Ecomorphological correlates of habitat partitioning in Corsican lacertid lizards

1. Morphological features (i.e. snout-vent length, SVL, mass and limb parameters), locomotor performance (sprint speed, climbing speed, manoeuvrability and endurance) and microhabitat use were measured in three lacertid lizard species. Additionally, microhabitat preference was tested in the laboratory with species kept apart and in combination with each other to assess mutual interference. 2, It was predicted that each species possesses morphological adaptations that allow it to excel in those performance measures relevant in its particular microhabitat. 3, The three species differed in microhabitat use. Lacerta bedriagae was mostly seen on boulders, while Podarcis sicula occurred among vegetation. Podarcis tiliguerta seemed more general in its microhabitat use. The results from the microhabitat preference in the laboratory corresponded well to these field observations. 4. Besides differing in SVL, the three species differed in limb length and diameter, and body mass tall relative to SVL). L. bedriagae has long forelimbs, short hindlimbs and a high body mass, while P. sicula has short forelimbs, long hindlimbs and a low body mass. P. tiliguerta is morphologically intermediate. 5. The differences found in morphology translated partially into performance differences. Only climbing speed and endurance differed among species. L. bedriagae excelled in both cases. Considering its microhabitat use, this seemed adaptive. 6, Unexpectedly, the interference experiments suggested that L. bedriagae is the least competitive of the three species.