Extended Data Fig. 7: The evolutionary history of odorant receptors in terrestrial sauropsids.
From: The tuatara genome reveals ancient features of amniote evolution
The relationship among odorant receptors was inferred using the neighbour-joining method. The unrooted tree contains 3,213 amino acid sequences. Branches are coloured according to the following categories: green, tuatara; blue, birds (G. gallus and Taeniopygia guttata); red, snakes (Notechis scutatus, Ophiophagus hannah, Protobothrops mucrosquamatus, Pseudonaja textilis, P. bivittatus and Thamnophis sirtalis); orange, lizards (A. carolinensis and Pogona vitticeps); and purple, gecko (Gekko japonicas). Bootstrap support values above 75% (1,000 replicates) are indicated for major branch splits relating to the different odorant receptor groups and branches leading to the species-specific odorant receptor expansions in birds (group γ–c) and tuatara (*).
