Digital life broadens our conception of life, and is a useful tool for some kinds of biological studies. Digital life has some unique properties that make it easier to study than organic life. Because it is inside the computer to begin with, it is much easier to obtain data about digital life. In fact, when digital organisms are confined to a single computer, it is possible to collect data about any aspect of their existence without affecting the system. This is impossible with real organisms. For example, it is a routine matter to sequence the entire genome of every digital organism at birth, and this sampling has no effect on the evolution of the system.
Also, digital AL systems can be easily manipulated to an extent not possible with real life, and if desired, an experiment can be exactly repeated, in order to make observations that were not made in the original run. In addition, some life processes, such as evolution, can proceed much more quickly in the digital than in the organic system.
These properties combine to make digital life a valuable addition to the field of biology. One area where this has been most fruitful has been evolutionary studies. Like a chemostat full of evolving bacteria and viruses, a computer full of evolving digital organisms could be thought of as a model system for the experimental study of evolution. However, the evolving digital organisms are no more a simulation of evolution than are the evolving bacteria and viruses.
Organic evolution occurs so slowly that it has only been possible to observe and experiment with ``micro-evolution'', changes in the size an shapes of parts of organisms. Except through fossil studies, it has not been possible to study ``macro-evolution'', the gain or loss of parts of organisms, and the origins of species and higher taxonomic groups.
Yet evolution in digital systems occurs so quickly, that there are substantial changes in the structure of organisms, and the emergence of entire phylogenies, overnight. Even so, the digital systems are relatively much less complex than organic life, and it can be expected that if digital organisms become more complex, their rate of evolution will slow proportionately.