Figure 1From: Evolutionary dynamics of olfactory receptor genes in chordates: interaction between environments and genomic contentsNumbers of OR genes in 23 chordate species[12–14]. F, T and P indicate the numbers of functional genes, truncated genes and pseudogenes, respectively. A truncated gene is part of an intact sequence that is located at a contig end. The fraction of pseudogenes (P per cent) in each species was estimated by assuming that all truncated genes are functional[12]. Phylogenetic relationships among the 23 species are also shown.Back to article page