An overabundance of Grs expressed in female legs are the result of Heliconius-specific duplication.

*Consists of single-copy genes in H. melpomene; in the monarch or Bombyx genomes, homologues are either single-copy or duplicate genes with bootstrap support ≥80%.†Fisher's exact test, two-tailed, d.f. = 1.‡Excludes Gr39 because of poor coverage in the reference genome read-mapping.§Excludes Or20 and Or24 because of coverage in the reference genome.