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Niche construction.
The neglected process in evolution
A review by Gert Korthof 16 Jul 2008
Niche construction. The neglected process in evolution.
by John Odling-Smee, Kevin Laland, Marcus Feldman (2003), Princeton paperback 472 pages.
Niche Construction is a prime example of an extension of the orthodox neo-Darwinian paradigm. According to Odling-Smee et al Niche Construction theory has important, but hitherto neglected implications for evolutionary biology.
What is Niche Construction? An analyses of what organisms do, or -more fundamental- what life is, leads to Niche Construction. Organisms take food (organic or inorganic), take other organisms as food (predators), produce waste and artefacts, thereby changing their own environments and the environments of other organisms (7). As a consequence they are modifying selection pressures of their own species and other species. Niche Construction can change the direction, rate and dynamics of the evolutionary process, because it introduces feedback into the evolutionary process. Examples: a spider's web is itself a transitory object, but it is recreated regularly, so is a constant factor not only in his own environment, but also in the environment of insects. A beaver's dam modifies many selecton pressures in the beaver's environment (fishes, frogs, herons, etc.) and is considered a keystone species.
Neo-Darwinism
The paradigm of NeoDarwinism states that individual variations survive and increase in frequency in the population according to the fit they have to the current environment. Niche Construction theory emphases that organisms are not passive elements in their environment. They control their environments to a large extent (spider). Importantly, the result is that selection –the core of NeoDarwinism– is affected. So, a complete theory of evolution must incorporate this effect. Niche Construction seeks to describe evolutionary change in terms both of the properties of environments that affect organisms and of the properties of organisms that affect environments. In short: evolution depends not on one, but two general selective processes: natural selection and niche construction.
Oxygen
The most dramatic case of Niche Construction is oxygen production by photosynthetic cyanobacteria and plants (1). It is a many-generations-effect: oxygen is accumulating over many generations. It permanently changed the physical environment of every organism, including our own species, on earth. This effect is not temporary or canceled out by opposing effects. It has an extremely strong impact on natural selection.
Ecological Inheritance
The first and wellknown inheritance system is DNA. The second is ecological inheritance. It is independent of DNA inheritance. Ecological Inheritance occurs via the physical environment. An example of the biological environment are predators. Another difference with DNA inheritance is that Ecological Inheritance potentially effects many other organisms. For any flying insect a spiders web is a new physical factor in their environment. In short, wherever there is ecological inheritance, the evolutionary process is likely to operate in a different manner from that described by Standard Evolutionary Theory (SET).
Adaptation
Adapation in evolutionary theory can be described as an answer to the problem posed by the environment. But in Niche Construction theory the environment is no longer autonomous, but is partly influenced by the organism itself. In general when there is a fit between organism and environment (adaptation) this is caused by the organism has adapted to its environment or the organism has changed its environment. Examples: the spider creates a sticky web. Next the spider himself inherits a sticky web to which he himself has to adapt to by natural selection (do not stick to your own web!). The earthworm (2): without ancestral niche construction by many organisms, including earthworms, topsoil would not exist, so how could earthworms adapt to it?
Organism and climate
A cow eats grass, and defecates in its pasture and produces methane (3). Here is a general principle that holds for all organisms. To stay alive all organisms need energy. They get energy from their environment. Secondly, they dispose their detritus in their environment. So all organisms change their environment in two ways. These effects on the environment are left out of standard accounts of the theory of evolution which are about adaptation and genes. But biological evolution has consequences for organisms as well as for environments. Methane constructs our global atmosphere. The atmosphere is a common abiotic environment. Since methane is a greenhouse gas, the link with climate and global warming becomes clear. Forests influence the CO2 cycle and the hydrological cycle (rainfall, cloudformation). Climate change by organisms is an example of Ecological Inheritance (4). Niche Construction helps us to see this. Neo-Darwinism is not very helpful in this respect.
Humans
The humans species has the greatest power to change the environment (5). So, human Niche Construction is a very important aspect of human evolution (chapter 6 and 9). Humans introduced agriculture and domestication of animals. Cattle introduced selection pressure on a human gene that enables the enzyme lactase to be active in adults. Domesticated animals also introduced humans to new diseases such as measles, tuberculosis, flu and smallpox. This created selection pressure for resistance. The authors propose a triple inheritance: genes, memes and artifacts.
Praise and criticism
The authors are very careful when proposing an Extended Evolutionary Theory (chapter 10). They admit that standard evolutionary theory undoubtedly enjoys the advantage of theoretical simplicity, and this should not be given up lightly. They examine two questions: What do we stand to lose if we stick to standard evolutionary theory in spite of its limitations? What do we stand to gain if we substitute extended evolutionary theory for the standard theory? These are excellent questions. I agree that -for example- the core Darwinian concept adaptation becomes more adequate if we include niche construction (example: earthworm). Niche construction can be very important in constructing a bridge between Earth System Science and the standard theory of evolution.
One of my few criticisms is that prime examples of niche construction, such as the photosynthetic oxygen niche construction (climate in general) and niche construction by corals, are only very briefly discussed in the book. Coral reefs support an extraordinary biodiversity, are home to a variety of tropical or reef fish, are also home to a large variety of other organisms, including sponges. By definition a reef is a rigid, wave-resistant structure, and thus can form "instant rock" which becomes part of the world's coastlines (6). In other words: ecological inheritance and a definite effect on natural selection. On the other hand, there is a lot of mathematical elaboration of niche construction, however it seems at the expense of biological examples. Finally, a remark about the word 'Niche Construction'. What humans do to the earth is not always adequately described as 'Niche Construction'. It is often more appropriately described as 'Niche Destruction' (5).
Notes
- Although this seems to me the most dramatic case of niche construction, remarkably, the authors discuss it very briefly. How strange!
- Earthworms change the structure and chemistry of the soils in which they live and, by constructing their environment, modify selection acting back on themselves, for instance, influencing their water-balance organs. Please note: Darwin wrote about earthworms! Maybe he came very close to niche construction!
- Methane is not in the index!
- An example of an abiotic effect of life:
"The only plausible explanation of the annual [CO2] wiggle and its variation with latitude is that it is due to the seasonal growth and decay of annual vegetation, especially deciduous forests, in temperate latitudes north and south. The asymmetry of the wiggle between north and south is caused by the fact that the Northern Hemisphere has most of the land area and most of the deciduous forests. The wiggle is giving us a direct measurement of the quantity of carbon that is absorbed from the atmosphere each summer north and south by growing vegetation, and returned each winter to the atmosphere by dying and decaying vegetation. (...) When we put together the evidence from the wiggles and the distribution of vegetation over the earth, it turns out that about 8 percent of the carbon dioxide in the atmosphere is absorbed by vegetation and returned to the atmosphere every year."
The Question of Global Warming by Freeman Dyson.
- Caused by human brainpower and technology. Initially, in human history ecological changes were local, but gradually became more of a planetary scale (deforestation, climate change, overfishing, ocean acidification. pollution, fossil fuel depletion). Obligatory reading is: C. Roberts (2007) The unnatural history of the Sea. The past and future of humanity and fishing (review). Example: "The removal of whitefish from New England waters had opened up a niche that dogfish and rays were quick to exploit."(p.213). "Removing a voracious, broad-spectrum predator like cod from the Gulf of Main profoundly affected nearshore ecosystems. ... With the cod gone, invertebrate numbers exploded. Immense numbers of grazers [sea urchins] cleared the seaweed forests. Then fishers took the sea urchins away until the population collapsed. Then an alien species of seaweed started to spread like weeds." (p.217). etc. ect.
About coral reefs: "The viability of the world's major coral reefs is endangered both by direct human disturbance and by disease and bleaching events brought on by climate change." (Science, 25 jul 2008). Therefore, the concept Niche 'Construction' has a too positive meaning. What humans usually do is better described with 'Niche Destruction'.
- See: Coral reefs; Importance of coral reefs and Review Darwin's Classification of Coral Reefs.
- This is how Frances Arnold and Joseph Meyerowitz describe a genome: "Genomes are great books of instructions on 'how to': how to extract materials and energy and convert them into self-repairing, self-reproducing machines; how to function in an extraordinary range of environments; even how to adapt over the long term." in: Nature, 8 May 2014, Synthetic biology: Engineering explored. They omit waste products and niche construction!
Reviews
- Review in Science 23 January 2004 by John Vandermeer.
"On balance, the book offers a persuasive case for the crucial importance of understanding the construction of
niches by organisms. With this volume, we may indeed be looking at a major breakthrough."
- Review in Evolutionary Psychology, 2005, by Thomas E. Dickins.
"But, as argued above, the full explanation for lactose tolerance relies, in the end, on natural selection."
- Review in Perspectives in Biology and Medicine, 2004, by David L. Hull.
"Of all the innovations that the authors of this book introduce, ecological inheritance is the most problematic. Because it is so non-standard, it has to be approached from several different directions in the context of real examples. The authors realize that clear exposition is not enough: they must provide evidence for their theory and show that niche construction can explain these data better than any other evolutionary processes. They also have to show that niche construction is widespread, significant, and at least partially independent of natural selection. In this book they have succeeded on all counts. In fact, the authors have fulfilled all the requirements for genuine science so well that I find it difficult to see how anyone will be able to ignore their Extended Evolutionary Theory."
Further Reading
- The Niche Construction website of the authors of the book.
- Niche Construction in google books.
- Niche Construction in wiki.
- K. N. Laland, F. J. Odling-Smee, and M. W. Feldman (1999) Evolutionary consequences of niche construction and their implications for ecology, PNAS August 31, 1999 vol. 96 no. 18 10242-10247. (abstract is free).
- James Lovelock (2000) The Ages of Gaia. A Biography of our Living Earth. (review)
- John Kricher (2009) The Balance of Nature: Ecology's Enduring Myth, Princeton University Press. info. ("John Kricher demonstrates that nature in fact is not in balance, nor has it ever been at any stage in Earth's history").
- Robin Dunbar (2005) 'Evolutionary Psychology' mentions Niche Construction favourably.
- Kevin N. Laland, John Odling-Smee, Sean Myles 'How culture shaped the human genome: bringing genetics and the human sciences together', Nature Reviews Genetics 11, 137–148 (February 2010) (pdf).
- Kevin N. Laland, Kim Sterelny, John Odling-Smee, William Hoppitt, Tobias Uller (2011) 'Cause and Effect in Biology Revisited: Is Mayr's Proximate-Ultimate Dichotomy Still Useful?', Science 16 Dec 2011. (discusses niche construction). 21 Dec 2011
- Scott-Phillips TC, Laland KN, Shuker DM, Dickins TE, West SA. (2014) The niche construction perspective: a critical appraisal. Evolution May 2014. Very useful article, it shows in an exemplary way how to evaluate a scientific theory.
 free pdf.
- "Here, we subject NCT [niche construction theory] to critical evaluation ... We discuss whether niche construction is an evolutionary process, whether NCT obscures or clarifies how natural selection leads to organismal adaptation, and whether niche construction and natural selection are of equivalent explanatory importance. We also consider whether the literature that promotes NCT overstates the significance of niche construction, whether it is internally coherent, and whether it accurately portrays standard evolutionary theory. Our disagreements reflect a wider dispute within evolutionary theory over whether the neo-Darwinian synthesis is in need of reformulation, as well as different usages of some key terms (e.g., evolutionary process). "
Does Niche Construction Theory (NCT) make predictions or derive new insights that cannot be made with Standard Evolutionary Theory (SET)? Example: Lactose Tolerance in Humans.
- Kevin N. Laland, Kim Sterelny (2007) PERSPECTIVE: SEVEN REASONS (NOT) TO NEGLECT NICHE CONSTRUCTION, Evolution, 08 May 2007. " We conclude that none of these [7 arguments] are strong criticisms of the niche-construction perspective and maintain that there are compelling reasons for treating niche construction as a major evolutionary process.".
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