Living things need to know what conditions are like in the outside world so they can adapt to their environment. Is there food, light, heat out there and if so, where. So a certain amount of information must flow into the organism.
This information flow is crucial–without it life could not exist so it’s reasonable to assume that evolution must have selected organisms on the basis of their ability to handle this flow. But how could you prove this?
Samuel Taylar at Princteon University and a few pals have examined this idea in detail and discovered that in single celled organisms “the minimum information required for reasonable growth rates is close to the maximum information that can be conveyed through biologically realistic regulatory mechanisms“.
Case closed.
Ref: arxiv.org/abs/0712.4382: Information and Fitness