August 24, 2010

The struggle for existence

Thomas Malthus, 1766-1834.

I've been musing off and on here lately about Charles Darwin and the legacy of his thought. If you like that kind of thing, check out some of last week's posts.

As Darwin began to build his theory of evolution, he struggled for some time with finding the mechanism that might drive it. He found a clue in reading Thomas Malthus' An Essay on the Principle of Population, which incidentally became very popular amongst Victorian era reactionaries who opposed any improvement in the condition of the working classes.

Malthus' basic idea was that production of food and other necessities could only increase arithmetically (think 2+2+2...), whereas population tended to increase geometrically (think 2*2*2...). As he put it,

I think I may fairly make two postulata. First, That food is necessary to the existence of man. Secondly, That the passion between the sexes is necessary and will remain nearly in its present state. These two laws, ever since we have had any knowledge of mankind, appear to have been fixed laws of our nature, and, as we have not hitherto seen any alteration in them, we have no right to conclude that they will ever cease to be what they now are...

Assuming then my postulata as granted, I say, that the power of population is indefinitely greater than the power in the earth to produce subsistence for man. Population, when unchecked, increases in a geometrical ratio.

(Malthus' ideas caused all kinds of political mischief, but I'll leave that for another day.)

For Darwin, the basic dynamic Malthus discussed was useful in looking at the evolution of species. The tendency of plants and animals to produce more offspring than could possibly be supported led to a "struggle for existence" with which natural selection could work. Given that struggle, those organisms best adapted to environmental challenges would be more likely to live to maturity and produce offspring.

As the saying goes, even a wild hog can dig up something useful sometimes. More on Malthus to come.

INTOLERANCE. Here's a photo essay on intolerance in America by way of Time Magazine.

SOLAR ENERGY might be getting more affordable soon.

CRY, CRY, CRY. It seems to serve an evolutionary purpose.

MOUNTAINTOP REMOVAL is the topic of this NY Times editorial. I don't think they're for it.

THE GROWING GAP. America's widening class divide is the subject of this Gazette rant.


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