Fitness Landscapes are Upside Down

Posted by | January 15, 2009 | half baked ideas | No Comments

Chris Nedin writes about the analogy of evolution in a fitness landscape where fitness equates to climbing a mountain, and recommends turning the fitness landscape upside down:

“Adaptation is not climbing up Mt Improbable, it’s climbing down Pit Improbable! The pits are hard to find, but once in, it’s easier to go down than it is to back out, and if you adapt too far, you are trapped in a cul-de-sac with no way out when the environment changes.”

Although this makes sense, the very fact that we can flip the landscape shows that evolution requires a proper explanation in terms of physics, where the ‘pits’ are, perhaps, energy wells determined by the relationship between evolution and entropy.

The fitness landscape is a visual tool to help us understand eco-systems, rather like the rubber sheet visualization of gravity in General Relativity. Neither the geometry of space-time or fitness landscapes are actually stretchy 2D sheets in 3D space. But like gravity, which exists in curved 4D space, there may be a real geometry of evolutionary fitness landscapes.

The equivalent of ‘matter tells Spacetime how to curve, and Spacetime tells matter how to move’, would be something like:

‘organisms tell the fitness landscape how to curve and the fitness landscape tells organisms how to adapt’.

In that phrasing the fitness pits work best.

Now if only we knew the dimensions, let alone the geometry.

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