Monthly Archives: December 2013

10 Limitations on Progress in Ecology

Ecological science moves along slowly in its mission to understand how the Earth’s populations, communities, and ecosystems operate within the constraints of human impacts on the Biosphere. The question of the day is can we identify the factors currently limiting the rate of progress so that at least in principle we could speed up progress in our science. Here is my list.

1. A shortage of ecologists or more properly jobs for ecologists. In particular a scarcity of government agencies employing ecologists in secure jobs to work on stable, long-term environmental projects that are beyond the scope of university scientists. Many young ecologists of high quality are stalled in positions that are beneath their talents. We are in a situation similar to having highly trained medical doctors being used as hospital janitors. This is a massive failure on many fronts, regional and national, political and scientific. Many governments around the world think economists and lawyers are key while environmental scientists are superfluous.

2. The lack of proper funding from both government, private companies and private individuals. This is typified by the continual downsizing of government scientists working on natural resource problems – fisheries, wildlife, park management – and continuing political interference with scientific objectives. Private companies too often rely on taxpayers to fund their environmental investigations and do not view them as a part of their business model. Private citizens give money to medical research rather than to environmental programs largely based on the belief that of all the life on Earth, only the human component is important.

3. The deficiency of taxonomic expertise to define clearly the species that inhabit the Earth. The estimates vary but perhaps only 10% of the total biota can be given a Latin name and morphological description, leaving out for the moment all the bacteria and viruses. Equate this with having a batch of various shaped coins in your pocket with only a few of them giving the denomination. This problem has been identified for years with little action.

4. Given adequate taxonomy, the lack of adequate natural history data on most of the biota. This activity, so critical for all ecological science, was called “stamp collecting” and thus condemned to the lowest point on the scientific totem pole. The consequence of this is that we try to understand the Earth with data only on butterflies, some birds, and some large mammals.

5. A failure of ecologists to map out the critical questions facing natural populations, communities, and ecosystems on Earth. The roadmap of ecology is littered with wrecks of ideas once pushed to explain nearly everything, and we need a more nuanced map of what is a critical issue. There are a considerable number of fractures within the ecological discipline about what needs to be done, if people and money were available. This fosters the culture of I win = you lose in competition for money and jobs.

6. The confusion of mathematical models with reality. There is a strong disconnect between models and data that persists. Models rapidly proliferate, data are slow to accumulate, so we try to paper over the fragility of our understanding with mathematical wizardry, trying to be like physicists. Connecting model predictions with empirical data studies would go a long way to righting this problem but it is a tall order in a world that confuses the number of publications and h scores with important contributions.

7 The fact that too many ecologists do not adopt the scientific method of investigation, to carry out experiments with multiple alternative hypotheses with clear predictions. Arguments continue endlessly based on words (‘concepts’) that are so vaguely defined as to be meaningless operationally. If you need an example, think ‘stability’ or ‘diversity’. These vague words are then herded into pseudo-hypotheses to doubly confound the confusion over what the critical questions in ecology really are.

8. The need for ecologists to work in stable groups. Serious ecological problems demand expertise in many scientific specialities, and we need better mechanisms to foster and maintain such groups. The assessment of scientists on the basis of individual work is long out of date, the Nobel Prize is an anachronism, and we need strong groups concentrating on important issues for long term studies. At the moment many groups exist to do meta-analyses and fewer to do science.

9. Placing the technological horse in front of the ecological cart. Ecology like many sciences is often led by technology rather than by questions. The current DNA bandwagon is one example, but we should not get so confused to think that that most important questions in ecology are those that use the most technology. Jumping from one technological bandwagon to the next is a good recipe for minimizing progress.

10. The fractionation of ecology into subdisciplines and the assumption that the only important research work has been done since 2000. Aquatic ecologists do not talk to terrestrial ecologists, microbial ecologists live in their own special world, and avian ecologists do not talk to insect ecologists. The result is that the existing literature is too often wasted by investigators who have no idea that question XX has already been answered either in another subdiscipline or in existing literature from 50 years ago.

Not all of these limitations apply to every ecologist, and at best I would view them as a set of guideposts that need to be considered as we move further into the 21st century.

Krebs, C. J. 2006. Ecology after 100 years: progress and pseudo-progress. New Zealand Journal of Ecology 30:3-11.

Majer, J. D. 2012. Critical times: How has ecological research responded over the past 35 years? Austral Ecology 37:149-152.

Sutherland, W. J. et al. 2010. A horizon scan of global conservation issues for 2010. Trends in Ecology & Evolution 25:1-7.

On Biodiversity Science

Biodiversity science features heavily in articles in Science and Nature and it is a good idea to look at the accumulated wisdom to date. We can begin with the Cardinale et al. (2012) paper in Nature (“Biodiversity Loss and Its Impact on Humanity”) which gives us six consensus statements:

Consensus statement one: There is now unequivocal evidence that biodiversity loss reduces the efficiency by which ecological communities capture biologically essential resources, produce biomass, decompose and recycle biologically essential nutrients.

Consensus statement two: There is mounting evidence that biodiversity increases the stability of ecosystem functions through time.

Consensus statement three: The impact of biodiversity on any single ecosystem process is nonlinear and saturating, such that change accelerates as biodiversity loss increases.

Consensus statement four: Diverse communities are more productive because they contain key species that have a large influence on productivity, and differences in functional traits among organisms increase total resource capture.

Consensus statement five: Loss of diversity across trophic levels has the potential to influence ecosystem functions even more strongly than diversity loss within trophic levels.

Consensus statement six: Functional traits of organisms have large impacts on the magnitude of ecosystem functions, which give rise to a wide range of plausible impacts of extinction on ecosystem function.

followed by four emerging trends:

Emerging trend one: The impacts of diversity loss on ecological processes might be sufficiently large to rival the impacts of many other global drivers of environmental change.

Emerging trend two: Diversity effects grow stronger with time, and may increase at larger spatial scales.

Emerging trend three: Maintaining multiple ecosystem processes at multiple places and time requires higher levels of biodiversity than does a single process at a single place and time.

Emerging trend four: The ecological consequences of biodiversity loss can be predicted from evolutionary history.

I encourage you to read this paper and consider how well it describes a blueprint of past and future research on biodiversity. Here I offer a few thoughts on why I think it consists of a set of worrisome generalizations.

First of all every biologist would like to think that biodiversity is important. But we should consider what the equivalent statement might be for chemistry – chemicals are important. Surely this is both true and of little use, since we can never define scientifically the word ‘important’. Biodiversity is so broadly defined as to be a rather poor noun to use in scientific statements unless it is strictly defined. But you can take any kind of biodiversity measure – species number (richness) for example, and you might find that species X is a terrible weed that is not desirable for farmers but is beautiful in your home garden or useful food for butterflies. Malaria-carrying mosquitoes are not particularly desirable members of the local biological community. But let us all agree that biodiversity is important because it is an ethical belief but not a scientific statement as it stands.

If we look at the consensus statements as scientific hypotheses (I note the word ‘hypothesis’ appears only once in this article), we can ask how you could test them and what the alternative hypotheses would be. For consensus 1 for example, what would be the result of finding a community that increased productivity if certain species were lost from the system? This finding would not be viewed as contrary to consensus one because it would be said that the increased productivity was not done efficiently. It is probably best to assume these statements are not hypotheses to be tested.

As we work our way through the consensus statements, we find they are filled with weasel words that are useful in eliminating contrary evidence. Thus for consensus statement 2 we can stop at biodiversity (many definitions) and then stability (perhaps 70 different metrics) and finally ecosystem functions (of which there are many) and time (weeks?, years?, centuries?). The consensus which sounds so solid is empirically rather empty as any guide to the world.

I am left with many questions. Could not all of these consensus statements have been written 30 years ago? All of them have contrary instances that could be given from the literature, if the terms were rigorously defined. But this many not matter. Let us concede that these generalizations may be right 90% of the time. The bottom line is that we should conserve biodiversity. But this is what everybody has been saying for decades so we are no farther ahead.

The singular problem that concerns me the most is that these kinds of consensus statements are of little use to the land manager or the wildlife manager or the politician who has to make applied decisions at the local level. If we wish to arrest the decline of a particular songbird, what is the utility of these kind of statements? I have concluded that these kinds of papers about biodiversity are a kind of pablum for conservation ecologists to show that Nature and Science really are concerned about conservation issues while at the same time they devote 97% of their issues to the technological fixes that will ‘solve’ all the problems conservation biologists continually point out. As such these kinds of papers are useful statements for political ecology.

The four emerging trends are themselves worthy of another blog. They are vague ideas expressing beliefs that cannot be considered scientific hypotheses without rigorous definitions, and in their present form are almost quasi-religious statements of belief. How they might ever be tested is unclear. I particularly enjoyed the fourth emerging trend since I think that one of the evolutionary laws is that evolutionary history is exactly that – history – not a predictive map of future changes. There is a certain irony of our time that some of the world’s most prestigious evolutionary biologists are anti-religion while biodiversity scientists are trying hard to set up a new religion of biodiversity beliefs.

Cardinale, B. al. 2012. Biodiversity loss and its impact on humanity. Nature 486:59-67.