Coruscant - an ecumenopolis

What are sci-fi movies trying to tell us with images, and themes, like the above? The term ecumenopolis comes from the combination of the two Greek words ecumene and polis -- in other words, a city made of the whole world. It is featured in Star Wars (as an example) as the planet of Coruscant (pictured above). Watching the movie one may note that there is no visible greenery on the planet, no visible water, and even major landscapes are dwarfed or have been wiped out by buildings. It is a theme that has been mentioned numerous times in science fiction, and a listing can be found in Wikipedia. While it seems like a thing of fantasy, the view of North America from space at night suggests otherwise (see below).

An ecumenopolis in the making?

My thoughts turned to such notions as I was reading the following article, which is definitely worthy of a read. The article discusses the issue of mesopredator release, which is when small- to mid-sized predators are released from the pressures of their own predation by large-sized predators. Since they are no longer prey, they are allowed to feast on their own prey, often bringing those populations crashing down.

In canyons with coyotes, a greater diversity of birds survived. Canyons without coyotes supported fewer species. Having seen ample evidence that coyotes were responsible for his disappearing pets—cats flying through the cat door as if “chased by the devil”— Soulé had a theory: more coyotes meant fewer cats. Fewer cats meant more birds. Coyotes were eating not only cats but also other midsized predators, such as foxes. Coyotes were acting as a control. Without that control, the midsized carnivores ran wild in an orgy of predation that Soulé termed “mesopredator release.” Another study confirmed it: one in five coyote scats contained domestic cat.

How does this happen? Well, unsurprisingly, we're to blame.

As scientists study the unbalanced and fragmented systems humans create as they alter the environment, they are realizing how interdependent species are. In a way, all of us are now living in a scientific experiment similar to that which San Diego developers created by carving up the canyons. We have unleashed forces we are still struggling to comprehend.

We've created these fragmented ecosystems through urbanization. The simple act of building, and paving roads, can fragment an ecosystem. It also does incredible damage to the wildlife, as any honest assessment of the roadkill you may pass on a daily basis is a testament. And things are only going to get worse.

Biodiversity loss is now lining up to be the greatest man-made crisis the world has ever known. Biologists call it the Sixth Great Extinction, or the Holocene extinction event, after our current geologic time period.

Oh come on, is it really going to be that drastic? You bet it is.

Preeminent biologist E. O. Wilson believes we stand to lose half of all species by the end of this century.

Half of all species! It is not as if all these species are going to be wiped off the planet by the same method. Some will be driven to extinction because of the above-mentioned meso-predation, but others will be hunted to extinction. Yet others will be left to die-off because we've isolated their habitat to such an extent that inbreeding will increase their susceptibility to diseases which will eradicate them. Bringing invasive species to virgin ecosystems (these species find themselves with no predators in their new environs) will kill off yet other species. A look in the United States alone shows many invasive species -- pythons which are ravaging the Everglades, Asian carp which are now threatening the Great Lakes, kudzu taking over (PDF, 8 pages) the Southern United States -- the list goes on and on -- which are devastating ecosystems.

We are aware of many species which are endangered. What we have not fully come to grasp with (though we know a good deal on the subject) is how this inter-relatedness will ultimately affect our planet. Richard Conniff wrote a very good opinion piece in Yale Environment 360 entitled What Are Species Worth? Putting a Price in Biodiversity. In this piece he provides several examples of the need for biodiversity, but the story of the vulture is the most telling.

So in India in the early 1990s, farmers began using the anti-inflammatory drug diclofenac for the apparently worthy purpose of relieving pain and fever in their livestock. Unfortunately, vultures scavenging on livestock carcasses accumulated large quantities of the drug and promptly died of renal failure. Over a 14-year period, populations of three vulture species plummeted by between 96.8 and 99.9 percent.

No big deal right? Just a bunch of vultures. Au contraire, as Conniff explains.

Moving into the niche vacated by the vultures, feral dog populations boomed by up to 9 million animals over the same period. Dog bites and the incidence of rabies in humans also increased, and the authors conservatively estimated that an additional 48,000 people died during the 14-year period as a result. Calculating the bottom-line worth of what we get from the natural world is notoriously difficult. But even pricing lives at a fraction of developed world values, the near-total loss of three insignificant vulture species has so far cost India an estimated $24 billion.

That's more than just a drop in the bucket.

As a microbiologist who deals with microbial community structure and diversity I know first hand how these communities can interact, supply, and support one another. Some species are capable of forming flocs which serve as a scaffold for other organisms. In turn these organisms provide nutrients that the other species may like to feed upon but cannot make on their own. Yet other organisms are capable of producing enzymes which degrade environmental toxins which can damage the rest of the community. This synergism, which cannot be seen with the naked eye, mimics the world which we move about in. Each species has filled a niche, they do their job and we take them for granted, that is, until they are gone ... like the vultures in India.