Tuesday, December 01, 2009

Hedging the bets

Cover description, Nature, 5 November: "The cover shows colonies of the bacterium Pseudomonas fluorescens that have evolved the capacity to switch randomly between colony types, enabling them to thrive in a fluctuating artificial environment that constantly favors different colonies. This laboratory demonstration of the evolution of 'bet hedging' illustrates a strategy that may have been among the earliest evolutionary solutions to life in fluctuating environments."

It's a dicey world
we live in. War.
Swine flu. Global warming.
The "greatest economic crisis
since the Great Depression."
The guy in the coffee shop
going postal.

                        So
we hedge our bets, buy
health insurance, keep a gun
in the bedside table, money
under the mattress, extra canned food
in the pantry. You never know
about these fluctuating
artificial environments that favor
different ways of getting by.

It's an old story, four billion
years old at least. Our one-celled
ancestors hedged their bets,
always prepared to pull
the old switcheroo, a cache
of useful phenotypes
tucked in the genome, money
under the mattress, so to speak.

Even the lowly bacterium
Pseudomonas fluorescens,
initially comfy in its comfy world,
quickly learns de novo
in the lab to hedge its bets
when subjected to a challenging
new environment -- climate change
of a sort.

                An evolutionary lesson,
I suppose, as we debate
health care, carbon caps,
energy independence, military
escalation: It's always good
to have a stash of alternate strategies
up one's sleeve.