Table 1. Detail of populations sampled for sequencing and SNP discovery.

C. gigas			O. edulis
Population	Location (Lat, Long)	N	Population	Location (Lat, Long)	N
Guernsey, England	49.497, −2.502	47	Croatia	42.855, 17.688	14
Maldon, England	51.724, 0.710	15	Lough Foyle, Ireland	55.130, −7.087	15
Sea Salter, England	51.378, 1.212	13	Lake Grevelingen, The Netherlands	51.709, 4.017	15
Ifremer, France	n/a	16	Larne, Northern Ireland	54.817, −5.751	14
Hatchery 1 (Marinove), France	46.987, −2.238	29	Mersea, England	51.776, 0.9646	15
Hatchery 2 (SATMAR), France	46.948, −2.052	26	Baie de Quiberon, France	47.548, −2.996	15
Hatchery 3 (France Naissain), France	47.514, −2.666	29	Rossmore (Cork), Ireland	51.883, −8. 247	15
Hatchery 4 (Novostrea), France	46.954, −2.044	28	Sveio, Norway	59.519, 5.227	15
			Swansea Bay, England	51.604, −3.981	15
			Tralee, Ireland	52.316, −10. 028	13
			Damariscotta, Maine	44.028, −69.534	14

Lat, latitude; Long, longitude.