BABY SERVICES

Ask not what your planet does for you …
A shorter version of this article was published in Conservation Magazine

Kai M. A. Chan

I recently spent twelve weeks on paternity leave, enjoying the many benefits that my baby provides me—free of charge. I call them ‘baby services’.

That’s one way to explain my parental leave to people who otherwise don’t get it, but to most people it’s jarringly absurd. Yet—as I realized one sleepless night—it parallels the way that I and many others have been explaining our ecology and conservation work through ‘ecosystem services’. Just as ‘baby services’ overemphasizes the me-first benefits of children, an extreme ‘ecosystem services’ narrative overemphasizes the passive reception of benefits and extends the sphere of appropriateness for economic analogies of factory production, potentially undermining stewardship tendencies.

Furthermore, the term ‘ecosystem services’ is dead in the water as a tool for public communication. Polling clearly reveals such a widespread discomfort with ‘ecosystem services’ that The Nature Conservancy—one of the world’s biggest conservation NGOs—has revamped its communication to steer away from this term. But don’t get me wrong, I’m not taking issue with the ecological research enterprise focusing on ecosystem services: I’m a whole-hearted believer that we will foster improved decision-making through a better understanding of how ecosystem structures and processes relate to the things that we want and need. What I’m talking about here is how we verbalize these patterns of thought—and the overarching or undercutting way we present them to society, through the stories we tell.

What I’m railing against here isn’t the benefits part of ecosystem services (which is key), and it’s only partly the over-extension of economic production analogies. Mainly it’s the (unintended) association with a passive and expectant reception of benefits that reinforces the ‘me-first’ attitude and risks signaling acceptance of the notion that ecosystems are or ought to be organized first and foremost for those benefits. It’s a pattern of thought that is clearly reflected in the Economist’s 2005 irksome but memorable cover text and graphics for ecosystem services, “Are you being served?”

There’s a great logic to the notion of ecosystem services. We absolutely need to connect what we do to conserve ecosystems to the things that matter to people—clean water, productive soil, stable climate, and a host of less-quantifiable services. And dollar valuation can play an important role, sometimes. But since when did people only care about their passive reception of benefits? Behavioural psychology, cognitive science, and anthropology have demonstrated convincingly that economic assumptions characterizing people as rational utility-maximizers are inaccurate simplifications, albeit occasionally convenient ones. People care about caring—for people, homes, and landscapes—even when that caring comes with considerable cost and sacrifice. Parenthood made this easier for me to understand. About having a baby, fellow parents didn’t tell me, “You’ll love all the great things she’ll do for you!” They told me, “It’ll change your life forever, but it’s magical. I never knew I could love anything so deeply and completely.”

Of course I’m not going to promise anyone this kind of love of ecosystems, but I will promise fulfillment and a sense of belonging to anyone who strives to build a relationship with nature. People can be receptive to messages that don’t lead with a promise of benefits, but generally this requires a relationship—like the kinship relationship of many native peoples with nature. We can bring out caring tendencies in ourselves and in others if we do more to facilitate a sense of connection to nature. The literature on ecological restoration suggests strongly that getting people outside and actively participating in ecosystem care—especially with others—can help build the kind of ‘ecological citizenship’ that I think we seek (Light 2006). We can then link the caring of local ecosystems to (particular) more distant ecosystems, just as aid organizations so effectively hook people with pictures and stories of (particular) distant children, and from there we can build support for particular actions that benefit nature diffusely. Care begets care: I know how much more receptive I am to those messages now that I have two daughters. Social psychologists confirm this rule, having shown that engaging people’s self-interest serves to suppress their concern for others. So let’s encourage ecosystem-care for the fulfillment it provides through relationships, and also because it is crucial for humanity.

As an organizing principle for conservation and ecology, I’m now deeply suspicious of us-first ecosystem services and a firm believer in stewardship + life support systems. That’s not because my scientific understanding has changed, but rather because I find myself wanting to communicate with and partner with a broader cross-section of humanity. If we concentrate on the ways that ecosystems happen to fulfill our current preferences—labile and unpredictable as they are—we will miss the many opportunities that present themselves for us to grow into our roles as stewards, for us to fulfill ourselves not only through benefit-reception but through care.

Reference:
Light, A. 2006. Ecological Citizenship: The Democratic Promise of Restoration. Pages 169-182 in R. H. Platt, editor. The Humane Metropolis: People and Nature in the 21st-Century City. University of Massachusetts Press, Amherst, MA.

Triage Terror

Are conservation scientists ready to let endangered species blink out? Think again!

 

A New Scientist reporter writes: “Is it time to let some threatened species go extinct? The heretical notion is worthy of consideration, says a majority of conservationists contacted in a poll.” This survey, by Murray Rudd and published in Conservation Biology, found that a majority of conservation scientists agree that "Species and ecosystems are going to unravel so it is important that the conservation community considers criteria for triage decisions. If we don’t, ad hoc decisions could be even worse."

The term triage comes from war-time medicine, where a medic has to choose who will get their attention and likely survive versus who will be neglected and presumably perish. It involves three groups: those healthy enough not to need immediate medical attention; those who need immediate attention and could likely survive with it; and those who are close to death and from whom medical attention is withheld. The logic for this crucial cold-hearted third part of triage is that those most vulnerable would die despite efforts, and/or that efforts to save them would take away from time and resources to save others with a better chance. So conservation triage is the uncomfortable choice not to take action to save a population, species or ecosystem, knowing full well that withholding effort will likely lead to the extinction of that population or species, or to major changes in the ecosystem.

 
Are conservation scientists really ready to stop trying to save the more-endangered species because they're too far gone, as suggested by Rudd and the New Scientist? The survey actually suggests otherwise. A strong majority of the conservation scientists surveyed thought that the most vulnerable species should be the highest priority for conservation efforts: most agreed strongly that "the species with highest probabilities of extinction and ecosystems with highest probability of land-cover conversion should receive the highest levels of investment." That’s not cold-hearted triage, but its polar opposite.

Sure, many conservation scientists are willing to “consider criteria for triage decisions”, but apparently they’re not ready to cut their losses. They seem more than ready to do ER-type triage, where the more vulnerable are treated first, but no one is left out in the cold. And certainly, most are willing to recognize the finite nature of resources, and prioritize conservation efforts accordingly--but again, that's not triage in its controversial sense.

This controversy over triage is fundamentally a conflict between value systems: principles vs. ‘rational’ decision-making based on economics. We, along with many of our friends and colleagues, support biodiversity conservation largely out of principle, but of course we also favour rational decision-making. We generally believe that it's wrong that humanity should allow a species to go extinct. We don't necessarily believe that we should always save a species regardless of the cost, but we might believe that we should never give up.

Such a ‘heroic’ position is not unreasonable. It's perfectly legitimate to believe that as a society we ought to organize our activities to be life sustaining – for both humans and non-humans. We need creativity and innovation to meet human needs while preventing the extinctions of known species. We can reject any position that takes for granted the current structure or potential future trajectory of our economy. Costly expenditures on desperately-endangered species might be seen by some as a waste of money, but they can also be seen as a critical and appropriately expensive signal that our society is structured unsustainably.

This position does not conform to the prevailing 'rational' decision-making by which everything has its price. But for those who believe in sustainability, it’s perfectly rational.
Note furthermore, that in this case, the heroic position may actually be economically rational. Cold-hearted triage makes sense when resources are fixed (as with war-time medicine), but conservation resources are not fixed: they are a function of donors. And if donors are motivated at least partly by principle-based and heroic thinking, there are substantial risks to appearing cold-hearted and gains for those who attempt heroism. It’s unsurprising that conservation organizations have distanced themselves from cold-hearted triage thinking thus far.

We need conservation scientists and others to take informed, compassionate and, yes, heroic action to staunch species extinction.

~Kai Chan & Sarah Klain

A Sign of the Times

Not sure how I managed to miss this making the rounds on the internet, but here's a fantastic sign from Jon Stewart and Stephen Colbert's Rally to Restore Sanity as seen on the Owen Abroad Blog.

Why Rapture 2.0 was meant to fail, or why climate activists ride airplanes

By Jordan Tam

Soon after the predicted End, the vast majority of us were still here. Like déjà vu, the next predicted Armageddon (note December 21, 2012) is likely to unfold like yesterdays and those already passed. Perhaps this Rapture was another mathematical mistake (the given reason for the first botched Rapture of ‘94 provided by Mr. Camping, the failed prophet).

More predictable was the immediate response of those who believed the end was nigh. As a BBC article reports, some “...followers said the delay was a further test from God to persevere in their faith”. Cue sceptic and atheist eye-rolling.

However, are any of us innocent of this sort of rationalization?

Here we turn to a classic study in the annals of psychology by Leon Festinger and colleagues. In 1954, Festinger et al. managed to infiltrate a doomsday cult named the ‘Seekers’ led by one Mrs. ‘Marion Keech’. According to Mrs. Keech, who was purportedly able to transmit messages from aliens residing on planet Clarion, the End would come by way of a great flood on December 21, 1954. Non-believers would perish, but those who held their conviction would be saved and transported to safety aboard UFOs. Though Mrs. Keech had already falsely predicted several other End dates, it only served to strengthen her followers’ beliefs when the dates passed harmlessly. Indeed, as the morning of December 21^st dawned and none of the Seekers had been whisked away at midnight, the once insulated group began an uncharacteristic media blitz to promote their beliefs under the impression that God had spared humanity because of their strength of faith.

“Well Camping’s followers and the Seekers are nothing like me! They’re fanatics and I’m logical!” you might say to yourself. Read on...

Intrigued by the response of the Seekers to the failed prediction, Festinger took his study to the laboratory. In Festinger’s 1959 experiment, Stanford psychology undergraduates were asked to complete, with little instruction, two very boring tasks, namely “putting 12 spools onto a tray, emptying the tray, and refilling it with spools, and so on” for half an hour and then, on a board “containing 48 square pegs”, the participants were told to “turn each peg a quarter turn clockwise, then another quarter turn, and so on” using only one hand for half an hour.

Participants were then assigned to either: a control group who did nothing; a group in which the participant was paid a dollar to instruct the next waiting participant on the nature of the tasks and describe their experience doing the tasks as “very enjoyable, I had a lot of fun, I enjoyed myself....”; and another group who was asked to do the same for twenty dollars.

After lying through their teeth, the one dollar and twenty dollar groups, as well as the control group were asked to rate how interesting and enjoyable they found the spool and peg tasks on “a scale from -5 to +5 where -5 means they were extremely dull and boring, +5 means they were extremely interesting and enjoyable”.

The result?

While individuals in the control group unsurprisingly found the tasks boring, and the twenty dollar group found it a little less mind numbing, individuals who were paid a dollar somehow convinced themselves that organizing spools and turning pegs was exciting work!

The results illustrate a phenomenon known in psychology as cognitive dissonance. Cognitive dissonance theory predicts:

1) If a person is induced to do or say something which is contrary to his private opinion, there will be a tendency for him to change his opinion so as to bring it into correspondence with what he has done or said.

However, 2) the larger the pressure used to elicit the overt behaviour (beyond the minimum needed to elicit it) the weaker will be the above mentioned tendency.

In other words, twenty dollars was enough to pay for a lie but one dollar was barely sufficient, putting the one dollar liar in a strange situation. On the one hand they knew playing with pegs and spools was tedious yet had agreed to tell waiting participants it was fun and enjoyable for only a dollar. Clearly, they rationalized “I must have liked the task at least a little!”

...bringing us back to Seekers, the Rapture, and climate advocates. Often we act impulsively in ways that are incongruent with our internal beliefs and without anyone needing to pay us at all. And like Mr. Camping’s followers and Camping himself, we’re often forced to face contradictory evidence. In both these scenarios we are left with a sense of unease, motivating us to find ‘logical’ reasons why the Rapture failed to occur, or why it’s okay to fly around on airplanes for vacation even though we’re climate activists when we’re not on vacation. It’s not all that difficult to see how advocates for sustainable fisheries can indiscriminately gorge on sushi. Or why so many environmentalists just “needed” to buy their iPhone.

So while it’s easy to skewer and laugh at religious kooks, the conservation and environmental community would do well making case studies of their own behaviour, if only to better understand the challenges facing sustainability.

After all, people who live in glass houses shouldn’t throw stones.

Festinger, L., & Carlsmith, J. M. (1959). Cognitive consequences of forced compliance. The Journal of Abnormal and Social Psychology, 58(2), 203.

What's in a Number?

By Jordan Tam

A journey of a thousand miles begins with a single step. The size of that first step might matter a great deal if psychological research is any indicator.

As I write, Parks Canada is currently trying to protect Canada’s oceans through its National Marine Conservation Area (NMCA) initiative. We should celebrate this effort, but it’s worth asking if we’re jumping off the starting block with enough strength.

The southern islands of the majestic Haida Gwaii archipelago off the North coast of BC have recently come under NMCA protection. Only 3% of this conservation area, called Gwaii Haanas, has been designated as fully protected from commercial extractive use (e.g., commercial fishing). In last week’s Canadian Parks and Wilderness Society report, scientists recommended that 30% of all habitats – not just NMCAs—be protected.

Three percent might not sound like a lot, and that’s the point. A small first step might make it harder for us to get where we need to go.

If you’ve ever negotiated your salary and felt like you were being low-balled by an employer, you’ve likely experienced the well-known psychological bias of getting ‘stuck’ around this first number. This bias is known as ‘anchoring and adjustment’ and was first theorized by psychologists Amos Tversky and Daniel Kahneman (Tversky & Kahneman, 1974).

Just how powerful is this bias? Consider a fantastic experiment by behavioural economist Dan Ariely and colleagues (Ariely, Loewenstein & Prelec, 2006) in which individuals supplied the last two digits of their social security number. People were then asked whether they would be willing to pay the number of dollars equal to these two digits for a bottle of fine wine and to indicate the most they would actually pay. What they found was shocking: people who had social security numbers with the last two digits in between the range of 00 to 19 bid on average $8.64 while those with digits in the range of 80 to 99 bid an average of $27.91.

In other words, even arbitrary numbers can completely skew our judgment, usually without our awareness.

Three (percent) isn’t just a number. Like salary negotiations, negotiating for greater protection in Gwaii Haanas and other developing NMCAs may be slowed or stymied by setting the initial bar so low. We may get to 30% eventually, but having three percent ‘imprinted’ in our psyche, as Ariely puts it, may make take our journey the long way around. Focusing on the greater protection afforded the oceans through California’s network of marine protected areas and Australia’s Great Barrier Reef protection should be the standard to which we measure our progress.

Ariely, D., Loewenstein, G., & Prelec, D. (2006). Tom Sawyer and the construction of value. Journal of Economic Behavior & Organization, 60(1), 1-10. doi: 10.1016/j.jebo.2004.10.003

Tversky, A., & Kahneman, D. (1974). Judgment under Uncertainty: Heuristics and Biases. Science, 185(4157), 1124-1131. doi: 10.1126/science.185.4157.1124

Jesus, Zombies, and Other Deep Questions for Conservation

Gerald Singh and Ally Thompson

The May 21^st reckoning has been zealously touted by some, and ridiculed by others. We prefer to think that relevance can be found wherever you look.

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He must be pointing at a true believer (http://www.rcgroups.com).

We Hope You’re Ready.

Today is the rapture. While true believers are rejoicing their ascendency to heaven and nonbelievers are either recoiling in horror, indifferent, finding business opportunities, or making fun of the whole story (who would do such a thing?), we – as environmental and conservation scientists – have conflicting thoughts on the matter.

Jesus comes back today after a two thousand year absence. A series of earthquakes will open graves of those who died in the past (zombies? If true then things may go completely differently then outlined below). True believers (about 200 million) will be taken to heaven and the rest cast down in shame to remain on a doomed planet. Undoubtedly the whole ordeal will lead to civil and industrial strife for those left behind. And – here’s the kicker – everyone else dies and is cast down to hell on October 21.

This is serious (http://www.motifake.com).

On the one hand, this is an unprecedented opportunity for nature conservation. Depending on what happens to the wretches left behind on earth, the entire biosphere will have varying (though in any case lower) levels of human impact. All other organisms not being made in the image of God will be spared the messiness of heaven and hell. With remaining humans dealing with issues of basic survival and infrastructure nonexistent, pressure on wildlife through pollution, introduction of exotic species and diseases and habitat degradation will probably go down (though hunting may increase with less certain food supplies). The entire ocean will effectively be put under one big Marine Protected Area. No more illegal trade for endangered animal parts. No more industrial carbon emissions. No more housing and industrial development leading to edge effects. All three components of Paul Ehrlich’s equation for human impact on the environment (Impact = Population × Affluence × Technology) will go down. With less dependency on technology and more so directly on the natural environment, will the value of ecosystem services increase?

Now that's a protected area (http://interesting-facts.info).

On the other hand, what happens after the five month period of a Godless World (something that isn’t clear to us) raises some problematic metaphysical and metaethical concerns. If existence itself is destroyed, nature – by definition – is also destroyed. However, if just people get cast down to hell and the world remains, that raises the truly interesting questions. If nature goes back to a pristine state but there is no one left to appreciate it, does it matter? Can you have value without a valuer? Because “pristine” necessitates the absence of humans, is this truly a desirable goal for conservation? Besides these fundamental concerns about the existence of intrinsic values, the other issue is that the world will lose those interactions between people and nature that are worth conserving. The ties to nature and deep sense of place that local fishers, farmers, and others that derive their well-being and livelihoods will be gone. Humans have helped shape the world that we admire, and human loss will lead to a very different place: it will be a return from a socio-ecological system to an ecological system.

Wait. We'll lose this?!?!

A Short (Serious) Digression on Prediction

The human attraction to eschatological stories is an interesting one. For one, it affects the religious and non-religious alike. Stories of biblical Armageddon are widespread, but works by scientists like James Lovelock and Paul and Anne Ehrlich also discuss “end-times” situations. Both sides may not have their most extreme predictions come through, but the scientists in this case have some evidence and insights worth considering (such as overpopulations contributing to increased starvation). The problem is that the evidence-lacking, religious “authorities” get more press, more followers, and more impact. There are countless stories to be found covering the “rapture” predictions, and people seriously believe it. These stories do affect people’s views and actions, and this has important implications for conservation. Why should any care or concern be put to environmental concerns when the world is ending soon anyway? Can this kind of mindset be successfully challenged and changed? Conservation is a real world problem with diverse issues to face. Many of the most pressing issues relate to human behavior. What can conservationists learn from doomsayers?

Marine Protected Areas—Reality Check from Scientists

In a report released today by the Canadian Parks and Wilderness Society (CPAWS), fourteen leading Canadian researchers and CPAWS staff sent a sharp reality check to government officials working on the protection of ocean and Great Lake ecosystems, simultaneously shining a beacon of hope.

In brief, current marine protection efforts fall far short—shockingly short—of what is likely needed to achieve what Canada has sought in various laws that enable the creation of marine protected areas (MPAs). On the flip side, it is possible to design, implement, and manage networks of MPAs to achieve great benefits for marine ecosystems, potentially restoring a bounty of nature that has disappeared from the memories of all but a handful of seasoned salty dogs.

Falling short

The protection of ocean ecosystems in MPAs is far short of the protection of terrestrial ecosystems globally, and marine protection in Canada lags well behind marine protection in numerous other countries. Less than 1% of Canada’s ocean territory is protected in MPAs [1], whereas approximately 12% of the Earth’s land surface is under some form of protection. Even more stark is the contrast with what seems to be needed to achieve the objectives and benefits of MPAs: my colleagues and I have recommended that at least 30% of Canada’s waters should be strictly protected in order to have a high likelihood of success [2]. (By strictly protected, we mean without extractive uses, except constitutionally protected First Nation food, social and ceremonial harvest.)

There’s no doubt that this high target for protection will invite substantial push-back, particularly from ocean users, as to the realism of ‘setting aside’ so much productive space. To such charges, I have three responses. First, the 30% minimum is a statement of the science of what’s necessary for particular outcomes sought by laws and policies on the books, not a statement of preferred policy. Some of our recommendations would likely require new laws and policies to support the existing ones (the Oceans Act, the National Marine Conservation Areas Act), but it is not the place of scientists to modify science-based targets in the name of political feasibility [3].

Second, MPAs aren’t ‘set aside’ in the sense of being locked up without production. MPAs are hard at work producing diverse benefits for people, both within and beyond their boundaries.

The Big Eddy, a high-productivity site that CPAWS has
advocated to be protected, off the west coast of
Vancouver Island.

Third, humans adapt. We have only just begin to think seriously about marine protection, and such big challenges typically seem impossible until they are started with conviction.

Beyond the proportion of the seascape that we recommended for protection, we have also recommended substantial changes to the processes of designing, implementing, managing, and governing MPAs. For example, we’ve underlined the critical importance of embedding MPAs in seascapes that are managed with an ecosystem-based approach, accounting for the cumulative impacts of multiple human activities on ecosystems and the services they provide people (see the Sidney Consensus for a multi-stakeholder consensus on the meaning of ‘ecosystem-based management’ (EBM) for western Canada) [4]. This is critical for MPAs because patches of ocean are not islands—they are intimately connected to surrounding seascapes, in ways that both make them vulnerable and also allow export of the benefits they provide, including fish, shellfish, and other organisms.

A second critical process we’re recommending as necessary for MPAs—paralleling the Sidney Consensus regarding EBM—is adaptive management: designing policies and management explicitly for the sake of learning, in order to improve future management. Current management is generally not adaptive in this strong sense, but it must be in order to disentangle the cobweb of interacting impacts on marine ecosystems: commercial, recreational, and subsistence fisheries, warming, acidification, pollution from both land-based and marine activities, sedimentation and erosion from coastal development, etc. It’s clear that adaptive management requires a major shift in mindset, but it’s also clear that without a structured adaptive approach, management is flying blind.

What’s new?

In recommending 30% as a minimum area for strict protection, our team is keeping with past recommendations, such as from the University of Queensland in Australia [5], and from a team of scientists regarding the California Channel Islands [6]. It's also in keeping with the actual percent protected in the Great Barrier Reef. But this is also a leading edge recommendation, because it rests upon an extensive review of the science in support of areal targets for marine protection.

The yellow areas in this map are high-priority areas
for MPAs, according to the BC Marine Conservation
Analysis. Well under 1% is currently under strict
protection.

Although the numbers are not exact, the available evidence strongly suggests that the benefits of marine protection will often not be fully realized unless at least 30% of the ocean is strictly protected. And these studies generally consider a small number of well-studied impacts on ecosystems, whereas we know that marine ecosystems are threatened by a wide variety of impacts, many of which are very poorly studied. Similarly, the existing studies generally consider a simplified set of the ecological processes—like migration—that sustain populations and ecosystems. Recognizing that there is always a suite of impacts and multiple essential ecological processes that might be degraded by those impacts, arguments for less than 30% protection are simply not supported by current science.

The hope

Our message is at its heart a hopeful one. Marine ecosystems are invisible to most of us, even though we benefit greatly from them in the form of seafood, climate regulation, cultural values and more. As invisible common property, ocean ecosystems have been subject to no end of insults over the past few decades, without eyes to see the resulting devastation. The implication is that the oceans that you see now are a pale shadow of the oceans that once graced this planet, and a meager version of what is possible. Numerous studies of marine populations in many ecosystems suggest that historical levels of abundance were manifold greater than current levels [7,8]. Such bountiful abundance is not beyond our reach unless it is also beyond our imagination. Restoring ocean ecosystems is no easy task, but a robust network of MPAs is a superb first step towards that end. And the payoff could be immense.

1. Jessen S (2011) A Review of Canada's Implementation of the Oceans Act since 1997: From Leader to Follower? Coastal Management 39: 20 - 56.

2. Jessen S, Chan K, Côté I, Dearden P, Santo ED, et al. (2011) Science-based Guidelines for MPAs and MPA Networks in Canada. Vancouver: Canadian Parks and Wilderness Society. 58 p.

3. Tear TH, Kareiva P, Angermeier PL, Comer P, Czech B, et al. (2005) How much is enough? The recurrent problem of setting measurable objectives in conservation. Bioscience 55: 835-849.

4. Chamberlain J, Chan K, Coleman H, Diggon S, Edwards D, et al. (2010) The Sidney Consensus.

5. University of Queensland Ecology Centre (UQ EC) (2009) Scientific Principles for Design of Marine Protected Areas in Australia: A Guidance Statement. Brisbane: University of Queensland Ecology Centre.

6. Airamé S, Dugan JE, Lafferty KD, Leslie H, McArdle DA, et al. (2003) Applying ecological criteria to marine reserve design: A case study from the California Channel Islands. Ecological Applications 13: 170-184.

7. Jackson JBC, Kirby MX, Berger WH, Bjorndal KA, Botsford LW, et al. (2001) Historical overfishing and the recent collapse of coastal ecosystems. Science 293: 629-638.

8. Jackson JBC (2006) When ecological pyramids were upside down. In: Estes JA, editor. Whales, whaling, and ocean ecosystems. Berkeley: Univ of California Press. pp. 27-37.