Fig. 1

The speciation continuum of the Heliconius erato clade. Three stages along the speciation continuum are shown, from a hybridizing pair with no reproductive isolation and minimal color pattern divergence, to a hybridizing pair with strong reproductive isolation and color pattern divergence. For each stage we show details, including color pattern differences [8, 25, 29, 30], the hybrid zone estimates [10, 12, 13, 16–18], the type of reproductive isolation [8, 10, 14–18, 33], and habitat differences [18, 51]. Hybrid zones shown are Panama (H. e. hydara, H. e. petiverana), Ecuador (H. e. notabilis, H. e. lativitta), Peru (H. e. favorinus, H. e. emma), French Guiana (H. e. hydara, H. e. erato), Ecuador (H. e. cyrbia, H. himera)