Future Darwinism- Towards an Information-based Theory of Evolution

The core of the Darwinian evolutionary process is the capacity of an organism to adapt to its environment. Living systems that adapt best are therefore more likely to survive and continue to adapt through ongoing recombination, mutation and replication.

But how do organisms know how to adjust to the optimum level of adaptation required by their environment? What is the process in the complex chain of cellular processing events that triggers the level of adjustment needed- for example to cope with a new food source or an increase in temperature?

The transmission of information from the environment to the organism, say in the form of a chemical signal, obviously plays a critical role in the process.

However we are more used to thinking about evolution in terms of natural selection for a wide range of physical traits. The idea that selection could depend on the level of information sensed about the state of the environment, takes us to a much deeper and more radical level.

Any organism, even as basic as a bacterium, that embodies some knowledge about its environment, is in a better position to exploit environmental resources and optimize its growth potential.

Each bacterium uses lac proteins to break down its food- the sugar lactose. Knowing how much lac protein it should produce to maximise its use of the available sugar in its environment provides it with a competitive edge over rival cells.

In recent experiments at Princeton University, physicist Professor William Bialek and his team provided the evidence for this critical link between life’s evolution and its capacity to access and interpret the information in its external environment, using the single cell bacterium E.coli as a test model.

Too much or too little protein production harms the organism's survival prospects. A bacterium that can calculate how much lac protein to produce to utilise available sugar in its environment will gain a survival advantage.
He calculated that bacteria storing one bit of information about production of the lac protein in their gene regulatory network, gives the cell the capacity to turn production of one protein on or off, which in turn provides a 5 per cent "fitness advantage" over bacteria storing no bits.
This suggests that there is an "information minimum" for life’s survival and that natural selection favours organisms that capture more bits of information about their environment.
This is a hugely significant finding, providing direct evidence to support the thesis that the process of evolution and adaptation is governed by the level of access to relevant information in an organism’s environment; and that this principle is common to all living systems.

It therefore provides a critical link in the chain of evidence supporting an ultimate information-based Theory of Evolution.