Caching is a standard solution to the problem of insufcient bandwidth caused by the rapid increase of information circulation across the Internet. Cache consistency mechanisms are a crucial component of each cache scheme in uencing the cache usefulness and reliability. This paper presents a model for optimizing Internet cache content by the use of a genetic algorithm and examines the model by trace-driven experiments. Cached data are considered as a population evolving over simulated time by a number of successive cache \generations". The model is tested by the use of traces provided by a Squid proxy cache server. Using trace-driven caching, we show that the proposed evolutionary mechanisms improve cache nonstaleness and consistency and result in an updated cache content.