Travel Reference
In-Depth Information
Turning people into hoatzins
We humans, unlike the proboscis monkeys, can easily adapt to new food-
stuf s because of our evolutionary history as an omnivore. But there are
limits to our own adaptation, at least in the short term. To illustrate this,
let us explore an all-too-plausible near future in which our population has
increased to the point at which we have irreversibly damaged our planet,
reducing the amount of food on which we all depend. Could we save our-
selves by taking advantage of cellulose, the immense food source that pro-
boscis monkeys thrive on but that is completely unavailable to us? What
kinds of evolutionary change would that new ability require?
Let us begin with the food potential of cellulose. As of this writing the
Sunday edition of the
New York Times
has slimmed considerably, but before
the newspaper business tanked and news junkies decamped to cyberspace
this great mass of newsprint weighed about two kilograms. Much of the
paper's bulk was made up of ads touting quaintly antediluvian mechanical
wristwatches, at prices that could retire the national debt of a smallish coun-
try. But interspersed among these ads was all the news that's fi t to print. If
you lingered abed each Sunday and read the paper thoroughly, you would be
sure to become almost pathologically well informed.
But then you had to get rid of that great mass of paper. At the moment the
best way is to recycle it. A third of the four billion trees cut down worldwide
each year are made into paper, and more ei cient recycling could reduce
this number substantially. Luckily, the habit of paper recycling is growing
dramatically in the USA, and currently more than 50% of the paper in the
country is salvaged and recycled. But the rest ends up in landfi lls, or as ash
and carbon dioxide. And recycling is strongly dependent on the world econ-
omy, so that the fi nancial payof for recycling goes up when our economy is
healthy and goes down when the economy is sick.
Suppose that, instead of recycling the paper, you could eat it? The
New
York Times
is made of fi bers of cellulose, and as we saw earlier the cellulose in
turn is made up of long strings of the nourishing sugar glucose. Luckily for
the newspaper's food potential, the process of paper-making has removed
