Davies claims that life’s defining characteristics are better understood in terms of information. This is not as absurd as it may seem. Energy is abstract, yet we have little trouble accepting it as a causal factor. Indeed, energy and information are closely related through entropy.
He thinks that instead of looking for chemical signatures of life elsewhere in the universe, we should be looking for informational signatures.
What practical difference does it make to see life as informational? We don’t yet know, but can speculate. For one thing, if the essential characteristics of life are entropic, extraterrestrial searches based on chemistry could be misguided. It might be more useful to look for phenomena such as ‘anti-accretion’ — in which matter is regularly transferred from a planet’s surface into space. Earth has experienced this since the 1950s, when the one-way traffic in asteroids and meteorites plunging into the globe was finally counteracted by the launch of the first artificial satellites. Arguably, such situations are not merely consistent with the presence of life, but almost impossible to explain in any other way. Timo Hanay, “Maxwell’s demon and the hunt for alien life” at Nature
The problem with taking information seriously in the evolution of life, as in Introduction to Evolutionary Informatics, is that it may rule out favorite “evolution” claims. Taking it seriously and discounting it whenever it matters is a fancy dance.