Talk:List of Patterns

Background to Draft Principles of Ecosystems (Maibritt's e-mail of January 31st, 2007)

"Many of the sources I looked at have similar lists, mainly because they tend to reference each other. Some don’t however and do offer similar information, or a slightly different take on things. Some sources did actually contradict each other, and not all the information was immediately compatible.

The sources I used were from an initial effort to find other lists of ecosystem principles or similar ideas. There are many more comprehensive sources that look in depth at specific aspects of ecosystem functioning rather than try to offer an overall view, or list, and obviously some sources I have used have more standing academically than others.

One of the conclusions I came to was that there are a number of ways to organise similar information and because of the nature of ecosystems, it is not always easy to make distinct principles as often they are linked. I expect this list will change over time and as more sources are added. I am not sure this is the best way to combine all of the information from various people or that some of the principles in the draft list are not in fact subsets of others, or that some important principles are not there yet. I did not include the matrix I have been using to compare various sources, which lead to the draft list as it is a work in progress at this stage. I did include which sources discussed various aspects of a principle though, and have included the actual lists for those sources that had one.

As I mentioned this is part of my thesis research, so is intended for a specific audience. The language I have used might not be the most suitable for an easily digestible format. I do think that such lists, particularly the simplified ones really need some kind of explanation for each principle so some of the more subtle or complex aspects of each one are not overlooked or missed out (I am working on this at the moment). Each principle represents a lot of information that might not be immediately apparent.

I have used the words tends to because there are in fact exceptions to most of these principles in nature, and have also avoided using language like natures laws etc."

--John 7 February 2007 (EST) As a fellow student engaged in a hunt for principles, I share your concern about the foundations upon which these lists are built. The propensity of authors, myself included, to reference existing lists is limiting. Moreover, the value of the listed principles will remain in question until one can operationalize and validate them. Validation in a biological context is only the first step; one must also validate them in engineering, architecture and other human-centered contexts.

While a careful and systematic review of biology literature might unearth valid biological principles, experiments, modeling and simulation are needed to validate these same principles in an engineering context. I think patterns have a part to play in this regard. Before one can interrogate a principle, one must operationalize it. A pattern based upon or associated with a particular principle might give us a blueprint for something to build and test. Building can take the form of mathematical modeling or physical experimentation. Identification of patterns might also allow us to more easily specify parameters for comparative analyses.

Eileen's note 2/4/07

I really like the lack of jargon in this document. There were only a couple points that weren't intuitively obvious to me. They are:

-Emergent effects tend to occur (what are emergent effects?)

-Diversity is related to resilience to point (what does "to point" mean?)

As opposed to the RUrban design project - what is 'dynamic fractal morphology?' 'ground truthing'? Or even our main page, which to me seems to have a bit of jargon instead of plainspeak in it. (Maybe I'm just vocabulary-challenged?)

Thanks, Eileen

--Norbert 15:23, 4 February 2007 (EST) Eileen, 'emergent effects' are (often unexpected) behavior resulting from the interaction of relatively simple agents over a period of time. Your comment about 'creating fun' vs. 'creating an environment where fun can emerge' is all about emergence and self-organization. John Todd's Living Machines is another example - the designer does not actually control how the Living Machine works, but rather creates/seeds an environment that self-organizes into a water treatment system. There is a good writeup in Wikipedia:Emergence, particularly the sections 'Emergent properties', 'Emergent structures in nature' and 'Emergence in culture and engineering'.

I'll ask Maibritt about the 'Diversity...' question. 'Dynamic fractal morphology is a mouthful - I think it describes a way of organizing cities around a relatively static framework (similar to veins in a leaf) that allow for dynamic change and interaction with other environments (e.g. rural/natural). As an aside, the same model was used in one of the projects at the Costa Rica Biomimicry workshop. As far as the main page is concerned, I am more than willing to re-write any jargon I introduced, or explain quotes in plain English.

--Maibritt 15:57, 4 February 2007 (EST) Sorry it should read 'diversity is related to resilience to a point'. Yes the wording is a bit confusing. I was trying to avoid saying something that wasn’t true, but there might be a better way of writing it.

I think a lot of people mention diversity because it is usually seen as a way to increase the stability of a whole system, which is partly true, but may not be the whole picture. As you probably know, there is quite a lot of historical debate on the subject amongst ecologists. (Shear McCann, 2000) is a good article for a quick overview. A greater number of species (more diversity) does not in itself increase the stability of ecosystems. From what I can gather it seems more to do with the number and strength of relationships between species in systems rather than actual numbers of species. Diversity does not seem to increase the stability of populations (ie the number of individuals in a species in a system) but is often related to keeping total numbers of individuals in a community (ie lots of different species) in a dynamic balance (rather than a kind of system homeostasis). So diversity is related to stability / resilience depending on how you define it but stability / resilience is not a direct result of high diversity. It might be a bit pedantic but I think the difference could be quite important in different contexts. There is evidence that decreased diversity is not a good thing for ecosystems however and that it is difficult to predict which species are ‘keystones’, the removal of which will dramatically change the whole ecosystem (its quite surprising which ones are). (Baskin, 1998) is quite an easy read.

Baskin, Y. (1998). Work of nature: How the diversity of life sustains us. Washington D.C.: Island Press.

Shear McCann, K. (2000). The diversity-stability debate. Nature, 405, 228-233.

Nick's Note 4-1-08

--Nicbec 09:26, 1 April 2008 (EDT)

• Hello all, I just jumped into the fray here, so this may be old news, but I have a comment regarding the ecosystems document. This concerns the very first rule:

1. Ecosystems tend to run on contemporary sunlight

• While this is the case is the most familiar ecosystems, ecosystems such as the deep ocean midwater (the largest continuous ecosystem on earth) and subterranean environments do not run on contemporary sunlight. They instead derive their energy and nutrients from "stored" sunlight that has its "point of sequestration" in a distinct ecosystem and temporal period. Additionally, deep sea hydrothermal vents derive their physical energy input from geological processes deep within the earth's crust, essentially independent of the sun (at least as far back as the origin of earth's geology goes). So, what about this change:

1. Ecosystems tend to run on contemporary sources of physical energy.

• However this fails to treat the temporally stored energy such as the deep ocean midwater, where the energy is stored biologically.
• Thoughts?

--Norbert 15:12, 1 April 2008 (EDT) Nick, you raise an interesting point. The Non-Equilibrium Thermodynamics thread suggests that any gradient is fair game: sunlight, biomass, dissolved minerals in 'black smokers', and by extension, fossil fuels. James Kay argued that the imperative to dissipate gradients may be at odds with the imperative to survive. I think the term 'contemporary' is key. Are we using a 'free resource' (energy or material) that is replenished at least as fast as we are consuming it? Are we created opportunities for other 'gradient dissipators' or are we forcing them out of the game? The problem is that this is much more complex than "Ecosystems tend to run on contemporary sunlight". One of the interesting things about the Patterns project is uncovering areas where the ecosystem principles need more rigor.