Anaerobic metabolism and activity of European lacertid lizards.

1. Lactate production and physical performance during intense activity were measured in Lacerta vivipara, Podarcis muralis and Podarcis hispanica, temperate lizards from progressively lower latitudes. 2. Rates of lactate production during the initial 30 sec of bursts of activity (means = 1.75 mg g-1) and their Q10S (means = 1.36) are similar to previously obtained values for lizards. 3. Maximal anaerobic scope at activity body temperatures is lowest in Lacerta vivipara, which correlates with a tendency to less strenuous behaviour than that of the Podarcis species and may reflect the need for energy economy. 4. Q10S of maximal performance are lower in Lacerta vivipara and Podarcis muralis than Podarcis hispanica, a difference having no demonstrated metabolic basis but which is thermally adaptive for these cooler climate species.