Teachers' notes - Professor Hugh Possingham, mathematical ecologist

Professor Hugh Possingham

Contents

View Professor Hugh Possingham's photo gallery
You can order the DVD from the Academy for $15 (including GST and postage)


Introduction

Professor Hugh Possingham was interviewed in 2002 for the Interviews with Australian scientists series. By viewing the interviews in this series, or reading the transcripts and extracts, your students can begin to appreciate Australia's contribution to the growth of scientific knowledge.

The following summary of Possingham’s career sets the context for the extract chosen for these teachers notes. The extract covers how he is using mathematics to model ecological systems. Use the focus questions that accompany the extract to promote discussion among your students.

Summary of career

Hugh Possingham was born in 1962 in Adelaide. He received a BSc (Hons) in applied mathematics from the University of Adelaide in 1983. As a Rhodes Scholar he completed a DPhil at Oxford University in 1987 on ‘A model of resource renewal and depletion'. During 1987-88 he was a postdoctoral research associate in biological sciences at Stanford University.

Possingham returned to Australia in 1989 where he was appointed as a postdoctoral research fellow in the Ecosystem Dynamics Group at the Australian National University and as a visiting fellow in Biological Sciences at the University of New South Wales.

From 1991 to 1999 Possingham was at the University of Adelaide. During this time his research into the use of mathematical and computational tools to gain a deeper understanding of ecological systems was recognised by the awarding of the 1999 Eureka Prize for Environmental Research (for work with Dr David Lindenmayer) and the Australian Academy of Science's inaugural Fenner Medal in 2000.

In July 2000 he took up a joint appointment between the Departments of Zoology and Entomology, and Mathematics at the University of Queensland. In February 2001 the Ecology Centre was established at the University and he became its Foundation Director. His research focus is to put environmental problems on a sound mathematical basis. Some of his most recent work involves the design of marine parks, conserving and restoring koala populations in fragmented landscapes, and modelling the spatial and temporal dynamics of kangaroo populations. In 2001 he received the Australian Mathematics Society Medal for distinguished research in the mathematical sciences.

Possingham's expertise has made him highly sought after as a conservation spokesperson and a consultant to government on ecological planning issues. A skilled naturalist, he plays an active role in the work of voluntary naturalist and conservation societies.

Back to top


Extract from interview

Modelling for a desirable future

Tell us about your interest in marine park design.

We were looking at terrestrial landscapes but then we found, most intriguingly, that those same models and algorithms, solution methods, can be applied very well in the marine sector. Marine park design is booming all around the world. All the countries of the planet seem to be wanting a marine park system. And Australia is in there: the Great Barrier Reef Marine Park Authority is using our software to work out how to efficiently redesign the entire marine park, to take it up from the 5 per cent that is conserved at the moment. Also, the Nature Conservancy, as the second biggest non-government conservation organisation in the world, uses our software for all its eco-regional planning.

On land, for several years we have been trying to work out what is a viable population. This is work that I started a long time ago with David Lindenmayer on the viability of Leadbeater’s possum, a small endangered marsupial in the mountain ash forests of Victoria. We make computer models of the dynamics of the population, putting in fire, logging, and the birth, movement and death of the possums, and simulate different scenarios of forest management to work out what scenario will ultimately deliver a population of possums that can persist into the future. We’ve adapted the technologies and now we’ve got more exciting computer graphics, using geographic information systems – basically, coloured maps in a machine.

With support from the Australian Koala Foundation we (Jonathan Rhoes and Clive McAlpine) are applying these ideas to koalas. We can ask how Port Stephens Shire in New South Wales or Noosa Shire in Queensland, say, can have a development plan that allows some development in the shire, so people can build houses and still conserve koala habitat. You’re not going to be able to conserve it all. What are the critical patches? Are there certain sizes of patch that are essential? For example, are little patches useless, so you may as well get rid of them? Is any patch below 100 hectares useless? If so, you need to concentrate your efforts to conserve big patches. How important are corridors between patches? We know roads can increase koala mortality. Where can somebody put in a road, or widen one, with least impact on the koala population? We hope to deliver planning tools to the local and State governments to help them decide how they can most efficiently have koalas in 100 years’ time.

The attractions of converting ecology to an applied science

What is it about this kind of work that keeps you motivated and interested?

I suppose it would be the combination of science with trying to solve real problems. A lot of ecology involves pure ecologists asking fairly theoretical questions about the world, such as why crimson rosellas are so red, or how they have evolved or why their numbers fluctuate so much. These are interesting questions and we need fundamental science, but it doesn’t actually allow you to solve any problems. If crimson rosellas weren’t doing as well as they are, knowing they are red would not mean we could save them. Such knowledge doesn’t tell you exactly what to do to conserve them – nor how to conserve and manage functioning landscapes and ecosystems.

To turn ecology into theoretical applied ecology we need to put a mathematical, decision-theory layer over it. To manage populations and ecosystems we need to be able to predict the future. To predict the future we need models. To be able to manage a landscape or a population of a threatened species such as kangaroos you need to be able to say, ‘If we do this, that will happen to the population. If we do that, the population is likely to do something else.’ You can use the model to predict the future and therefore choose the best management decision to help you get to the future you want.

What I find motivating is that adding the modelling, the predicting, on top of the basic ecological science enables you to make management decisions and so to make the world a better place. Hopefully, in 100 years’ time, at the end of this century, we will still be able to see koalas in Noosa Shire and Leadbeater’s possum in Victoria’s mountain ash forests. If we can’t, then I suppose we will have failed.

Focus questions

  • If you were trying to model how an animal population changes over time, what information would be useful to make your model as realistic as possible?
  • How does ‘ecology’ differ from ‘applied theoretical ecology’?

Back to top


Activities

Select activities that are most appropriate for your lesson plan or add your own. You can also encourage students to identify key issues in the preceding extract and devise their own questions or topics for discussion.

  • Exploring data (Education Queensland)
    This website contains curriculum support materials for teachers introducing students to statistics and the handling of data. It has lots of information, lesson plans, activities and assessment items. Although the material is not specifically aimed at ecological applications it teaches students to look at any type of data in meaningful ways.
  • Australasian Data and Story Library (OzDASL)
    This is a library of data sets and their associated stories. It is intended as a resource for teachers of statistics in Australia and New Zealand. Students can use data sets showing the growth of Tammar wallabies and the frequency of Kiama Blowhole eruptions to look for mathematical patterns or relationships. Alternatively, ask students to take original observations in their own environment and explore their data for mathematical patterns.
  • Population growth and balance (Arcytech, USA)
    In this multidisciplinary lesson students learn about and use a computer model to conduct simulation population dynamics experiments. It is based on system of squirrel/oak tree/hawk, but the principles are applicable to other scenarios.
  • Urbanization effects on streams (Quantitative Environmental Learning Project, Seattle Central, USA)
    In this lesson students work with a data set that looks at the effect of urbanisation on the biological health of streams in the Puget Sound area of Washington State. Students use the data to address a number of questions. After this lesson, students could sample nearby watersheds and look at the same issues in the context of their own environment.
  • Illuminations (National Council of Teachers of Mathematics, USA)
    • Students as researchers: an inclined plane activity
      This is a lesson plan for a multiple-day activity in which lower secondary students learn how to apply mathematics to a real-life setting. Students identify variables, try to make inferences about the relationships among the variables, determine which variables are important and can be measured, and then collect and interpret data.

Back to top


Keywords

  • conservation
  • development
  • ecology
  • mathematics
  • model

Back to top

© 2024 Australian Academy of Science

Top