The Natural Patriot

Egad, it’s been a month again. Just thought I’d drop a note to let concerned readers know that I am indeed still alive. For the last two weeks, I’ve been pedal-to-the-metal doing field research in the Caribbean, around the island of Curacao in the Netherlands Antilles to be specific (the previous three weeks, and for that matter the last several months, require a more prosaic excuse, with which I will not bore you). For some reason, it’s always very difficult to convince people that I have been working my you-know-what off on a tropical island. They invariably jump to the conclusion that we’re sitting around drinking fruity drinks with little umbrellas in them. Which is not true at all — we never use those little umbrellas. I do realize that this does not qualify me for hardship pay. Hence the title of this post.

Don’t misunderstand me — I’m not complaining. If you’re going to be working somewhere, a tropical island is a favorable place to do it. Our team was on Curacao as part of a research project, supported by the National Geographic Society, studying the ecology and biogeography of symbiotic Caribbean shrimp, which I have alluded to before. This may sound a bit obscure (OK, it is obscure) but we argue that the high diversity and clearly definable habitats of these shrimp, which inhabit living coral-reef sponges, makes them an ideal group for studying general questions about the origin and maintenance of coral-reef biodiversity. And, since the Carmabi Research Station where we set up shop is surrounded by hotel beaches and tiki bars, we got a lot of practice honing this argument for the constant stream of mildly amused random passers-by who were wondering what on earth we were doing so intently while they lay all day in a state of sun-and umbrella-drink-induced torpor. I hope I don’t sound like an ingrate.

So (as the old explorers’ tales go): there we were. Very interesting place, Curacao. Quite different than anywhere else I’ve been in the Caribbean. Looks more like Texas. I’m told that the name Curacao derives from a Portugese term that translates roughly as “wasteland”. And it surely must have seemed so to exhausted 16th century sailors looking for decent food, water, and precious metals. The island is very arid, with a negligible layer of debris that passes for soil covering the limestone rock and supporting a burnt-looking vegetation of vicious thorn scrub (Acacia of some sort) and saguaro-like cacti. Not much good for anything other than goats. And lizards of several sorts, which are ubiquitous. Those enterprising colonialists did manage to find a use for the place as a hub of the slave trade, which they would no doubt be happy to forget. Nowadays, however, it’s a bustling place with a population of 150,000 people supported mainly by the massive oil refinery that processes the fruits of Venezuela’s wells a few miles away on the South American mainland.

For our specific purposes it was an equally interesting place. Great diving: clear water, and lots of the magic coral rubble that produces shrimp, in relatively shallow water. Indeed, the reef at Eastpunt, at the windward eastern end of the island removed from much human influence, had without a doubt the highest coral cover and diversity of any place I’ve seen in the Caribbean in the last few decades. Easily 80-90% cover of live coral. And small but healthy thickets of the formerly dominant shallow-water Caribbean corals Acropora cervicornis and Acropora palmata, which have long since succumbed to disease and various other stresses elsewhere. Very strange — like a visit several decades back in time. A rare and much valued ray of hope in a bleak outlook for Caribbean reefs. It is a tremendous relief to know that these reefs exist at least somewhere. Hope springs eternal.

To be continued . . .

The National Wildlife Federation has just released an important new report “Sea-Level Rise and Coastal Habitats of the Chesapeake Bay“, which provides the most detailed and comprehensive view yet of the likely impacts of climate change on specific habitats within the Chesapeake Bay region. The full report , as well as a 12-page summary are available here.

Among the highlghts:

“Coastal habitats in the Chesapeake Bay region will be dramatically altered if sea levels rise globally about two feet by the end of the century, which is at the low end of what is predicted if global warming pollution remains unaddressed. Under this scenario, the region would lose:

• More than 167,000 acres of undeveloped dry land
• 58% of beaches along ocean coasts
• 69% of estuarine beaches along the bay
• 161,000 acres of brackish marsh
• More than half of the region’s important tidal swamp

These important wetland habitats would be replaced in part by over 266,000 acres (415.6 square miles) of newly open water and 50,000 acres of saltmarsh.”

I participated in the press conference to summarize the likely effects on wildlife and ecosystems of the Chesapeake Bay. The story was reported by the Baltimore Sun, the Richmond Times-Dispatch, and the Daily Press, among others.

Here are the points I made:

There’s now strong international consensus among scientists that climate change is real, and already happening. But most previous research has focused on very broad continental scales. The new report by the NWF is important because it shows in unprecedented detail how climate change is affecting our local Chesapeake Bay region.

The bottom line is that this is not a future threat. Rising temperatures and sea levels are already changing distributions, life cycles, and interactions of key animals and plants in our area. And those changes are disrupting important ecosystem services that coastal communities depend on—fisheries, water quality, shoreline protection.

The life cycles of animals and plants are closely tied to temperature, which determines when they emerge from dormant stages, reproduce, start seasonal migrations, and so on. For example, recruitment of commercially important fish and shellfish is highly sensitive to variation in both temperature and rainfall patterns. Springtime in the Chesapeake is starting about three weeks earlier now than it did in 1960. And the summers are getting hotter. In the Chesapeake, we may be in danger of losing more northerly species such as winter flounder and softshell clams.

One serious concern involves how changing climate affects “foundation species”, that is, key species that support entire ecosystems. One of these is eelgrass, an underwater plant that forms dense meadows throughout Chesapeake Bay and is a critical nursery habitat for young fish and shellfish, including blue crabs, rockfish, and speckled trout, among others.

Eelgrass is highly vulnerable to climate change, first because it’s near the southern end of its distribution in the Bay and thus already near the highest temperatures it can tolerate, and second because it’s already stressed from poor water quality. We got a preview of this in summer 2005 when we had record high water temperatures throughout the mid-Atlantic region. Eelgrass was wiped out in a matter of weeks from large areas of the Bay, and still hasn’t returned to some.

A few more hot summers like 2005 could give eelgrass the one-two punch that knocks it out for good. That would be bad for the animals it supports and for the coastal communities that depend on them.

Another set of threatened foundation species are the plants that support wetlands such as brackish marshes. These are important in literally holding the land together by trapping sediments to make soil. Roughly two thirds of the Chesapeake region’s commercial fishes depend on coastal marshes for nursery and spawning grounds, and these are highly sensitive to both habitat quality and climate.

Chesapeake wetlands have been declining fast in recent decades. The classic example is the Blackwater National Wildlife Refuge in Maryland, which has been called the “Everglades of the North” because of its great abundance and diversity of wildlife, including the largest population of bald eagles north of Florida.

Blackwater illustrates well how climate change interacts with other stresses. Over the last seventy years, it’s lost a third of its marsh area to sea level rise, sinking of the land, and overgrazing by nutria, an alien rodent. The nutria is currently kept from spreading north largely by its intolerance of cold winters, and there’s real concern that it could spread as winters warm.

Finally, an important impact of climate change is that it alters interactions between species that respond differently to changes, with important implications for food chains and ecosystems. One important case involves the oyster disease Dermo, which proliferates in warmer waters. Starting in the mid-1980s, Dermo spread rapidly up the East Coast from Chesapeake Bay during a series of unusually mild winters and is now found up through Maine, with major consequences for the oyster industry.

These changes have fundamental consequences for coastal ecosystems, economies, and ways of life.

Over the last few weeks, while piddling around the project site (i.e., yard), pulling weeds, attempting to ferret out the invaders from the natives, puzzling over bugs, and pondering where I might site a small pond (and how to sell the idea to my spouse), I’ve had occasion to dust off my venerable Golden Nature Guides, beloved little books of childhood.

For me, there are few physical objects that can conjure the idyllic, big wide world of childhood gone by than these wonderful little gems of natural history. They were frequent companions for me as a youngster and I still take them out with a certain reverence to look through the pages, one for each species, each a marvel of textual and pictorial concision, with a short description of the creature’s habits and natural history, a map of its distribution, and a simple but beautiful painting of it in its characteristic habitat. These books somehow hit on the perfect formula for conveying the beauty and fascination of living things to kids.

And we owe it all to a guy named Herbert S. Zim.

Not exactly a household name. But if you still have a dog-eared copy of one of the dozens of Golden Nature Guides that were eventually published over the decades starting in 1949, you will notice that virtually all of them were written, co-written, or edited by Herbert S. Zim. His curriculum vitae, in brief, from Wikipedia:

“Zim was born 1909 in New York City, but spent his childhood years in southern California. At the age of fourteen he returned to the east, and took his degrees (B.S., M.S., Ph. D.) at Columbia University. Zim wrote or edited more than one hundred scientific books, and in a thirty-year career teaching in the public schools, introduced laboratory instruction into elementary school science. He is best known as the founder, in 1945 (and for twenty-five years, editor in chief) of the Golden Guides, pocket-size introductions for children to such subjects as fossils, zoology, microscopy, rocks and minerals, codes and secret writings, trees, wildflowers, dinosaurs, navigation and more. He was the sole or co-author for many of the books, which were valued for their clarity, accuracy and attractive presentation—helped by the illustrations of his friend, Raymond Perlman.”

Consider the impact that this single unsung man (so unsung, in fact, that the pixelated snapshot above is the only one I could find of him online!) has had on the environmental awareness of an entire generation — perhaps even two or three generations — of American citizens. Who can say how many kids in the 50s and 60s and 70s decided, while browsing through one of these little books, to spend the afternoon outside hunting for caterpillars instead of yielding to the seductive stupor of the cathode ray tube? Who can say how many of today’s alternative energy entrepeneurs and scientists and educators and conservationists caught fire as a result of a spark generated by one of these books? I can’t, but I know one: me.

By way of illustration, three personal anecdotes:

When I was a kid, my family drove cross-country (in a van without air-conditioning that was prone to overheating in the desert and climbed the Rockies at about 18 mph, etc.), from Arlington, Virginia to LA, every three years, where we spent the bulk of three weeks visiting my aunt and her family. When I tell people this they think my parents were crazy. But it was a the adventure of a lifetime and an incomparable learning experience for kids. We saw a lot of the country, did a lot of camping, and my parents occasionally allowed us to visit the cheesy fake Indian trinket shops that were common along the dustier stretches of Route 66 in the olden days. One day when I was probably about seven (this would have been the late 1960s), we were visiting Walnut Canyon, which is somewhere in the southwest, and I convinced my parents to buy me the Golden Nature Guide to Rocks and Minerals. I felt so grown up to have a real book instead of a kid’s book. It was an early watershed moment in my life as a bookworm and naturalist.

Nevertheless, I was not destined to be a geologist. For one thing, rocks are dead. Or so they seemed to me. I found animals much more interesting. Second anecdote: Around the same time, in second grade, I became obsessed with turtles. I take this herpetophilia to be a common, though poorly understood, genetic trait located somewhere on the Y chromosome, since it is so commonly expressed among young boys. This is despite the fact that my white-bread suburban neighborhood turned out, to my dismay, to be nearly devoid of reptiles. I saw maybe two or three box turtles, and no snakes at all, in the wild while I was growing up despite frequent expeditions mounted for that purpose to the local park where I spent much of my youth. But I can remember sitting rapt with the pocket-sized Golden Guide to Reptiles and Amphibians, studying the pictures, memorizing what they ate, looking at the ingenious maps that showed purple where the summer (pink) and winter (blue) ranges overlapped. This genetic propensity has in fact been transferred to my son, who latched on to my antique Reptile guide in an uncannily similar way and spent a lot of time with it (it is now bound with duct tape).

Anecdote three: One of the standard operating procedures of the cross-country trips was that, periodically, we would take a rest stop and every kid (of which there were ultimately six, though we never made the trip as a complete group) got to choose a magazine or coloring book or something to keep them quiet for 6 or 8 minutes after we hit the road again. On this trip, I think I was about ten and, instead of getting the standard Mad magazine or puzzles or comic book, I chose the Golden Nature Guide to Birds. Paging though that book as we droned along the highway, through southern Canada if I remember correctly, was the first time I actually noticed that birds (and other animals) had distinguishing marks that could be used to identify them. Perhaps the first tentative roots of my later interest in taxonomy.

It appears that I’m not the only one with such fond memories. Evidently the original versions of the Guides have recently become “collectible“. Many have since been reprinted, albeit without the engaging covers of old, and are available from St. Martin’s Press.

Now then: I was appalled to read, as I was surfing the web in search of intel on Dr. Zim, that the famous PZ Myers of Pharyngula fame had disparaged the gentleman’s name — simply because as a lad PZ lost a library copy of Zim’s Golden Guide to Mammals and got into deep doo-doo with the librarian. Even today, these decades later, the Golden Guides have traumatic associations for him.

Note to PZ: Dude, Herb didn’t lose your book — you did! Suck it up.

So I am here to clear the man’s name. Let us lift a glass to the late great Herbert S. Zim, pioneer of biophilia and Natural Patriot: we salute you.

OK, not exactly live – It’s a day after the fact.  But who would have paid attention if this read: Yesterday from EarthFest!

Yesterday I participated in EarthFest 2008, sponsored jointly by NASA Langley and Christopher Newport University here in Tidewater, Virginia.  I was part of the “Ask a scientist” panel, answering questions from the brave-hearted studio audience of about 20 people who had forsaken the fabulous spring weather to sit in a darkened lecture hall and ask questions such as these of scientists.

And a shout-out to the VIMS Green Team and the Williamsburg Climate Action Network, among the many other organizations represented there.  I’m told that parts of our panel discussion will evntually be posted in YouTube - stay tuned.

Following is the text of the two-minute presentation with which I began my part:

Locally, for you or I standing here on the ground, life is not a thin green film. It’s a fantastic variety of plants and animals and microbes that have become linked in complex networks of interactions that we call an ecosystem.   

We usually take the ecosystems around us for granted because we are so much a part of them that we don’t even think about it.  But we need to. 

Ecosystems are like nature’s factories. Living organisms provide the natural infrastructure that creates natural products and services essential to our comfort and even our survival—food, clean water and air, favorable habitat in which we can live, and of course the stable climate that we hear so much about these days.

We’re now at a critical turning point in earth’s history.  For the first time in the 3.8 billion years of life’s tenure on this planet, a single species literally controls the fate of all the others, and of the biosphere itself.  That species is of course us.  It’s a mind-boggling responsibility. 

And — sad to say — we’re dropping the ball. When we dump our wastes into the air and water, when we destroy natural habitat, and harvest animals faster than they can reproduce, we are throwing a monkey wrench into the gears of Nature’s factory and its parts get broken.When that happens the machine stops working, and the products and services disappear. 

But that doesn’t have to happen.  Humans are incredibly ingenious.  We’ve sent people to the moon.  We’ve invented the internet, and cars that run on french fry oil.  We need to harness that ingenuity to make the world safe again for our fellow creatures.  Because, in the end, we literally cannot live without them.”
 

Now that’s what I’m talkin’ about!

See also here to get involved. The US House of Representatives’ Education and Labor Committee is currently considering the No Child Left Behind Act (summary of the Act here, complete text here), which would promote environmental literacy and education integrated into an environmental context (as shown in the video).  Write your Congressperson and help raise the next generation of Natural Patriots!

Interesting editorial in Nature today. It details a phenomenon that, sadly, is characteristic of this administration, thankfully now a lame duck.  I quote the editorial in full:

The EPA’s tailspin

The director of the Environmental Protection Agency is sabotaging both himself and his agency.

The US Environmental Protection Agency (EPA) is fast losing the few shreds of credibility it has left. The Bush administration has always shown more zeal in protecting business interests than the environment. But the agency’s current administrator, Stephen Johnson, a veteran EPA toxicologist who was promoted to the top slot in 2005, has done so with reckless disregard for law, science or the agency’s own rules — or, it seems, the anguished protests of his own subordinates.

On 27 February, to take the first of two examples that surfaced last week, Senator Barbara Boxer (Democrat, California) used a routine budget hearing to give Johnson a grilling. Why hadn’t he given her state permission to regulate the carbon dioxide emissions of vehicle exhausts? California needs a waiver from the EPA to regulate in this way, and in the past such waivers have been granted easily. And, Boxer reminded him via a series of leaked memos and PowerPoint presentations, Johnson’s own top-level staff begged him to sign the waiver in this case. “This is a choice only you can make,” one colleague wrote to him. “But I ask you to think about the history and the future of the agency in making it. If you are asked to deny this waiver, I fear the credibility of the agency that we both love will be irreparably damaged.”

In December, Johnson announced he would refuse the waiver, an act that would also deny permission to more than a dozen other states seeking to base their exhaust regulations on California’s. Johnson argued that climate change is not a local phenomenon, so dealing with it isn’t what the authors of the Clean Air Act intended for the waiver system.

Although logical, this argument is similar to that made by Johnson’s EPA in an earlier case involving Massachusetts, when the agency fought against CO2 regulation all the way to the Supreme Court — and lost. His insistence on using it again can perhaps best be understood from the fact that Johnson answers to a White House that is hostile to regulation on principle. It is also worth noting that his refusal documentation, made official on 29 February, extensively quotes an industry trade association, the Alliance of Automobile Manufacturers.

The second example came on 29 February, in the form of a joint letter to Johnson from the four labour unions representing most of the EPA’s professional staff. Listing examples of alleged bad faith by Johnson, the unions essentially refused to work with him until he cleans up his act. Among the complaints was an assertion that he repeatedly ignored the EPA’s official Principles of Scientific Integrity, citing “fluoride drinking water standards, organophosphate pesticide registration, control of mercury emissions from power plants” — and the waiver refusal.

In a rational world, Johnson would resign in favour of someone who could at least feign an interest in the environment. Alas, it seems that he will probably stay on until January 2009, refusing waivers, fighting lawsuits and further depressing employees’ morale. In the meantime, we can only offer those employees a fantasy: the White House doesn’t want the agency to do anything, so shut it down until next January. Take some fully paid sabbatical time to relax, and prepare for a return to the old-fashioned protecting of the environment that so many of you joined the agency for.

Ten months left now . . .

I suppose we should have known it was all too good to be true.  What could be wrong with using plants for fuel?  They take carbon out of the air, so burning them up in the tank just puts it back up there — no net change, right?

Wrong.

We’ve already heard about the massive quantities of synthetic fertilizer and water required to keep a biofuel crop like corn going.  And there is the distinctly distasteful problem that the corn would do a lot more good feeding someone.  Indeed, the headlong rush into converting cropland to biofuel cultivation is already raising food prices.

As if that weren’t bad enough, it turns out that even where the major biofuels would seem to have a hands-down advantage over petroleum, i.e., on the balance sheet for net carbon emissions, the story is quite a bit less rosy than it appears.

A new study by Fargione et al in Science has crunched the numbers to show why. The key advance here is that these authors calculated the amount of carbon present in both the standing biomass (i.e., trees) and in the underlying soils on the land that is cleared for biofuel crops.  They then estimated how much of that carbon is released into the atmosphere, and over how long a time span, by burning or microbial decomposition in exposed soil.  It turns out that a large quantity of carbon is lost gradually from the soil over the course of decades after land has been cleared.  Fargione and colleagues call this the “carbon debt” from land conversion:

“Over time, biofuels from converted land can repay this carbon debt if their production and combustion have net [greenhouse gas, GHG] emissions that are less than the life-cycle emissions of the fossil fuels they displace. Until the carbon debt is repaid, biofuels from converted lands have greater GHG impacts than those of the fossil fuels they displace.”

Greater GHG impacts than petroleum. The figure below shows the numbers for several major types of biofuel operations hat involve land conversion. 

The figure shows for each of nine scenarios (A) the carbon debt, i.e., the CO2 emissions from soils and biomass lost or degraded during habitat conversion, (B)  the percentage of that debt due to biofuel production as opposed to other uses, (C) the annual carbon repayment rate, meaning the greenhouse gas reduction from fossil fuel use displaced by the biofuel production, as well as carbon storage in soils, and — here’s the kicker — (D) the number of years required to repay biofuel carbon debt.   The results are, to put it mildly, sobering.  For example, conversion of native grassland (if you could find some) to cornfields for ethanol production requires 93 years to break even.  In Indonesia and Malaysia, where vast swaths of virgin rainforest are being burned down every year to plant oil palms, it would take four centuries to repay the debt. As the authors note: 

“Our analyses suggest that biofuels, if produced on converted land, could, for long periods of time, be much greater net emitters of greenhouse gases than the fossil fuels that they typically displace. All but two—sugarcane ethanol and soybean biodiesel on Cerrado—would generate greater GHG emissions for at least half a century, with several forms of biofuel production from land conversion doing so for centuries. At least for current or developing biofuel technologies, any strategy to reduce GHG emissions that causes land conversion from native ecosystems to cropland is likely to be counter-productive.”

Now, lest I be accused (again) of being pessimistic, there is some good news of sorts here if you hunt for it.  The main point is that not all biofuels are created equal. As I’ve discussed before, you can avoid the carbon debt by brewing fuel from plants growing on land that is too degraded to produce much of anything else, or from harvesting of natural prairie vegetation that does not require the land clearing that sends all that wood and humus and soil carbon up in smoke.  Doing that on a commercial scale is of course not as straightforward as growing corn or soybeans, but these data emphasize that it is well worth exploring.

Maybe that way we can minimize the hot air.

[Source: Fargione, J., J. Hill, D. Tilman, S. Polasky, and P. Hawthorne. 2008. Land Clearing and the Biofuel Carbon Debt. Science 319: 1235 - 1238.]

Tired of sifting through the virtual world for interesting stuff?

Blog carnivals in two pleasing, environmentally friendly colors are now online. Get your blue at Kate Wing’s blog, host this time around of the tenth monthly Carnival of the Blue, which covers the waterfront as the saying goes . . .

 . . . and your green at Confessions of a Closet Environmentalist, this week’s host (they’re a bit ahead of us above the tide line). Good stuff at both venues.

As the evidence for ongoing climate change has grown incontrovertible, there is increasing urgency to the question of what these changes hold in store for us.  Some wondered why Al Gore and the IPCC should be awarded the Nobel peace prize for promoting climate science?  Is there really a connection?  One source of insight involves querying the past: what consequences have past climate changes had for human society? 

In a relatively new study (published in December 2007 — I’m a little behind the curve here), David Zhang and colleagues exploit new high-resolution paleo-temperature records to address this question. The paper assembles evidence from five to ten centuries of human history to show that climate variation drives changing food production, which among animals typically results in what we ecologists call “intraspecific competition”, that is, competition among members of the same species.  Among humans we call it war.

The Figure at left shows the northern hemisphere temperature variation (as anomalies from the long-term average, panel A), war frequency, and rate of change in human population from 1400 to approximately the beginning of the industrial revolution in 1900. The number of wars is shown for the northern hemisphere as a whole (bright green line, and right axis scale), Asia (pink), Europe (turquoise), and arid areas of the northern hemisphere (orange). Panel C shows number of wars worldwide as recorded by three different authors using different thresholds for defining war — as can be seen, the trends are roughly similar. Finally, panel D shows the 20-year population growth rate in Europe (turquoise), Asia (pink), and the northern hemisphere as a whole (blue), as well as the 50-year fatality index in the region (bright green). Cold phases of history are shaded in gray. The bright green curves correspond to the right axis. 

What to make of all this?  First, we can see that climate varied during this time between cool and warmer periods that lasted decades to a few centuries. More importantly, these cool and warm periods coincided with times of unrest and relative tranquility, respectively.  Considering the whole global data base, there is a strongly significant negative correlation between war and temperature, with temperature anomaly explaining 28% of the variation in war frequency.  Even more telling, this “rhythm of history” was roughly synchronous across the northern hemisphere. Since, during these centuries, China and Europe were still largely isolated from one another, the synchrony of these trends over such an area, comprising much of the northern half of the planet, is difficult to explain by any factor other than the clear signal of large-scale global climate. 

The relationships are even more pronounced in the finer-resolution record for China during the longer period from AD 1000 - 1900 (see figure below): here each of the cool periods (gray shading) saw a major spike in the number of wars.

The figure at right summarizes in diagrammatic form the pathways by which long-term climate variation influenced frequency of war and human population dynamics in China and Europe during preindustrial times (i.e. up to 1900). Solid lines indicate direct effects, and dotted lines indirect feedbacks. Thicker arrows indicates stronger correlations.  There are several inrerrelated impacts of climate change mediated by the interactions of humans with our food supply and with each other, but food supply is central. 

So, OK, this data comes from back when people rode horses and peasants grubbed for potatos all winter long and so forth.  Why should we care in the 21st century?  We have refigerators and grocery stores!  Besides, the climate now is warming, rather than cooling, so it should all be good, right?  The most general message for us today is that climate variation has profound impacts on the global ecosystem’s ability to provide vital services, which in turn have profound implications for human society and well-being.  Although a warming climate has been good for us in the past, and will surely be good for some people in some places in coming decades too, we are facing a much bigger and faster warming than the earth has seen in a very long time.  And one of the consequences is change in rainfall, which is an even more powerful regulator of agricultural productivity than temperature.  And when food runs low, conflict is inevitable, as we are seeing in Darfur.  Too little (crop)land to go around was evidently a key match to the flame in Rwanda during the 1990s also.

Scholars have long sought, with only partial success, to explain the conflicts that repeatedly plague civilization. The results of this paper indicate that human ecology is –- or was — forced to a surprising degree by the same basic environmental drivers and by similar, if more destructive, mechanisms of competition that regulate populations of other animals.

There is hopeful news too. We have learned a thing or two in the last millennium.  As the authors note:

“In the long run and at a global scale, technological and social development raised the population growth rate . . . reduced climate dependence of growth rate of population (after A.D. 1400), postponed the time of population decrease, and accelerated subsequent population recovery . . . The gradual increase in time delays for [northern hemisphere] population declines as we moved into the modern era may reflect that at least some social mechanismsmay becoming more effective over time at the macroscale.”

At the same time:

“these adaptive choices that are positive to humanity have not let the human race escape from social calamities such as population collapse caused by severe cooling at both the global and continental scales as shown in the history of the past millennium. For armed conflict, the positive social mechanisms could neither reduce the number of wars nor indefinitely postpone the times of war outbreak in any cooling periods . . . Although we have more robust social institutions at both international and national levels, and much more advanced social and technological developments at present, a much larger population size, higher standard of living, and more strictly controlled political boundaries will limit some adaptive choices to climate change. We hope that positive social mechanisms that are conducive to human adaptability will play an ever more effective role in meeting the challenges of the future.”

[Original source (open access): Zhang, D.D., P. Brecke, H.F. Lee, Y.-Q. He, and J. Zhang. 2007. Global climate change, war, and population decline in recent human history.  Proceedings of the National Academy of Sciences of the USA 104:19214-19219.]

[The painting shows the English victory over the French at the battle of Agincourt in 1415.] 

Top ten list - Excellent!

I am honored to have received the Excellent blog award, bestowed after a rigorous screening and review process, and accompanied by a handsome prize consisting of the right to display proudly a small jpeg image on my website (see below left, and in the sidebar).

The honor was bestowed by the venerable Coturnix (aka Bora Zivkovic) at “A blog around the clock“.  For those less familiar with the minutiae of blog history, Bora is a pioneer of science blogging.  His multifarious accomplishments include (1) serving as the Online Community Manager at PLoS-ONE (Public Library of Science), the rapidly growing open-access biology journal that encourages online commentary; (2) conceiving the idea for, and editing, the inaugural two issues of “The Open Laboratory: The Best Science Writing on Blogs“, which have been made available to Luddites in old-fashioned paper format, available here; (3) co-organizing the (first?) North Carolina Science Blogging Conference, which drew a large number of premier science bloggers , journalists, scientists, and educators from around North America, and which I will definitely want to attend next time around.    

An honor such as this comes with responsibility of course.  And in the characteristic pyramid-scheme modus operandi of the blogosphere, mine is to finger ten more blogs that I deem “excellent!”  I am of course delighted to do so.  Thus, in no particular order:

Growth is madness. It’s the economy, stupid.  And the people (yes, us) that keep cranking it upward.

Trinifar. More than food for thought - a feast for thought.

The other 95%.  Wide-ranging essays, musings, and news related to the bizarre and multifarious creatures that populate our earth.

Church of the Flying Spaghetti Monster.  Amen brothers and sisters!

The Beagle Project.  A clever premise, which provides scaffolding for some interesting discussion.

Earth Forum.  More than just a blog — it’s an encyclopedia too!

Framing science.  And politics, etc.  The power of words, for good and ill.

Environmental economics.  WWA (Wonks with attitude). Actually makes economics interesting.

Children and Nature Network.  OK, I cheated — it’s not a blog.  But I love what these guys are about and what they’re doing.

Blogfish.  One of my early inspirations in blogging. A pioneer at the interface of marine science, conservation, and outreach.

There you have it.  Tag — you’re it!