Updated project metadata. Is is a fundamental evolutionary question which coordinated molecular changes underly adaptation generally and thermal adaptation specifically. Here we profiled the proteome of the Planarian glacial relict species Crenobia alpina. We sampled individuals from an alpine spring, acclimated groups of individuals at 8, 11, 14 and 17 °C for one week and determined their proteome. These results give insight into the molecular mechanisms underlying thermal adaptation and acclimation to cold and warm temperatures.