Biomass

Since the rise of human civilization,  life forms larger than 10 centimeters to a metre have been systematically culled or eliminated from the ecosystem.  Almost all land megafauna that used to roam wildly a few thousand or even hundred years ago are either extinct or reside in small numbers in protected parks and reserves. Macroscopic sized sea creatures that were reasonably plentiful just two or three decades ago may all disappear shortly.  In that mean time the population of  humans and domesticated plants and animals have exploded.

So, has there been a net gain or loss of total biomass?   I think the conventional wisdom would be that we have replaced large tracts of forest with pavement, lawns and farmland, which would seem like a huge net loss of biomass.  However, we have added extra nutrients (i.e. fertilizer) and carbon (i.e. fossil fuels) into the system. The energy flux from the sun has also not changed significantly in the last millennium.  Hence, the capacity to support life has probably not changed or maybe has even increased. Removing, all of the large wild animals may also create more opportunities for small animals.  Perhaps there are more small and microscopic creatures then there would have been had humans not existed.  I have no idea what the answer is.

Paulos in the Times

Mathematician John Allen Paulos, author of Innumeracy and other popular books on math, has a beautifully written column in the New York Times.  He articulates a dichotomy, which most people probably have never thought of,  between stories and statistics.  Here is a small excerpt from the article:

Despite the naturalness of these notions, however, there is a tension between stories and statistics, and one under-appreciated contrast between them is simply the mindset with which we approach them. In listening to stories we tend to suspend disbelief in order to be entertained, whereas in evaluating statistics we generally have an opposite inclination to suspend belief in order not to be beguiled. A drily named distinction from formal statistics is relevant: we’re said to commit a Type I error when we observe something that is not really there and a Type II error when we fail to observe something that is there. There is no way to always avoid both types, and we have different error thresholds in different endeavors, but the type of error people feel more comfortable may be telling. It gives some indication of their intellectual personality type, on which side of the two cultures (or maybe two coutures) divide they’re most comfortable.

People who love to be entertained and beguiled or who particularly wish to avoid making a Type II error might be more apt to prefer stories to statistics. Those who don’t particularly like being entertained or beguiled or who fear the prospect of making a Type I error might be more apt to prefer statistics to stories. The distinction is not unrelated to that between those (61.389% of us) who view numbers in a story as providing rhetorical decoration and those who view them as providing clarifying information.

I highly recommend reading the whole article.

 

The Genographic Project

National Geographic is conducting a research project (The Genographic Project) to analyze historical genome patterns  by sampling DNA from people all over the world. The main aim is to sample from various indigenous peoples from around the world but the public can participate as well. The website for the project is here.  There is a charge for a participation kit, which is used to defray the costs of the study.  You can have your mitochondrial DNA, which follows your maternal lineage, or if you are a male, the Y-chromosome, which follows your paternal line analyzed.  I  recently did the test for my Y-chromosome and I am a member of Haplogroup O with the M175 marker.  My earliest male ancestor emerged roughly 50,000 years ago in Africa and is the common ancestor of every non-African male alive today.  The man with the M175 marker emerged about 35,000 years ago during the ice age somewhere in Central or East Asia.  There were probably something like 100,000 Homo sapiens alive at that time.

On tunnels and civilizations

One of the recurring themes in my posts is that seemingly irrational or self-defeating behavior has an underlying logic.  There are always trade offs, so if one behavior or tendency allows us to succeed in some aspect then it may impede in some other.  Paul Krugman laments in today’s New York Times the demise of a second rail tunnel between New Jersey and New York.  He’s been voicing his frustrations about our inability to make the correct choices to move forward for the past few years.  Below is a post I wrote in 2005 that gives my argument for why civilizations have finite life spans.  I think it is still relevant today.

Scientific Clearing House Sep 22, 2005:

Every time I feel kind of optimistic about the future, I think back to the Roman Empire and realize that it could all end pretty quickly. It may be no accident that civilizations tend to have finite lives and our brains may be responsible. Jared Diamond (in his book Collapse) posits a framework for a society’s demise but he basically believes it is some combination of bad decision making and management that leads to failure. I’m proposing that it may actually be embedded in how our brains work and how it reacts to success. What allows us to build great civilizations may ultimately be responsible for our undoing.

As has been written in countless columns and blogs, manufacturing, software development, clerical work and so forth is being or will soon be outsourced to an offshore location where labour costs are so much lower. Many have argued that the US can retain world dominance by remaining a source of innovation and ideas. However, Thomas Friedman and others have been screaming lately that the US is losing it’s lead in technology and science and American students are falling behind the rest of the world in technical subjects.

The reason is not just that we’ve become lazy or stupid. The Flynn effect shows that average IQ’s have actually been rising every generation and in the recent book Everything Bad is Good For You: How Today’s Popular Culture Is Actually Making Us Smarter, Steven Johnson argues that video games and popular culture are actually making us smarter. So why is it that we are becoming less intellectual even though we are getting smarter?

I think it is related to the fact that it takes effort to concentrate on something. This effort is not because we’re using more energy. Although it may seem that thinking hard burns more calories, there is in fact little evidence for this. So if there is no metabolic cost then why is it so difficult to think? The reason may be that the brain is a novelty machine that constantly seeks new stimuli. Advertising and marketing people know that they need to change a scene every 10 or 15 seconds in a commercial or people’s attention will be lost. Our brains are designed to wander and seek new stimuli. This constant novelty seeking probably helps in the early stages of a civilization where things need to be built and everyone sees open opportunities for growth.

As a civilization matures, it takes longer and longer for the citizens to acquire and digest the accumulated knowledge required just to keep it running much less advance it. Years of training is necessary before anyone can make a contribution. Given our current comfortable circumstances, there is little incentive to undertake such an ordeal when there are so many other distractions to occupy us. In the past, scholastic learning might have been the most cognitively stimulating thing one could engage in. Now, our lives are filled with leisure activities that are much more interesting and entertaining than what we learn in school. For every high school kid with his nose stuck in an analysis textbook, there are hundreds or thousands of other kids who are playing video games, surfing the web, reading a Harry Potter novel or solving a Sudoku puzzle.

Is there a way out? I’m pessimistic. While it is true that those on the cutting edge are doing very interesting and stimulating things, the journey to get there is so long and arduous that fewer and fewer are likely to take it. No matter how appealing you may make calculus or organic chemistry, they just will never be able to compete with the endless variety of distractions in modern society. There will still be an educated elite but there won’t be enough of them to keep the engine going.

The decline of the US could be very rapid. Even now, much of science and technology is being driven by foreigners. However, as the balance of power starts to shift overseas and the US remains xenophobic, that spigot could be shut off quickly. The incentive to come here will diminish and people may return to their native countries as things decline here accelerating the process.

It may be that the only hope for humanity is to maintain uneven economic development. If the entire world became comfortable simultaneously, it might completely collapse all at once. However, if the decline of the US is accompanied by the rise of China and India then at least some order in the world could be maintained. After a century or so, the US could rise again in a perpetual cycle of localized growth and decay.

Scotch tape and flying frogs

This year’s Nobel prize in physics went to Andre Geim and Konstantin Novoselov for making single layer graphite or graphene using scotch tape.  However, Geim is also famous for having won an Ignoble prize for demonstrating diamagnetic levitation using a frog.  You can see a video of a flying frog and tomato here.  Sir Michael Berry of Berry’s phase fame and Geim wrote a paper demonstrating that diamagnetic but not paramagnetic objects can be levitated stably in a solenoidal magnetic field.  This was somewhat surprising because there is a theorem (Earnshaw’s theorem) that says you cannot suspend an object with fixed charges and magnets in any combination of static, magnetic, and gravitational fields.  The reason diamagnetic levitation works is because Earnshaw’s theorem does not apply to induced magnetism.