Supplement 1. Data and formulas used in the analyses on body size and richness.

File List Verberk body size.xls Verberk body size.csv Verberk richness.xls Verberk richness.csv Description [Please be aware that ESA cannot guarantee the forward migration (availability) of the Excel (.xls) files] Verberk body size.xls gives all the data and formulae used to analyze the relationship between amphipod body size and clines in environmental conditions purportedly linked with oxygen (altitude, temperature, salinity). Verberk body size.csv is a comma-delimited version of the body size worksheet, giving all the data and the calculated values for the oxygen supply index, but without the formulae. Verberk richness.xls gives all the data and formulae used to analyze the relationship between species richness and clines in environmental conditions purportedly linked with oxygen (altitude, organic pollution, temperature). Verberk richness.csv is a comma-delimited version of the richness worksheet, giving all the data and the calculated values for the oxygen supply index, but without the formulae. Check sum values for: Verberk body size.xls and .csv: column 1 (Site descriptors): checksum is 136, no missing values Verberk richness.xls: column 1 (Site descriptors): checksum is 655, 3 missing values Verberk richness.csv: column 2 (Site descriptors): checksum is 655, 3 missing values