Comparative sequence analyses on a collection of carefully chosen mammalian genomes could facilitate identification of functional elements within the human genome and allow quantification of evolutionary constraint at the single nucleotide level. High-resolution quantification would be informative for determining the distribution of important positions within functional elements and for evaluating the relative importance of nucleotide sites that carry single nucleotide polymorphisms (SNPs). The level of resolution in comparative sequence analyses is a direct function of sequence diversity, so the information content of a candidate mammalian genome can be defined as the sequence divergence it would add relative to alreadysequenced genomes. Our study involves sequences from 29 mammals and we compute total neutral divergence present in set of mammals. Our results of how different mammals add to neutral divergence to the already fully sequenced mammals would increases the effectiveness of comparative genomics with mammalian scope.