Never forget the “struggle for existence”

I often think that those who say we face “climate change catastrophe” mustn’t really understand the most basic tenet of evolutionary theory: that life involves a struggle for existence.

Consider, for example, what the Sunday Times television guide says about tonight’s wildlife documentary on BBC2, The Polar Bear Family and Me: “polar bears are the world’s largest carnivores, but global warming is making it more and more difficult for them to find food”.

In fact, individual polar bears have always found it difficult to find food. Whenever less food was available, their numbers fell, as more of them succumbed to various causes of death. Most such causes have always been related to food shortage: diseases of malnutrition, exhaustion through having to travel long distances to find food, attacks by other hungry polar bears, even killing at the hands of human beings they wouldn’t have approached if they hadn’t been so hungry.

Whenever more food was available, their numbers rose – up to the point at which food was difficult to find again. That brings us right back to the situation described in the previous paragraph. Polar bear numbers are not decided by ancient “polar bear wisdom” with which they thoughtfully control their own numbers, nor is there a “delicate balance of nature” in the Arctic that perfectly suits polar bears. The issue is always settled the hard way – by food shortages and by death.

As Arctic ice melts, polar bear numbers may be rising or falling – and no one seems to know with much confidence which. Polar bears are good swimmers, and they get most of their food in the form of other swimming animals such as seals. It might be that more open water has the effect of increasing the availability of food – a situation that sustains larger numbers of polar bears. Or it might be that more open water allows more polar bear competitors into their “turf”, which help to use up the food supply. Or that less ice means fewer air-holes where seals can be caught. These are situations that sustain smaller numbers of polar bears. But fewer bears means fewer competitors for each individual bear, which makes finding food slightly less difficult. Which reverses things a bit. Via many swings and roundabouts of fortune, a sort of balance is struck. It isn’t a balance that arises through design, or anything like it. It’s a balance that results from the “chips falling where they may”.

Whichever way the chips may fall, the difficulty of finding food remains roughly the same. The degree of difficulty is always approximately a matter of life and death.

I’m not sure why so many climate alarmists seem to be unaware of this situation, which exists pretty much everywhere in nature. It might be that their area of specialization has nothing to do with evolution, which makes them no better qualified than any other layperson to guess the effects on life of a changing climate. Or it might be that the insight Darwin credited Malthus for bringing to his attention has been largely forgotten in today’s attitudes to “ecosystems”. These attitudes assume that there is something akin to design in nature, and suffering gets much worse when a supposed “way things were meant to be” is disrupted.

Wherever there’s life, there’s a struggle for existence. Whether sea levels rise or fall, whether ice caps retreat or advance, whether the climate warms or cools, whether the earth is beset by floods or droughts, even if everything stays exactly the same – living things have to battle against each other and their environment as a matter of life and death. There’s a lot of suffering in all that strife, and changes are just as likely to bring a little relief from that vast tapestry of suffering as to make it a little worse.

9 thoughts on “Never forget the “struggle for existence”

  1. Hmmm, but you’re rather missing the point. It’s not that bears are “designed” or there’s some mystical “balance of nature”. It’s purely that polar bears (and many other species) evolved to specialise in a particular environment. If that environment changes slowly, bears (and other species) better adapted to the new environment will survive and hence the species will evolve.

    Rapid changes forego this. One problem with ice melt is that chunks of ice are further apart meaning polar bears have to swim more. This affects their calorie usage. If this ice melt was gradual, one assumes bears who swam more efficiently or burner calories more efficiently or hunted more effectively would evolve. Instead, it looks more plausible they will die out first. It’s rather like a meteorite strike – success in an environment doesn’t protect against a few tons of flaming rock.

    If climate change is happening, then this scenario will happen to multiple species in multiple habitats. Obviously eventually other species will evolve. But we’re talking many thousands of years. In human scales those species (perhaps including ones useful to humanity) will be gone.

  2. Don’t forget everyday movement! The “perfect environment” for any species (if there is one) usually moves north or south, shrinks or grows, etc., relatively slowly as ice sheets, sea levels, etc. change. This movement is much slower than the movement of living things — even of rooted plants spreading into a new area (such as pine forests growing further north). There are some winners and some losers in this sort of change — but on the whole there are bound to be as many of each.

    I don’t think there’s any realistic prospect of any habitat type disappearing altogether, still less of any species being “caught unawares” and becoming extinct. But even if there were such a prospect — what’s the big deal? The “death” of a species is not actual death, and the continuation of a species is not “unending life” for any of the individuals who belong to it. If change is so dramatic as to cause the extinction of an old species, it’s probably dramatic enough to give rise to new species. Any losses and gains here are so abstract as to be incalculable. For example, is the loss of an old species of mollusk worse than the gain of a new species of arthropod? No one can evaluate such things.

    • Re no habitat disappearing, the northern stretches of ice could conceivably be too broken up to support a viable polar bear population. They are evolved for living on ice, so unlikely to outcompete existing bear populations further south.

      The problem with climate change is tipping points, where small changes at critical points lead to rapid alterations. Plausible such changes could happen faster than animals could migrate. You also assume that migration is not prevented by existing deserts, seas etc.

      As for evolution, of course new species could evolve. But evolution generally takes a long time. So in human life scale terms, it’s not going to matter. Extinction events will mean (as after other extinction events) fewer species for some considerable time.

      • I’m one of those people who thinks science needs philosophy. When someone tries to do science without philosophy, all that happens is bad philosophy sneaks in the back door. It seems to me that most current thinking about “climate change catastrophe” is riddled with bad philosophical assumptions about design.

        The assumption that ecosystems are exquisitely brittle – so that any change spells disaster to life – in effect assumes design in biology. The idea that the Earth’s climate can reach a “tipping point” in effect assumes design in geology.

        The idea of a “tipping point” is essentially the idea that the climate is in unstable equilibrium: it’s like a menhir that can lean over a bit, but eventually it reaches a crucial angle where it simply falls over and is subsequently “broken”. You can see the vague assumption of design if you ask yourself: How did it get into the current arrangement?

        It’s possible that there are positive feedback mechanisms (such as newly-liberated water vapour acting as a greenhouse gas) that can lead to that sort of “breakage”. But it strikes me as very unlikely, for the simple reason that the Earth has been both much colder and much hotter than it is now, the atmosphere has both contained much more and much less carbon dioxide than it contains now, and sea levels have been both much lower and much higher than they are now. Despite clear evidence of major changes in the past, somehow or other we find ourselves in a relatively cool, temperate phase. If a “tipping point” were so easy to reach, the Earth would have reached it before now, and presumably it wouldn’t have managed to muddle its way back!

  3. Hmmm.

    “tipping point…assumes design in biology…assumes design in geology”
    No. It doesn’t. A tipping point is used of chaotic systems with many inputs. Chaotic systems are the antithesis of what most think if when they think of design.
    A tipping point does not imply fragility. A tipping point merely means that the system can remain relatively stable as a variable changes only to suddenly alter when it changes a little more. The weather is not “fragile”, but it exhibits tipping points. That’s why forecasts for next summer are not possible.

    “Despite clear evidence of major changes in the past, somehow or other we find ourselves in a relatively cool, temperate phase. If a “tipping point” were so easy to reach, the Earth would have reached it before now, and presumably it wouldn’t have managed to muddle its way back!”
    A tipping point does not mean “a point beyond which everything alters permanently”. It means a point beyond which everything changes rapidly. So it is perfectly plausible some of those changes you mention in the past were triggered by tipping points (but I can’t be bothered to check 🙂 Things like movement of the continents, volcanic activity and whallops with massive meteorites are only a few of the things that can alter the climate again.
    So the changes of the past don’t undermine the idea the global climate; they show the global climate isn’t “designed” to output conditions we happen to like. Current conditions are contingent.

  4. I refer you to the Wikipedia entry on tipping point (climatology): “a somewhat ill-defined concept, of a point when global climate changes from one stable state to another stable state, in a similar manner to a wine glass tipping over.” I prefer to use the word ‘unstable’ for the understanding of the current state, because those who speak of a “tipping point” constantly tell us that urgent action is needed now to restore stability, which assumes that stability has already been lost.

    When I use the word ‘design’, I don’t mean to impute explicit belief in a designer. Instead, I’m pointing towards Daniel Dennett’s “design stance”.

    In his flagship paper “Intentional Systems”, Dennett identified three sharply distinct approaches to explanation (description, prediction, etc.): the physical, design, and intentional stances. With the physical stance, we refer exclusively to causal mechanisms (this stance typically involves such activities as plugging values for initial conditions into causal laws, as we might when predicting the position of the planets). With the design stance, something wholly new enters the picture: it is assumed that the system under scrutiny has a “proper” working state. For example, we might explain the behaviour of a clock by assuming it keeps good time, or the behaviour of a kidney by assuming it does what healthy kidneys normally do. Although a kidney does not literally have a designer, the design stance is appropriate as a method for explaining its behaviour.

    Although the methods involved are sharply distinct, the subject matters of the three approaches often overlap, so it’s important to be clear that these are “stances” on the part of the explainer. It’s also important to see that sometimes it is inappropriate to adopt a stance for a given subject matter. For example, although it is appropriate to adopt the design stance for a healthy kidney, it is usually inappropriate to assume there is a “proper working state” for “ecosystems”, or for the Earth’s climate.

    • However I am not using the term “tipping point” to presume that the climate change is irreversible (a rather bold claim given a meteorite hit throwing up material into the atmosphere would cool the planet – I assume the actual literature is more nuanced than wiki).
      There is no design view involved in saying “the climate is X; if this action continues, a tipping point may be reached which would mean it would rapidly become Y. Y suits humans/polar bears/codfish in their current locations less well than X”. Neither “X” nor “Y” is a “proper working state”. That does not mean the “Y” will not result in the extinction of polar bears, if it happens so rapidly they cannot evolve, and if there is nowhere to move to or insufficient time for them to move.
      I get the impression you don’t like this simple conclusion that comes from the study of chaotic systems and our knowledge of evolution.

      • I can see how a chaotic system can depend on positive feedback, and I can see how a “tipping point” can depend on positive feedback, but it isn’t obvious to me how a “tipping point” can be the result of a chaotic system! Can you give a simple example of a chaotic system with a tipping point (apart from the point at which it irreversibly becomes chaotic)? Bear it in mind that I’m a bit thick, so please keep the example as simple as possible! The compound pendulum is my favourite.

        I think it’s rather unlikely that Al Gore et al are thinking of chaotic systems when they speak of a climatic “tipping point”, not least because they want to avoid suggestion that the climate is inherently unpredictable. Their main claim is that the climate is predictable, and we’re all doomed unless we take immediate action to prevent us going over “the edge” (i.e. the supposed tipping point).

        If we read between the lines of that sort of claim, it seems to assume that the Earth’s climate normally “works properly” but is in grave danger of getting “broken”. I think that’s unlikely in the case of geology (how did the Earth manage to “fix” itself in the past?) and it’s a misunderstanding of evolution. It’s inappropriate to adopt Dennett’s “design stance” in biology, except for organs within the body of an evolved organism.

        I know nothing of Al Gore’s religious beliefs, but at the risk of stereotyping, those ideas suggest habits of thought and tropes of a standard Tennessee Creationist. The Earth has been made to “work properly”, and woe betide any who don’t do what the “maker” intended, evolution “works too slowly” to establish (or re-establish) the maker’s intended “order”…

  5. Well, for an example of a tipping point in a chaotic system, how about a forest. Certain conditions make a campfire becoming a forest fire more likely, others less likely. When conditions are right a tipping point is passed and camp fires readily spread. But the system is chaotic – it cannot be precisely estimated in advance & is sensitive to initial conditions (http://www.stat.berkeley.edu/~aldous/157/Writeups/lecture_7.pdf)

    I know you tend to see religion everywhere 🙂 but I really don’t see why it must apply here. I think you are equivocating on “predictable”. Weather is “predictable” within limits but that doesn’t mean that it is inherently stable within those limits. The two concepts are different.

    I don’t know Al Gore’s background and I don’t much care 🙂 A tipping point (again) does not imply the change can never be reversed, it simply means there is a rapid effect. Think of water becoming steam. It doesn’t gradually become steam, it becomes warmer as heat is added and at a certain point becomes steam. That is a sudden effect in a narrow temp range even though it is reversible.

    The talk of “divine order” misses one simple point. Evolution does work slowly. It isn’t magic. If all the individuals of a species die, they won’t evolve. If large numbers of species die, it takes time for new species to evolve. This isn’t a guess, it’s fact, derived from the fossil record. Our current flora and fauna is no more “meant” than any other. So why do you find it so unlikely they can die out, like the other 99% of all species that have ever existed. This apparent belief in the invulnerability of our current species seems more religious (species as immutable & eternal) than a belief they’ll die out.

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