Enhanced locomotor performance on familiar surfaces is uncoupled from morphological plasticity in Anolis lizards

Abstract

The radiation of Anolis lizards in the Caribbean is associated with a diversification of the functional match between morphology, habitat use, and locomotor performance.It has been hypothesized that the microhabitat a lizard is reared in can achieve a similar fit of form and function within a species. This predicts that plasticity in the locomotor apparatus is accompanied by changes in perching behavior or improved locomotor performance. To test this, we raised juveniles of two species (Anolis sagrei and Anolis carolinensis) on either broad or narrow surfaces and examined perching behavior and locomotor performance as well as the shape of the pectoral and pelvic girdles, limb length, and thickness of the long bones. Perching behavior was not affected by the habitat surface experienced during ontogeny. However, individuals raised on broad surfaces showed better locomotor performance on broad surfaces, and the magnitude of the effect was as large as the difference between the two species. Both species showed modifications of pectoral and pelvic shape, but only A.carolinensis developed longer limbs on broad surfaces. However, these morphological adjustments induced by physical activity did not explain why lizards raised on broad surfaces performed better. Thus, it appears that early-life experiences can affect both the morphology of the locomotor apparatus and locomotor performance in Anolis lizards, without the two being functionally connected. K E Y W O R D Sbehavior, limb morphology, lizards, locomotion, phenotypic integration, plasticity

Plasticity and evolutionary convergence in the locomotor skeleton of Greater Antillean Anolis lizards

“…To test this hypothesis, we raised 45 male lizards of a trunk-crown ( Anolis carolinensis , adapted to climbing) and 71 male lizards of a trunk-ground ( A. sagrei , adapted to running) species on broad versus narrow surfaces until they reached adulthood ( Figure 4—figure supplement 2 ). The differences in the structural habitats promoted different styles of locomotion and perching behaviour ( Feiner et al, 2020 ). Both species belong to the Cuban clade and, therefore, the appropriate evolutionary divergence to compare against is the contrast between the respective ecomorphs in this clade on Cuba (trunk-ground [N Individuals = 20, N Species = 9] versus trunk-crown [N Individuals = 20, N Species = 9]).…”

“…To assess how well morphology predicts functional aspects related to fitness, we performed two trials that capture perching behaviour and locomotor performance in the lizards that were raised in the two microhabitats (see Material and methods). First, we assessed perching behaviour, and second, we scored running performance on broad and narrow surfaces (see Feiner et al, 2020 ) for more details). We have previously shown that locomotor performance was enhanced in the familiar microhabitat ( Feiner et al, 2020 ).…”

“…First, we assessed perching behaviour, and second, we scored running performance on broad and narrow surfaces (see Feiner et al, 2020 ) for more details). We have previously shown that locomotor performance was enhanced in the familiar microhabitat ( Feiner et al, 2020 ). Here, we demonstrate that this effect was largely uncoupled from morphological plasticity: in both species, the first two principal components of the 14 resp.…”

“…Both are derived from the Cuban clade, which allows us to compare trajectories between plastic responses and morphological divergence between the ecomorphs in this clade. The following information is a brief summary of the detailed description in Feiner et al, 2020 .…”

“…During this trial period, we recorded positions (i.e., the distance away from the tip of the dowel) where the lizard was resting for more than 5 s and calculated the average position as the mean of all positions. A subset of lizards was also tested at 4 months of age to determine individual consistency ( Feiner et al, 2020 ).…”