Data Explanation File Data File: Ril_data Sheet: Phenotype Column explanations: ID: unique id number allocated to each fly. Line: is an identification for each line. EUNGC is the founder from Eungella and Fors4 is the founder from Forster. Type: is the identification to distinguish between the RIL and the founding line (parent) Sex: f for females, m for males. Block: as described in the paper, measurements were done in twelve experimental runs or blocks. Vial: vial number represents what vial the fly developed in. Codes are nested within lines. T25: fly's activity measured at 25 degrees celsius in counts per 20min. T30: fly's activity measured at 30 degrees celsius in counts per 20min. T33: fly's activity measured at 33 degrees celsius in counts per 20min. T35: fly's activity measured at 35 degrees celsius in counts per 20min. T36: fly's activity measured at 36 degrees celsius in counts per 20min. T38: fly's activity measured at 38 degrees celsius in counts per 20min. Sheet: Markers Column 1: an identification for each line. Eu is the Eungella founder, Fo is the founder from Forster and the remaining are the RILs. Column 2-50: each column represents marker 1 to 49. Markers 1- 18 & 21-27 are microsatelites, markers 28 - 34 are dCAPS and markers 19-20 & 35-49 are EST derived SNP. Coding: 1 = Eungella, 2 = Forster, 0 = missing, 3 = heterozygote.