Sunday, July 30, 2006

How Do Spider Webs Get Started?

When I walk through the woods in the morning, the trail is filled with spider webs, many, disturbingly, at face height. In some places the trail is four feet wide between closest branches on either side. So my question is, how did the spider get the first line across the trail, in order to build the web? I don't believe a spider can jump four feet through the air. Do they attach a line to a branch then walk into the tree trunk, down the tree, across the ground, up the other tree trunk, to the same height as they were? All the while they would be spooling out silk and not getting it tangled on anything? I don't think that's feasible. The weight of the silk line would be too much to haul up the second tree anyway. Maybe the spider throws or shoots the first line across the trail. But I don't think spiders can do that. Another possibility is that the spider fastens a line high up on one branch and then swings like Tarzan across the trail to a branch on the other side. That seems improbable, but it could be right. I wonder if they beat their little spider chest with eight tiny fists as they swing from the silk line, and even let out a spider-sized "aah-eee-aaah!" as they make the trip.

Monday, July 24, 2006

Inconvenient Consequences of Global Warming

We’re all aware of what can happen if global warming continues: melting ice caps, rising sea levels, flooded (or submerged) cities around the world (including my own!).

Some of the less obvious changes will be (and are already), different mix of species, with extinction of some, migration of others. As ecologists know, the relationships are complex. If a predator can’t make it because it gets too warm, its prey species will balloon out of control. And it will probably be insects!

Likewise, if a food source like plankton diminishes because the water is too warm or too cold, the ripples go all the way up the food chain to us.

Agriculture will move farther north and south away from the equator. Canada’s Yukon Territory will be the breadbasket of North America, not the Kansas desert. Political and economic power will move with the agriculture.

One of the most disturbing possibilities is that the electrical grids of industrialized nations will completely fail. They are already wobbly, and with the stresses of future extremes of heat and cold, it will collapse. We don’t appreciate how much we depend on the electrical grid in every action of our lives until the power goes out for a day or two.

There will be no heat or air conditioning, of course, which makes everybody cranky. No computers or internet either, which would not merely be a throwback to 1980’s communication, because printing presses wouldn’t work until they got hooked up to expensive, petroleum-dependent generators. Scholarly and pop culture communication would rely only on expensive printed material, as it did from the seventeenth century up to about 1980. The computer industry would be kaput.

TV and radio would cease to function. On the upside, we wouldn’t have to listen to the lies of politicians and advertisers. Of course the media could get generators, but there would be few customers able to receive their product. So that would be the end of that industry, too. It might be a relief. Traveling snake oil salesmen are much easier to avoid than ubiquitous ads.

However, without mass media, the public stories we tell each other to maintain social cohesion would be lost and the country would devolve into isolated villages or regions. Maybe that wouldn’t be a bad thing, socially, but the loss of economic transparency would raise all prices painfully. Inevitably, isolated regions would develop unique cultures and predictable xenophobia. Secessions and wars would follow after only a few generations.

We will go to the market every day because there will be no refrigeration for food beyond ice. That will change the way food is produced, stored, and sold. It will change our diets. We will spend more time raising and preparing food and less time reading, writing, and racing dirt bikes. And when we’re not preparing food, we’ll be heating water and washing clothes by hand. But it would be a good time to get into the ice business.

There will be an unsustainable run on wax candles and batteries. But on the plus side, most of us will finally find relief from chronic sleep deprivation. And instead of CDs and movies, we will seek out live musicians and theatrical troupes.

Would the electrical grid be repaired? Of course. Despite the nostalgic charms of a non-electrified world, most of us enjoy the modern world too much to go back to that. People will pay any price to restore the grid. But hopefully, in doing that, we will think twice about how we generate and use electricity, perhaps making some wiser decisions the next time around.