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My latest Mind and Matter column in the Wall
Street Journal is about the role of disease in species
Some beekeepers, worried by the collapse of their bee colonies
in recent years, are pointing a finger this month at a class of
insecticide (neo-nicotinoids) that they think is responsible for
lowering the insects' resistance to disease. They may be right, but
I'm cautious. History shows that, again and again, blaming
chemicals for the decline of a species has prematurely exonerated
the real culprit, which is often disease alone.
The role of parasites in causing species to decline is often
overlooked. Native European red squirrels, for example, have long
been retreating in Britain at the hands of the American gray
squirrel, which menagerie-owning aristocrats introduced in the 19th
century. For years it was thought to be the competition for food
that prevented the squirrels' co-existence, but now scientists
place most of the blame on a parapox virus that causes a mild
illness to the grays but kills the reds.
My latest Mind and Matter column for the Wall Street Journal is on
Human beings, we tend to think, are at the mercy of their genes.
You either have blue eyes or you do not (barring contact lenses);
no amount of therapy can change it. But genes are at the mercy of
us, too. From minute to minute, they switch on and off (i.e., are
actively used as recipes to make proteins) in the brain, the immune
system or the skin in response to experience. Sunbathing, for
example, triggers the expression of genes for the pigment
As a recent study confirms, on a much longer time
scale, genes are even at the mercy of culture. The paradigmatic
example is lactose tolerance. All mammals can digest lactose sugars
in milk as babies, but the lactase gene switches off at weaning
when no longer needed. In much of Europe and parts of Africa, by
contrast, most people can digest lactose even as adults, because
the lactase gene remains switched on. (About 90% of East Asians and
70% of South Indians are lactose-intolerant to some degree.)
One of my favourite writers these days is Willis Eschenbach,
whose essays at wattsupwiththat often combine ingenious scientific
rationality with lyrical prose. Here he is on the subject of the
sea ice off Alaska:
My point in this post? Awe, mostly, at the damaging power of cold.
As a seaman, cold holds many more terrors than heat. When enough
ice builds up on a boat's superstructure, it rolls over and men
die. The sun can't do that. The Titanic wasn't sunk by a heat
The thing about ice? You can't do a dang thing about it. You can't
blow up a glacier, or an ice sheet like you see in the Bering Sea
above. You can't melt it. The biggest, most powerful icebreaker
can't break through more than a few feet of it. When the ice moves
in, the game is over.
My latest Mind and Matter column in the Wall Street
Even a rational optimist is pessimistic about some things. Here's
one: the gradual distortion of the human sex ratio by sex-selective
abortion. A new essay by the demographer Nicholas Eberstadt
concludes that "the practice has become so ruthlessly routine in
many contemporary societies that it has impacted their very
population structures." He finds "ample room for cautious
pessimism" in the fact that this phenomenon is still very much on
For obscure reasons, the human sex ratio is always slightly
male-biased, but in the natural state it rarely goes above 105 male
births per 100 female ones, except in small samples. In China's
last mini-census in 2005, the ratio was nearly 120 to 100 and in
some districts over 150. That this is caused by sex-selective
abortion (and not, for example, by a hepatitis-B epidemic, which
can favor male births) is proved by a ratio of 107 to 100 among
first-born children but nearer 150 among ones born later.
China is not the only country where this is happening. By the
early 21st century, all four Asian "tigers"-South Korea, Singapore,
Hong Kong and Taiwan-had a "naturally impossible" ratio of 108 or
higher. India has an increasing ratio, as high as 120 in some
states. Even some European and central Asian countries (including
Albania, Georgia and even Italy) have unnaturally male-biased
births. Nearly half the world falls in this category.
Each year, John Brockman's website, The Edge, asks a question
and gets many answers to it. This year, the question is: What is
your favourite deep, elegant, or beautiful explanation? Some of the
answers are fascinating. Here's mine:
It's hard now to recall just how mysterious life was on the
morning of 28 February 1953 and just how much that had changed by
lunchtime. Look back at all the answers to the question "what is
life?" from before that and you get a taste of just how we, as a
species, floundered. Life consisted of three-dimensional objects of
specificity and complexity (mainly proteins). And it copied itself
with accuracy. How?
How do you set about making a copy of a three-dimensional
object? How to do you grow it and develop it in a predictable way?
This is the one scientific question where absolutely nobody came
close to guessing the answer. Erwin Schrodinger had a stab, but
fell back on quantum mechanics, which was irrelevant. True, he used
the phrase "aperiodic crystal" and if you are generous you can see
that as a prediction of a linear code, but I think that's
Here's my latest Mind and Matter column in the Wall Street
Journal, with added links and charts. On interglacials.
The entire 10,000-year history of civilization has happened in an
unusually warm interlude in the Earth's recent history. Over the
past million years, it has been as warm as this or warmer for less
than 10% of the time, during 11 brief episodes known as
interglacial periods. One theory holds that agriculture and dense
settlement were impossible in the volatile, generally dry and
carbon-dioxide-starved climates of the ice age, when crop plants
would have grown more slowly and unpredictably even in warmer
This warm spell is already 11,600 years old, and it must surely,
in the normal course of things, come to an end. In the early 1970s,
after two decades of slight cooling, many scientists were convinced
that the moment was at hand. They were "increasingly apprehensive,
for the weather aberrations they are studying may be the harbinger
of another ice age," said Time in 1974. The "almost unanimous" view
of meteorologists was that the cooling trend would "reduce
agricultural productivity for the rest of the century," and "the
resulting famines could be catastrophic," said Newsweek in
Since then, of course, warmth has returned, probably driven at
least partly by man-made carbon-dioxide emissions. A new paper,
from universities in Cambridge, London and Florida, drew headlines
last week for arguing that these emissions may avert the return of
the ice age. Less noticed was the fact that the authors, by analogy
with a previous warm spell 780,000 years ago that's a "dead ringer"
for our own, expect the next ice age to start "within about 1,500
years." Hardly the day after tomorrow.
My latest Mind and Matter column in the Wall Street
Coral reefs around the world are suffering badly from overfishing
and various forms of pollution. Yet many experts argue that the
greatest threat to them is the acidification of the oceans from the
dissolving of man-made carbon dioxide emissions.
The effect of acidification, according to J.E.N. Veron, an
Australian coral scientist, will be "nothing less than
catastrophic.... What were once thriving coral gardens that
supported the greatest biodiversity of the marine realm will become
red-black bacterial slime, and they will stay that way."
This is a common view. The Natural Resources Defense Council has
called ocean acidification "the scariest environmental problem
you've never heard of."
My Mind and Matter column for the Wall Street Journal on 1
January 2012 is here:
Here's a New Year's thought. With some nine million species on
the planet, and with each species lasting a million years on
average, about nine species will go extinct naturally this coming
year (with more, almost certainly, going extinct unnaturally). But
about nine new species also will be born in 2012.