All posts by Rolf Muertter

I studied biology at the Johannes Gutenberg Universität in Mainz, Germany. My main interest then was population genetics and ecology. After five semesters I decided that I needed a new approach to understanding how nature works, so I enrolled in the physics program at the University of California in Riverside. My main interest there was astrophysics and cosmology, so I got involved with the high energy astrophysics group, researching cosmic rays, gamma ray bursts, and building a gamma ray telescope. After graduating with a M.S. in physics in 1996, I went to work as an engineer in Silicon Valley. There I discovered bioinformatics and got really excited about it, so I took some bioinformatics related classes from the University of California in Santa Cruz. I eventually got a job as a scientific programmer at a biotech company in Palo Alto, and from 2007 to 2011 I worked at the National Center for Biotechnology Information in Bethesda, Maryland. Ever since I was a kid, I had quite an affinity for the natural world. Growing up in the suburbs of Philadelphia, I was fascinated by the great variety of frogs, salamanders, fishes, and other creatures in the area. When I was ten, we moved to the city of Hamburg, Germany, where museums and the harbor took the place of frogs and salamanders. I found them to be almost as fascinating, but I still dreamt of becoming a biologist. In my early twenties I had my first epiphany. I read that modern agricultural practices lead to a net loss of topsoil, and are therefore unsustainable. Since then, I've learned about many other aspects of our behavior that are considered unsustainable, which made me wonder about the concept of sustainability, and what it really means in an ecological and evolutionary context. My response at the time was to become an environmental activist, but deep down, I knew that our increasing ecological footprint was hinting at something very profound about human nature. I began to realize that in order to understand (living) nature, you have to understand human nature. So I switched my focus as a naturalist from the orchid genus Ophrys to the mammal genus Homo. Conservationists often use moral arguments as a reason to protect nature, which made me wonder about the nature of morality. Studying sociobiology and evolutionary psychology led to my second epiphany, which was that morality is not just cultural, but part of human nature. It is therefore an adaptation that helps individuals survive in a complex social environment, and it definitely did not evolve in order to ensure the survival of other species, or even that of our own species. In 2006 I had my third, and most important, epiphany, by changing my focus from psychology to ecology. Understanding why humans are so dominant is really an ecological question, so I asked the obvious question: What is the human ecological niche? The answer commonly given, that we are hunter-gatherers, might have been true in the past, but it doesn't describe the role we play in the biosphere today. It's not hunter-gatherers that are transforming the Holocene into the Anthropocene. Answering the question What is the human ecological niche? led me to realize that we are global Darwinian demons, and it is this aspect of human nature that is responsible for the current evolutionary transition to a human-dominated planet.

Are Humans the most Advanced Species?

2018/02/11 Rolf Muertter Leave a comment

It should be obvious to anyone by now that there is something special about the human species. We are the most dominant species the planet has ever seen. How did this happen? Does intelligence always lead to dominance once it passes a threshold? Are we the most highly evolved or most advanced species? Does it even make sense to say that some species are more advanced than others? (I was inspired to answer this question by similar questions asked on Quora, for example here and here.)

Since the Copernican revolution, there have been many similar revolutions that kept moving us further from the center of the universe. For example, we now know that the Milky Way is just one among billions of galaxies, and that our planet isn’t even close to the center of it. More recently, many of these revolutions have come from biology. For instance, we now know that we’re just one of about five thousand species of mammal, that there are other species that have figured out how to use tools, and that some species even have culture, such as the various hunting techniques that orcas use. Some species have better memories than we do, can count better, and apparently some are as much capable of empathy as we are. Not only are dolphins possibly even more intelligent than chimpanzees, they also develop self-awareness at an even younger age than humans. It even looks like we’re not the only fire manipulating species anymore (also see here). The more we learn about other species, the harder it gets to find anything that makes us exceptional.

To some, the ultimate symbol of how far the Copernican revolution has advanced might just be the latest phylogenetic tree that has been constructed of all 2.3 million known species. In this “tree of life” we are just one of millions of leaves, prompting many to proclaim how utterly insignificant we are in the big scheme of things. Obviously, they are committing the fallacy of equating length of development time with competitiveness of the product. With this view, the modern Copernican revolution has now overshot its goal of a scientifically realistic assessment of our place in nature. Just based on our ever-increasing ecological footprint, we know that we are the dominant species on Earth, and the data are so solid that many scientists are calling for a renaming of the current geological epoch — the Holocene — to the Anthropocene.

It should be emphasized that it’s not normal for there to even be a dominant species. Before us, there has never been a dominant species on Earth, and there is nothing in ecological theory that would predict the emergence of such a species. Conversely, ecological theory has no trouble modeling species coexistence and biodiversity. So we need to look elsewhere for an explanation of human dominance.

It’s commonly believed that we are so dominant because somehow we’ve evolved to become the most advanced species. But what does “most advanced” mean, and how did it happen? We all know what it means in the context of technology. An electronic hand-held calculator is obviously more advanced than an abacus. It took a lot longer to develop, it has way more useful features despite being smaller, cheaper, and faster, and is therefore better adapted to the hand-held computing niche and can easily out-compete any abacus. Just as our industrial products require more development effort in order to remain competitive in the marketplace, so do more complex and effective biological adaptations typically require longer periods of natural selection to evolve. This suggests that we define the more advanced biological species as the one that is sufficiently adapted to its ecological niche that it can out-compete any other species in that niche.

Munz's onion — Munz’s onion. Photo taken by author at Lake Skinner, California, in 2003.

By that definition, doesn’t it mean that all species are equally advanced? If we disregard humans for a minute, I’d agree for the most part. After all, all extant species have survived billions of years of evolution. By far most species that ever existed have gone extinct. The species we see today are the few that survived — they are the absolute champions in their respective niches. In other words, every species is the most advanced species in its own niche. And it doesn’t matter whether we’re comparing a rare endemic such as Munz’s onion (Allium munzii) with a globally common species, such as the common raven; within their niches they are equally successful. Some niches just happen to be bigger than others.

Species do occasionally go extinct. Sometimes it’s because of some disaster, such as a large volcanic eruption that affects many species equally. It’s just bad luck, and doesn’t mean the species weren’t advanced enough to survive. However, sometimes it happens that a competing species becomes a bit more competitive than another, perhaps because it adapts a little faster to a changing environment, and the other species goes extinct. In that case one could say that the faster adapting species was more advanced than the species it replaced. However, this doesn’t happen very often, and all we see now are the winners.

On a larger scale, one could argue that some groups of species are more advanced than other groups of species, depending on geography. For example, island species have coevolved with fewer species, and therefore they’ve evolved fewer adaptations that are needed to be competitive with other species. That’s why the proverbial dodo went extinct so quickly after human contact, whereas the equally flightless ostrich is still around.

Another example, but on an even larger scale, is the north-south asymmetry in species migration when the Isthmus of Panama was formed around three million years ago. Before then, South America had been isolated from North America and only occasionally connected to Antarctica and Australia, with some limited species exchange taking place. But once North and South America were connected, there was a surge in species migrations, also known as the Great American Interchange. However, way more North American species managed to successfully invade South America than vice versa. Why the asymmetry? The Wikipedia article on the Great American Interchange offers this explanation:

“… Northern Hemisphere species arose over a land area roughly six times greater than was available to South American species. North American species were thus products of a larger and more competitive arena, where evolution would have proceeded more rapidly. They tended to be more efficient and brainier, generally able to outrun and outwit their South American counterparts, who were products of an evolutionary backwater. These advantages can be clearly seen in the cases of ungulates and their predators, where South American forms were replaced wholesale by the invaders.”

A more recent example is the difference in invasiveness of North American versus Eurasian species. There are way more nonnative invasives of Eurasian origin in North America, and they are ecologically and economically more destructive (e.g. tamarisk, rip-gut brome, zebra mussel), than vice versa (e.g. goldenrod, lupines, raccoon). The reason for this asymmetry is that Eurasian species have been exposed to humans for much longer, so they are better adapted to our presence. And considering that human dominance is only going to increase in the future, it’s hard to imagine a more future-proof adaptation than the ability to coexist with humans. Therefore, the more a species is already adapted to our presence, the more evolutionarily advanced one could say it is.

To summarize so far, it is possible for some species to be evolutionarily more advanced than other species that occupy similar niches, as long as they are isolated from each other. Once they come into contact, the more advanced species will usually displace the less advanced species.

For the benefit of those who are less steeped in ecological thinking, consider another example from technology — automotive evolution. The first car, the Benz Patent-Motorwagen, was built in 1885. Within the next few years, two new models came out, each one with nifty new features, such as a fuel tank, or leather shoe brakes. Today there are hundreds of models, and still every year new models come out that are more advanced than previous ones. And yet, even after 130 years of car evolution, all models are roughly equally advanced. They have to be, because in today’s hyper-competitive global free market economy, any model that’s not competitive will be discontinued. Sure, some models are faster, but others get better mileage. Some have more advanced electronics, but others are more affordable, or more easily maintainable. So there are always tradeoffs, but every model has to be competitive in its own niche.

However, just like in the world of biological species, this isn’t always the case. Consider the Trabant, which first went into production in 1957, and remained virtually unchanged until 1991. How was this possible? Well, it was produced in East Germany, which was part of the Eastern Bloc and didn’t have a free market economy. Without any competition from manufacturers outside of the GDR, there was no pressure to innovate. As a result, production ceased shortly after

Abandoned Trabant — Many Trabants like this one, photographed in Leipzig in 1990, were abandoned after 1989.

the wall came down in 1989. Suddenly exposing a market that’s been protected for a long time to global free market forces is like introducing rats and goats and other more competitively evolved species to evolutionary backwaters such as remote islands, and we all know what that does to the native fauna and flora.

Now that we’ve established that some species can be more advanced than others, let’s take a step back and think about the bigger picture. Ultimately, life is really about competition for resources. Whether a species can successfully exploit a particular resource depends on its genes, and every generation a population gets a new shot at producing variants that are better at it. The problem is that competitors do the same, resulting in a never-ending evolutionary arms race. Now, the rate of evolutionary change isn’t always constant, and sometimes a species does get the upper hand and manages to become more successful. But soon the tradeoffs start kicking in. For example, a larger population makes for a bigger target for predators and parasites to adapt to. Invoking the Red Queen metaphor, species have to evolve as fast as they can just to stay where they are ecologically. This makes for a pretty stable system, with levels of biodiversity tending to increase over time, unless there is a catastrophic event like an extreme volcanic eruption, or an asteroid impact.

“Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!”

– The Red Queen to Alice in Alice Through the Looking Glass by Lewis Carroll.

Now try to imagine what would happen if any species ever came up with a new way of adapting to its environment, one that’s significantly faster than the conventional genetic one, say, two or three times faster. Not only would it quickly displace other species with similar niches, it would rapidly adapt to other niches and outcompete species there as well. If it can adapt fast enough, tradeoffs will be less of an issue, resulting in a runaway increase in dominance. It would obviously be the most evolutionarily advanced species in its ecosystem. (This kind of organism is called a Hutchinsonian demon.)

You may think that a species so advanced could never emerge, since in the 3.8 billion year history of life it’s apparently never happened. However, we now know that it is possible because it’s happening right now! The species that finally managed to beat evolution at its own game and take the art of adaptation to the next level is of course us — Homo sapiens. And the situation is actually way more extreme than the hypothetical scenario I just laid out. While other species are still running as fast as they can, we found the turbo button, and pushed it, accelerating us to evolutionary rates that are now ten to one hundred thousand times faster, with no end in sight. How did we do it? The trick we came up with is known as cumulative cultural evolution.

It began around three million years ago when we started making stone tools. The first tools were quite primitive and didn’t change much over long periods of time; sometimes there was virtually no change in over 100,000 years. However, during the Pleistocene, which began 2.6 million years ago, the increase in brain size and tool-making innovations accelerated. We may never know exactly why it happened then, but the most convincing and succinct explanation I’ve seen so far is offered by Peter Turchin in Ultrasociety:

“Generally speaking, the capacity for culture should evolve (assuming that such pre-adaptations as sophisticated cognitive abilities are in place) when the environment changes too fast for genetic adaptation to work, but slowly enough for information accumulated by previous generations to be useful. If environmental change is faster than that, you are better off learning everything yourself, even though it’s risky and inefficient. During the Pleistocene, apparently, environmental change was just right — not too rapid, not too slow, and very violent — to drive the evolution of culture. It’s not a coincidence that many other mammals evolved large brains in parallel with humans.”

And then something else happened: we evolved the ability to communicate symbolically using language. This greatly enhanced our capacity for social learning, which in turn increased the rate at which innovations could spread and build on each other. This greater rate of innovation allowed us to exploit new kinds of resources in cognitive time (at the speed of thought), instead of in genetic time (measured in generations). (If you want to learn more about how cultural evolution made us the most advanced species ever, check out Joe Henrich’s The Secret of Our Success: How culture is driving human evolution, domesticating our species, and making us smart.)

For example, what would it take for a water-loving terrestrial animal, like Pakicetus, to be able to take advantage of the abundance of food in the oceans? It would take about ten million years of genetic adaptations until it became as well adapted as a whale. It took us humans only a few generations to figure out how to fish with boats, spears, and nets, and our ability to compete in this niche is now so advanced that many marine species are threatened. Most whale species would probably be extinct now if some of us didn’t try to protect them.

This doesn’t mean that genetic evolution has become irrelevant to us. For example, consider one of our very early cultural achievements, the use of fire, which goes back about a million years. One of the first uses of fire was for cooking, which made many foods easier to digest. This meant that we didn’t need as large of a gut as that of a typical omnivore, freeing up resources to build an even bigger brain, one that’s even better at social learning. This also illustrates that genetic and cultural evolution influence each other, a process known as gene-culture coevolution. Some of these genes, for example genes for language, are a direct result of our adaptation to cultural evolution, which makes it part of our biology.

Earlier I mentioned that it’s hard to find that one trait that sets us apart from all other species. Could gene-culture coevolution be it? There is actually one other species that we share this trait with: orcas. Over many thousands of years, different orca populations have developed different hunting techniques, and as a result, they have become genetically isolated from each other. So because of cultural evolution, there are now five subspecies of orcas. They are obviously a very successful species, and as the global marine apex predator, they do occupy quite a significant niche. However, they are not a Hutchinsonian demon. What they don’t have is cumulative cultural evolution, and this is the trait that makes the human species a global Hutchinsonian demon.

The reason why this makes us more advanced than other species is that the greater rate of cultural evolution allows us to out-compete any species for any resource. It used to be that, as hunter-gatherers, we occupied our own ecological niche, distinct from that of other species. This meant that there was limited competition with other species for a limited set of resources. This is no longer the case. We are now — directly or indirectly — competing for all resources that all other species need, and we occupy more than one niche, namely as many as there are professions. Some professions are analogous to nonhuman niches; for example, fishermen compete directly with orcas or osprey for the same fish. Other professions don’t have obvious analogues, such as web programmers. However, there is still competition for the same basic resources. Web servers, for example, need electricity to run, which can be produced with solar energy, and solar power plants compete with green plants for the same space to collect sunlight. We’ve been clearing land for our own purposes for thousands of years, but with modern machinery the process has become very fast and efficient. It’s not even a contest anymore.

In order for an organism to effectively compete for resources, it needs to specialize. If the set of all resources needed by all life is the entire pie, then each species only gets a tiny slice. So assuming there are ten million species, each species gets on average one ten millionth of the pie. Until recently, this also applied to humans, but now — thanks to cultural evolution — our share has grown to half the pie, and it’s still increasing rapidly, with no end in sight. And due to the mechanism, the process is irreversible; therefore, our share of the pie is guaranteed to grow close to 100%, resulting in the sixth mass extinction. After previous mass extinctions, life got back to business-as-usual, eventually even surpassing previous levels of biodiversity. This time is different. This is no ‘ordinary’ mass extinction, but is better described as an evolutionary transition from a biodiversity-based biosphere to one based on techno-diversity.

Darwinian Demonology

2013/12/02 Rolf Muertter 3 Comments

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In the history of science, thought experiments have often played an important role, either by helping to refute established theories, for example Galileo’s Leaning Tower of Pisa experiment, which refutes Aristotelian gravity, or by helping to conceive of new theories, for example Einstein’s special (chasing light beam) and general (elevator) theories of relativity. Sometimes the results of thought experiments appear counterintuitive, or even to violate the laws of nature, even though the assumptions all seem obviously correct. Of course this would have to be the work of a malevolent, supernatural being, so a demon is blamed.

Maxwell’s Demon

The most famous example is Maxwell’s demon. This demon appears to violate the second law of thermodynamics by operating a door in a small hole in the partition between two containers, and only letting fast molecules pass into one of the containers, resulting in an increase in temperature difference over time. However, a more careful analysis, which includes the demon’s metabolism as part of the system, shows that the second law isn’t really violated. So if you know your physics, there really is no need to invoke a demon.

Most thought experiment demons are found in physics or philosophy, but biology also has one, the Darwinian demon. There are actually, as far as I can tell, four different kinds of Darwinian demon.

Law’s Demon

The first one was mentioned by Richard Law in a 1979 paper [1] on the life history effects of age-specific predation. He observes that there are always constraints on reproduction, of which predation is just one. By contrast, an organism that can reproduce without incurring any costs, and which in general can maximize all aspects of fitness simultaneously, is a Darwinian demon. This is an organism that reproduces immediately after birth, utilizes all resources for reproduction and lives forever. It’s mentioned only once at the beginning of the paper, and is of no significance for the rest of it. However, as a meme, it’s struck a chord with many since then, and has taken on a life of its own and evolved.

Invasive Species

The most familiar product of Darwinian demon evolution is the invasive species. These are species that were introduced from outside their native distribution, and may eventually become so dominant that they become ecologically and sometimes even economically disruptive. Traits that many invasives have in common include fast growth, rapid reproduction, and high dispersal ability, traits that also characterize Law’s demon. Invasives aren’t quite as demonic as Law’s demon, but have the unfortunate trait of real-life existence — as opposed to just being the product of a thought experiment. They are what I call local Darwinian demons. For example, the brown tree snake (Boiga irregularis), which was introduced to Guam from Southeast Asia, has been devastating to the fauna of Guam, but it hasn’t spread beyond Guam yet. The term ‘local’ isn’t just meant in the geographical sense, but also in terms of ecological niche breadth. Even invasives have to coexist with each other to varying degrees. Very few invasives are as dominant as zebra mussels (Dreissena polymorpha) or kudzu (Pueraria spp., a.k.a. the vine that ate the South), and even they coexist with a few other species.

Mysterious Dominance

Since the main trait of invasives and any other Darwinian demon is dominance, why not call any species that exhibits any level of unusual or inexplicable dominance — no matter how fleeting or subtle — a Darwinian demon? This seems to be the most common use of the term today, and is wonderfully illustrated in Jonathan Silvertown’s book Demons in Eden [4]. One of the poster species for this sort of demon is duckweed (Lemna minor). Duckweed is native in most of the Northern hemisphere, and is known to often behave like an invasive within its native range. It can go from a few individuals that have survived the winter to completely covering entire bodies of water within a few months. An example can be seen in the featured photo, which was taken in the Mittellandkanal in Northern Germany. One reason it can reproduce so quickly is because it does so asexually, another is that it takes advantage of an abundance of nutrients from agricultural run-off, some of which are otherwise limiting factors for water plant growth, such as phosphorous.

Some Forest fruits from Barro Colorado Island

But most examples of demons in Silvertown’s book exhibit far lower levels of dominance. He writes about biodiversity research on Barro Colorado Island in Panama, which has over 500 tree species on 15.6 km², and any species that takes up more than its fair share of the island he calls a Darwinian demon! An even more extreme example of his liberal use of the designation as Darwinian demon is his claim that every species that ever existed must once have been a demon since it must have started from a small population. This, of course, can’t be true, since most species arise as a result of geographic separation, which does not require a change in population size. But I have a lot of sympathy for his enthusiasm for adaptive radiation and ecological speciation. (Why will become clear in an upcoming article.)

Leimar’s Demon

Fitness Landscape-3D — 3D Fitness Landscape. The vertical axis represents fitness, the horizontal axes genotypes. The blue trajectory could be the work of a Leimarian demon since it gets to the global fitness maximum without a reduction in fitness along the way.

A very different kind of Darwinian demon emerged in 2001 with the publication of a paper by Olof Leimar [2]. This one resembles Maxwell’s demon in that it creates nonrandom fitness-enhancing mutations. Normally, mutations are random, and almost all of them are fitness-reducing. Of course, this kind of demon also doesn’t exist, but it’s a useful modeling tool for exploring the evolutionary potential of life. Due to the random nature of mutations, an organism may never make it from a local to a global fitness peak (green path in the image on the right), but this Darwinian demon knows where in the fitness landscape the global fitness peaks are located and creates exactly those mutations needed to get there (blue path).

Hutchinsonian Demon

The fourth one is the Hutchinsonian demon, named after Evelyn Hutchinson, a pioneer in the field of community ecology. This is the community ecology demon, introduced by Kneitel & Chase in a 2004 paper on trade-offs in community ecology [3]. Trade-offs are one of the main reasons why high levels of biodiversity are maintained in ecosystems. For example, consider defenses against predators. Turtles are heavily armored but slow, but if a predator is hungry and persistent enough, it can still occasionally manage to eat one. Lizards are quick, but if caught can easily be eaten. The trade-off is obvious, but a Hutchinsonian demon would not only be more heavily armored than a turtle, it would also be even quicker than a lizard. Of course, there are many more kinds of trade-off, such as cold versus hot climate or diurnal versus nocturnal adaptations. A Hutchinsonian demon dominates a community “because it is the best at colonizing new patches, utilizing all the resources, avoiding predators and resisting stresses” [3]. Generally speaking, Darwinian demons don’t have to worry about trade-offs. That’s what makes them so demonic.

As I’ve mentioned at the beginning, demons typically don’t really exist – they’re just thought experiments. Invasives and Silvertown’s demons are one exception, but what about Hutchinsonian demons? One might think that invasives would qualify as Hutchinsonian demons, except that species are very rarely intrinsically invasive — they acquire their invasiveness through human actions. They are species that humans have taken out of the coevolutionary network they evolved in — where they face the same kinds of trade-offs that other species in their native community do — and put them in a new environment where they face fewer trade-offs, which gives them an unfair advantage (such as a lack of predators and parasites) over species in their new community. Moreover, invasives still face some trade-offs, which limits their ability to spread to new habitats or geographical areas. You won’t find zebra mussels dominating any terrestrial habitat, and kudzu only ate the South, not the North.

And yet, I do believe that a real-life Hutchinsonian demon exists. Considering the ubiquity of trade-offs in real life, it may be hard to image that such a mythical beast could be real. Could there really be an animal that is better armored than a turtle and quicker than a lizard? (And that’s only one trade-off.) You don’t have to go very far to see this species — just get in your car! Not only could you get away from any predator chasing after you; if you did stop, you’d still be safe inside the car. And this applies to any habitat, even those we normally don’t live in, like the ocean. It doesn’t take much of a boat to get away from the most formidable oceanic predator, a pod of orcas. And even if they did catch up, you’d still be safe and could enjoy watching them. Indeed, I am talking about us humans as global Hutchinsonian demons.

While it’s commonly known that humans don’t have any predators, and are unsurpassed in resisting stresses, it may be less appreciated how important the other two defining characteristics of Hutchinsonian demons are for understanding our ecological nature. To some environmentalists our superior ability to colonize new patches is just a euphemism for “invasive cancer of the Earth”. If we want to settle somewhere we do it; we don’t let any other species get in the way. And if other species are already there, we just remove them, no matter what species. No other species has ever had this luxury. But I believe that our most demonic characteristic is our ability to utilize all resources. Every species occupies an ecological niche, which means that it specializes in using a specific set of resources. There is a wide spectrum from extreme specialists to generalists, but even generalists aren’t even close to being able to utilize all the potential resources in their environment. Bears, for example, don’t eat wood like termites do, or catch flying birds like peregrine falcons. Humans, on the other hand, can not only outcompete any species for any resource, we can use resources that no other organism can, such as fossil fuels, nuclear energy, water in deep aquifers, solar power where plants can’t grow, etc. As a matter of fact, we can take advantage of any resource that is theoretically exploitable; in some cases it may just be a matter of time until the proper technology is developed, in others it’s a question of whether exploitation is economical. This is why I like to answer the question of what our ecological niche is with “All of them!”.

Cultural Evolution as a Cultural Version of Leimar’s Demon

So how did we become global Hutchinsonian demons? Interestingly, another Darwinian demon may be involved. As I will explain in greater depth in a future article, the main reason we are so dominant is because we’ve invented a new form of evolution that is much faster than genetic evolution, and that is cultural evolution. Another advantage of cultural evolution — besides being faster — is that we can come up with radically new concepts without having to implement inferior intermediate versions. This is why we were able to invent the wheel; it could never evolve through genetic evolution. Our minds can simulate different versions of new concepts and discard those that appear to be inferior. So we can go straight from one adaptive peak (legs) to an even higher one (wheels) while avoiding the valley of maladaptedness. Sound familiar? Yes, this does look like a cultural version of Leimar’s demon.

What does the Emergence of a Global Darwinian Demon mean for the Biosphere?

Finally, I would like to emphasize the significance of the real-life existence of any global Darwinian demon (from now on, when I refer to humans as Darwinian demons, I really mean global Hutchinsonian demons). Since it can utilize any resource and outcompete any organism for any resource, it follows that its dominance must also continue to increase. And if it can evolve much faster than other organisms, none of them will ever be able to catch up and begin to impede this increase in dominance. As a result, the dominance will eventually be complete, which of course is bad news for other species. In other words, the emergence of a global Darwinian demon will always lead to an evolutionary transition. As far as we know, this has never happened before in the history of life, but this is the situation we are in today.

Objections

I know that some will disagree with this line of reasoning. The main objections to a significant increase in human dominance seem to be:

Education. If we just do a better job educating people about how detrimental our impact on nature is, we will change our behavior to lessen our impact.

Demographic transition. All we have to do is encourage birth control and empower women; that will automatically take care of the population problem.

Ecosystem services. All we have to do is put a dollar value on all ecosystem services. Seeing the great economic value of healthy ecosystems will be incentive enough to do whatever it takes to halt the degradation of ecosystems. If we don’t take action, the loss of ecosystem services will lead to the global collapse of civilization, which will end the era of human dominance.

Sustainability. Natural ecosystems and some traditional cultures apparently are sustainable, which proves that sustainability is possible, and we can learn from them. Elinor Ostrom received the Nobel prize in economics for showing that we can avoid the tragedy of the commons.

Biophilia. Since the love of nature is part of human nature, we will do more to reduce our ecological footprint once we see that the beauty of nature is vanishing.

Ethics. We have a moral obligation to preserve nature for future generations, and other species have as much a right to exist as we do.

If I’ve missed any, please let me know. In future articles I will shed some scientific light on each of these objections and show that they have more to do with wishful thinking than with reality.

Conclusion

That humans are ecologically dominant and an increasing threat to the existence of natural ecosystems is well known. However, it is usually treated as a political/sociological/economic/ethical issue. But the unprecedented ecological dominance of one species is ultimately an ecological phenomenon. So what I have done is to examine it in the scientific light of ecology, with the result that we are global Darwinian demons. I believe that this new view of human nature has the potential to make a significant contribution to the consilience of biology and the social sciences.

References

1. Law, R. (1979). Optimal Life Histories under age-specific Predation. American Naturalist 114: 399-417.

2. Leimar, O. (2001). Evolutionary Change and Darwinian Demons. Selection 2(1-2):65–72.

3. Kneitel, J.M. & Chase, J.M. (2004). Trade-offs in community ecology: linking spatial scales and species coexistence. Ecology Letters, 7, 69–80.

4. Silvertown, J. (2005). Demons in Eden. The paradox of plant diversity. Chicago and London: Chicago University Press.