A few weeks ago I went to a talk by a senior academic about some of the major differences between the American and Australian approaches to ecological research. As she went through the history of the discipline and some of the most influential research from both continents, I realized that I hadn’t actually read most of the papers she was referring to. Some of the names may have been mentioned in my undergraduate courses, and I vaguely remember covering some of the concepts, but we had never been required to actually read any of these classic papers that form the foundation of ecology.
I am in my second year of a PhD, and I feel like I should know this stuff by now! I know some universities have compulsory coursework for graduate students, but the Fenner School thinks coursework is unnecessary and would distract our focus from the research. But how can we be expected to do good research without a thorough understanding of the literature? Perhaps more importantly, it raises the issue of what we want to get out of our 4 years as PhD students. Personally, I want to come out the other side with more than just a thesis – when I finish my PhD I want to be an ecologist, with a wide range of knowledge and skills.
So how important is it for students to read these foundational papers, and when should they read them? Should they be required reading in undergraduate courses, or do we need postgraduate coursework? Maybe supervisors should recommend reading lists for starting PhDs, or should students just be expected to take responsibility for their own education? Well, a few of us have decided to do just that, and started a reading group for Fenner research students, or anyone else who wants an introduction to the field of ecology.
The Foundations of Ecology Reading Group (‘FERG’) meets monthly to discuss an important ecology paper. Each session is run by a different academic, who chooses the paper and facilitates the discussion. It is also a great opportunity for students to get together and discuss each others’ research, and to interact with and learn from academics (a pretty rare occurrence!).
The first meeting of FERG!
Discussion paper: Orians & Milewski (2007) Ecology of Australia: the effects of nutrient-poor soils and intense fires. Biological Reviews, 82(3) 393-423.
Our first session was run by Pat Werner, whose talk inspired us to start the group. Orians and Milewski was one of the papers she referred to in her talk – it’s relatively recent to be a foundational paper, but Pat thought it would give us a good overview of Australian ecology.
The main point made by the authors is that Australia’s flora and fauna display some interesting anomalies compared to the rest of the world that cannot be explained by climate alone, and that many of these anomalies are adaptations to nutrient poverty and intense fires. In short, plants which have plenty of sunlight but limited nutrients will produce an excess of carbohydrate that cannot be converted into plant tissues, but is used by the plant for many other purposes. For example, they produce nectar and other sugary exudates to attract pollinators, use carbohydrate rich compounds to protect their leaves from herbivores, and protect their seeds with woody capsules. Australian animals have also adapted in a variety of ways e.g. slow metabolism, cooperative breeding in birds etc.
I recently read Tim Low’s book ‘Where Song Began’, which uses the nutrient poverty/intense fire theory to explain why Australia has such large and aggressive nectar feeding birds (compared to other continents where nectar feeding birds are usually small and most plants are wind or insect pollinated). The abundance of nectar produced by Australian plants provides a reliable year-round food source, allowing the evolution of large birds that aggressively protect this resource. I found this explanation compelling – one of those things that seems almost obvious now that I’ve read it!
As a group we discussed the assertion that Australia’s herbivory rates are lower than elsewhere due to the low nutrient content of the leaves. This leads to a build-up of biomass, providing fuel for intense fires that effectively replace herbivores as the main consumer. At first this seems to make sense, and provides an explanation for why Australia doesn’t have large herbivores and experiences severe fires. However, I have read other papers that claim Australia has unusually high rates of herbivory for precisely the same reason – low nutrients in the leaves mean that animals need to eat more to get what they need. There also wasn’t really an adequate explanation for the fact that Australia did have large herbivores before the arrival of humans, and there was no discussion of Aboriginal burning practices.
The most surprising thing for me was the claim that Australia has no herbivorous subterranean mammals (explained by the unpredictability in availability of tubers due to fire, episodic rainfall and nutrient poverty). The authors referred specifically to moles, which we certainly don’t have, but we do have several species of digging or burrowing mammals such as bettongs, bilbies and bandicoots that fill a similar niche. Most of these species have extremely reduced ranges if they’re not completely extinct, but they were once widespread and played an important ecological role.
There was a general feeling in the group that the paper contained quite a few oversights and generalizations that didn’t hold up, and occasionally overstated the conclusions. Some of these issues are probably due to the fact that the authors are not from Australia, however being outsiders could have worked in their favour in allowing them to see the bigger picture. (As someone pointed out, Darwin’s theory of evolution was also criticized for overgeneralizing when it was first published!) And to their credit, the paper did discuss several aspects that are not explained by the theory, and suggest ways it could be tested. Despite these shortcomings I thought it was a very impressive paper, and has certainly changed the way I think about Australia’s unique ecology.
I think the first meeting of FERG was a great success (mostly thanks to the organisational skills of Shana, a fellow PhD student). We had a great turnout, including a few students from other schools who also wanted to get a background in ecology. It was interesting to have students from so many different backgrounds discussing the paper – for some it was very relevant to their research, and for others it was a completely new area but everyone seemed to get a lot out of the discussion. At the end we asked all the attendees to fill out a survey to get an idea of what knowledge people already have and what they would like to read in the future, the results of which will be in the next blog post!