Figure 2.

Proposed model for fur evolution. A. Phylogenetic tree of 16S nucleotide sequences generated by NJ analysis. The numbers beside nodes are the percentages of bootstrap values calculated for 10000 replicates: only those above 50% are represented. Evolutionary events are indicated by a short coloured line: blue for duplications and red for losses. In front of the species name, the number of homologues belonging to each one of the groups A, B, C, D and E is indicated. B. Schematic model of fur evolution. The losses and duplications referred on 2A are here located in terms of homologues gain and lost.