Frank B. Golley
Yale, 1998.
It is hard to imagine a better introduction to ecology than this textbook, which is structured in four clusters of concepts: foundation concepts of environment, system and hierarchical organization; land and water systems, e.g. biome, watershed; population and individual, e.g. body size, climate space; interaction between individual and species, e.g. mutualism, predation.
There are many excellent charts, such as for energy distribution in ecosystems, foodwebs, and graphs for population growth, species-area curves, and so on. The systems approach yields perhaps a more insightful perspective than some more familiar romantic views of the environment:
"Even though a popular ecology rule says that everything is connected to everything else, actually loose connectivity means that there are many discontinuities in the hierarchy. Connections between successive levels do not necessarily mean connections across systems within a level. Ecologists find that connectivity in real-world systems is usually less than 20 percent. Discovery of discontinuity is an important step in studying hierarchical systems." (p.21)
I would hazard a couple of quibbles, however. In the chapter on populations, Golley gives an equation for population density, defined as the number of organisms per unit area of habitat:
density = (births + immigration) - (deaths + emigration)
Strictly speaking, this seems to be dimensionally discrepant, since the right-hand side of the equation gives the population at a given time, without mentioning area.
Secondly, a philosophical point: in the introduction he writes,
"Philosophers say that we can't move from the is to the ought. I don't agree. For me it all begins with experience, the first step into the forest, and everything else flows from that." (p.xiii)
Well, of course we may "move", linguistically or psychologically speaking, from any statement we like to any other, but this does not get round Hume's argument that we may not validly deduce an ought-statement from a set of premises which contain only is-statements. This doesn't mean that no ought-statements may reasonably be made, or we would have no ethics, but it does mean that there is a problem with hoping to derive moral principles from factual statements. This is explored by Sober (p.204).
In the conclusion to the book, Golley says more about how we might do more than accumulate knowledge about the ecosphere:
"We need to express our understanding of connectedness by consciously affirming that we are part of environments, connected to them in ways we do not understand, and that we accept a responsibility for being connected to another. A simple statement of the fact of being connected is a first step towards a deeper acknowledgement of one's role and responsibility." (p.232)
This seems reasonable enough, but, presumably because of his own religious bent, Golley redundantly calls this statement a prayer.
© Paul Taylor 2001