Regarding Russ Hopfenberg’s article on population carrying capacity Lawrence Espy and Bill Reese similarly replied to Steve Solmony that the model of population growth limited by the natural carrying capacity of the earth was too general.
Lawrence had pointed out ‘carrying capacity’ has many diverse natural system and artificial system parts, that evolve very differently and those differences need to be considered but were not. Bill similarly pointed out that many ecologists do not see “carrying capacity” as a particularly useful term as the ecosystem (the species’ environment) is constantly changing its ‘productivity’ and is never a fixed target.
All agree with the basic premise that civilization’s whole shaky house of cards will come tumbling down if we are unable to maintain the constant throughput of resources necessary. I offered the following:
Lawrence & Bill,
I think the way to tie the two kinds of potentials, the natural and artificial “carrying capacity” limits of the earth is using the experience curves that indicate our own ability to leverage more and more of those potentials.
That ability to find and invent more cheaper stuff increased for centuries, but is now decreasing, so there was a peak somewhere.
You can’t just talk about it in generalities, as I think Bill’s comment points out, so discussion should not overlook the micro-scale meaning of more general system “capacity” or “responsiveness” concepts, but for the whole earth the experience curves we can now draw seem to tell a dramatic story about when we went past that point of the earth’s peak responsiveness to us.
That point of diminishing returns for a growth curve is the inflection or neutral point (¸¸.o´ ¯), where the second derivative goes from increasing to decreasing, and marks a major transition in the life of any whole system. It locates the point in time when increasing investment in expanding the system begins to result in diminishing opportunity and increasing costs and complications instead.
Before that increasing investment produced multiplying returns of ever greater quality at ever lower cost, throughout the preceding extended history of the growth process.
That’s a profound moment of changing direction, the end of a several hundred year long experience for modern economies, and a key piece of information about when a system should change what it is investing in. It’s a “carrying capacity” metric that is much easier to mathematically define too, and definitive for when a system should reverse its development directions.
It’s also of much more consequence to know of that point when the compound growth of the system ends, it’s “limit of growth” than to know the ultimate asymptote of the same curve which is the whole system “carrying capacity”. The limit of compound growth comes first, is one reason. The main reason is it’s the clear moment of exceeding the earth’s capacity for the system’s growth without coming in conflict with its limits.
I think once people acknowledge the concept we’ll find that all the history curves show it, as with the end of exponential growth in real wages in ~1970 [http://www.synapse9.com/issues/WWatch2009-econ-3.jpg]. There’s also the whole eruption of ever larger and more urgent environmental crises, and lots of other things of that type.
I think the point at which growth actually collided with its limits was really ~1960. Naturally, from what we now know, our economies should have started their turn to self-sufficiency a good bit before then,… but we weren’t conscious.
Phil Henshaw ¸¸¸¸.•´ ¯ `•.¸¸¸¸
NY NY www.synapse9.com
I think the “genetic feedback” theory seems to be just that organisms that destroy their environments don’t prosper, which is true. Still it’s an overstatement to say “It has been demonstrated that” it “is the mechanism by which species achieve ecological balance.” The other main mechanism for achieving balance in systems is for the parts to be responsive, not unresponsive, to each other and to the conflicts that develop as they grow and collide with each other and each other’s interests. That internal responsiveness is demonstrated in how none of our organs normally behave like cancers, for example. So, the default mechanism of achieving balance may be for the parts of an organism to act like cancers and result in death. Internal responsiveness as a way of achieving balance could be seen as the normal mechanism.
True, the former is much the sense of the old neo-Darwinian theory of evolution, where survival is an accident of competitive struggle between systems bent on causing each other’s demise. True also, that the more natural evidence based theory of evolution, employing learning and response by the parts, is slow in being accepted. The more natural theory acknowledges that individuals of all species are observed to actively learn about their environments and that this learning allows them to be responsive to conflict and avoid it, and succeed as a result. You see that active learning in the constant foraging and risk avoidance of most organisms, for example.
Lots of kinds of growth systems, profit seeking mechanisms of a sort, become self-stabilizing by responding to the approach of conflict as being unprofitable, I guess you could say. They “do the math” as it were. Our civilization’s destructive conflict with nature is at the very least “unprofitable” in that sense, and if we were being sensible we’d avoid the growing conflicts rather than blunder along clinging to denials in place of watching the real profit indicators for continuing a futile struggle.
That other growth systems without central controls seem to respond to those signals just fine, is just a mystery of nature as an “most everywhere learning system”. That’s the evidence it seems. I think systems without brains manage to learn more easily than we do is the question. They don’t have artificial worlds in their minds to clutter the signals coming from the real world. People tend to think the world is what they know and then go to lengths to ignore how the real and artificial worlds increasingly differ. That’s not being responsive, and it does invite but not necessitate nature’s default solution for achieving balance.
Phil Henshaw ¸¸¸¸.•´ ¯ `•.¸¸¸¸
NY NY www.synapse9.com