Lizards and Climate Change
Temperature is an important factor affecting biological processes in all forms of life. For example, geographical distribution, the speed of enzyme actions, muscle contractions, defense behavior, foraging performance, and reproduction are all impacted by temperature. Therefore it is not surprising that global warming is equal to habitat loss as the most important cause of the ongoing biodiversity crisis.</p>\n<!– /wp:paragraph –><!– wp:paragraph –>\n<p>Diaz et al. (2022) used a 30-year database of body temperatures of the free-ranging lizard known as the Algerian Sand Racer, <em>Psammodromus algirus</em>, that inhabits the temperate open forest. They focused on the summers of 1997 and 2017 to compare body temperatures, environmental operative temperatures, their proximity to the selected thermal range, and the selection of sunlit and shaded patches throughout the day. From these data, they estimated the precision, accuracy, and effectiveness of thermoregulation.</p>\n<!– /wp:paragraph –><!– wp:paragraph –>\n<p>The Algerian Sand Racer is a medium-sized (adult body length 60–85 mm; mass 6–15 g) heliothermic lacertid that inhabits shrub and woodland habitats of the western Mediterranean. Lizards were sampled at ‘El Pardo’ (Madrid, central Spain), in a holm oak perennial forest. In July–August, the mean ambient temperature is 25.2°C (average of the 40 years between 1978 and 2017), and the mean daily maximum temperature is 33.0°C.The highest 5% of all body temperatures in the database, 95%, were recorded in 2017. In 2017, especially after 12:00 h, 87% of the lizards were in full shade versus less than 1% in full sun. Despite this, body temperatures were lower—and closer to those in 1997 (when most shaded patches offered favorable thermal opportunities. Consequently, estimates of the accuracy and effectiveness of thermoregulation decreased over the 20 years examined. The authors concluded that the lizards could no longer prevent the rise of their body temperature above environmental temperature on hot summer days. Thus, the effects of global warming are already hindering the ability of lizards to buffer environmental change by behavioral means, even in temperate forests with a fine-grained mosaic of sun and shade patches
