggered widespread vegetation change. Ultimately, I think the "right" answer may be the most complex-- that a combination of human activity and climate change caused the extinction. Gee, doesn't that sound familiar?
Good to have you here! I want to see BREADFRUITS!!!
[...] Woohoo! @JacquelynGill gets a bigger megaphone on the @ScientopiaBlogs guest blog http://scientopia.org/blogs/guestblog/2012/09/17/mammoths-acacias-and-breadfruit-oh-my/ [...]