 The genotype-phenotype distinction can also signify that the surface—phenotype—is mere appearance; what is underneath or inside that surface—the genotype—is what counts. A small irony, given that the phenotype originated in relation to inferring genotypes (in the sense of a class that shared something unobservable), is that, to the extent that molecular biology has made DNA sequences observable, especially at sites in which the sequences vary from one group to another, each genotype (in the sense of a pair of genes or DNA sequence) becomes another phenotype (Nachtomy et al. 2009). During the development of an organism, each of these genotypes-as-phenotypes at time 0 interacts with the rest of the phenotype and environmental factors to produce the phenotype at time 1, 2, and so on. It may well be the case that germ cells arise at some point in the life course that are buffered from most of these interactions. However, with respect to conceptualizing development from time 0 till death, nothing logically makes the genotype not also a phenotype.