 Dawkins introduced the general notions of replicator and vehicle so that selection need not be limited exclusively to gene-based biological evolution. However, as the preceding discussion indicates, his later revisions to his general theoretical outlook were influenced strongly by the traditional perspective of genes and organisms. Genes contain the information necessary to produce organisms and their adaptations. Genes “ride around” in and “guide” organisms. As Dawkins describes them, vehicles are relatively discrete entities that “house” replicators and that can be regarded as machines programmed to preserve and propagate the replicators that ride inside them. Although these terms may be appropriate for the relations between genes and organisms, they interfere with a more general analysis of replication and selection. What really matters in selection is that entities at various levels of organization interact with their environments in such a way that the relevant replicators increase in relative frequency. The actual causal chain that connects replicators and vehicles need not be limited to development.