Feeding Behaviour of the Columbretes Lizard \u3ci\u3ePodarcis atrata\u3c/i\u3e, in Relation to \u3ci\u3eIsopoda (Crustaceae)\u3c/i\u3e Species: \u3ci\u3eLigia italica\u3c/i\u3e and \u3ci\u3eArmadillo officinalis\u3c/i\u3e

The lizard Podarcis atrata, endemic to the Columbretes archipelago (Mediterranean, Spain) occupies very small islands characterized by extreme aridity and a reduced availability of potential insect prey. The results of an experimental study have shown that adult lizards offered individuals of Ligia italica and Armadillo officinalis (marine and terrestrial isopods, respectively) consumed at high frequencies; with males consuming them at significantly higher frequencies than females. The results are discussed in light of the importance of the inclusion of marine prey into the diet in arid insular ecosystems

Do the relationships between hindlimb anatomy and sprint speed variation differ between sexes in Anolis lizards?

The ability of an animal to run fast has important consequences on its survival capacity and overall fitness. Previous studies have documented how variation in the morphology of the limbs is related to variation in locomotor performance. Although these studies have suggested direct relations between sprint speed and hindlimb morphology, few quantitative data exist. Consequently, it remains unclear whether selection acts in limb segment lengths, overall muscle mass or muscle architecture (e.g. muscle fiber length and cross-sectional area). Here, we investigate whether muscle architecture (mass, fiber length and physiological cross-sectional area), hindlimb segment dimensions, or both, explain variation in sprint speed across 14 species of Anolis lizards. Moreover, we test whether similar relationships exist between morphology and performance for both sexes, which may not be the case given the known differences in locomotor behavior and habitat use. Our results show that the main driver of sprint speed is the variation in femur length for both males and females. Our results further show sexual dimorphism in the traits studied and, moreover, show differences in the traits that predict maximal sprint speed in males and females. For example, snout vent length and overall muscle mass are also good predictors of sprint speed in males, whereas no relationships between muscle mass and sprint speed was observed in females. Only a few significant relationships were found between muscle architecture (fiber length, cross-sectional area) and sprint speed in male anoles, suggesting that overall muscles size, rather than muscle architecture, appears to be under selection

Developmental plasticity affects sexual size dimorphism in an anole lizard

This is the peer reviewed version of the following article: Bonneaud, C., Marnocha, E., Herrel, A., Vanhooydonck, B., Irschick, D. J., Smith, T. B. (2015), Developmental plasticity affects sexual size dimorphism in an anole lizard. Functional Ecology, which has been published in final form at 10.1111/1365-2435.12468. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving: http://olabout.wiley.com/WileyCDA/Section/id-820227.html#termsSummary While developmental plasticity has been shown to contribute to sexual size dimorphism (SSD) in laboratory studies, its role in shaping SSD variation in wild vertebrate populations is unclear. Here we use a field study and a laboratory experiment to show that resource availability influences the degree of SSD among insular populations of Anolis sagrei lizards in the Bahamas. Total amounts of food biomass explained variation in male, but not female, body size on six Bahamian islands, giving rise to significant differences in SSD. Laboratory experiments on a captive colony of A. sagrei confirmed that variation in SSD was mediated by the effects of prey biomass on developmental plasticity in males, but not females. Indeed, males grew faster and attained larger sizes as adults under high-food treatments than under restricted diets, whereas adult females retained similar body sizes under both conditions. Our results indicate that the amount of food available can influence intersexual variation in body size within a vertebrate species. Sex-specific developmental plasticity may be favoured if it allows individuals to take advantage of varying levels of food opportunities offered by different habitats, by reducing competition between the sexes. As such, plasticity in response to food availability may have played a role in the invasion success of A. sagrei. This study adds to our growing understanding of the effect of resource availability in shaping SSD in reptiles and lends further support to the condition-dependent hypothesis, according to which the larger sex should display greater plasticity in growth in response to environmental conditions.Marie Curie Reintegration GrantUnited States Environmental Protection AgencyUCLA Department of Ecology and Evolutionary BiologyFund for Scientific Research (FWO-Vl), BelgiumNational Science Foundatio

Proximate causes of intraspecific variation in locomotor performance in the lizard Gallotia galloti

ABSTRACT To understand the evolution of biological traits, information on the degree and origins of intraspecific variation is essential. Because adaptation can take place only if the trait shows heritable variation, it is important to know whether (at least) part of the trait variation is genetically based. We describe intraand interindividual variation in three performance measures (sprint speed, climbing, and clambering speed) in juvenile Gallotia galloti lizards from three populations and examine how genetic, environmental (incubation temperature), and ontogenetic (age, size) effects interact to cause performance variation. Moreover, we test whether the three performance traits are intercorrelated phenotypically and genetically. Sprint speed is highest in juveniles incubated at the lowest temperature (26ЊC) irrespective of population. Climbing speed differs among populations, and the differences persist at least until the lizards are 30 wk old. This suggests that the three populations experience different selective pressures. Moreover, mass, snoutvent length, and hindlimb length seem to affect climbing performance differently in the three populations. The variation in sprinting and climbing ability appears to be genetically based. Moreover, the two performance traits are intercorrelated and thus will not evolve independently from each other. Clambering speed (i.e., capacity to climb up an inclined mesh) varies among individuals, but the origin of this variation remains obscure

Push and bite: trade-offs between burrowing and biting in a burrowing skink (Acontias percivali)

International audienc

Functional consequences of morphological differentiation between populations of the Cape Dwarf Chameleon (Bradypodion pumilum)

International audienc

Evolutionary biology - Performance constraints in decathletes

Physical performance by vertebrates is thought to be constrained by trade-offs between antagonistic pairs of ecologically relevant traits and between conflicting specialist and generalist phenotypes1, 2, but there is surprisingly little evidence to support this reasoning3, 4, 5. Here we analyse the performance of world-class athletes in standardized decathlon events and find that it is subject to both types of trade-off, after correction has been made for differences between athletes in general ability across all 10 events. These trade-offs may have imposed important constraints on the evolution of physical performance in humans and other vertebrates

Intraspecific variation in the information content of an ornament : why relative dewlap size signals bite force in some, but not all island populations of Anolis sagrei

In many animals, male secondary sexual traits advertise reliable information on fighting capacity in a male-male context. The iconic sexual signaling device of anole lizards, the dewlap, has been extensively studied in this respect. For several territorial anole species (experiencing strong intrasexual selection), there is evidence for a positive association between dewlap size and bite capacity, which is an important determinant of combat outcome in lizards. Intriguingly, earlier studies did not find this expected correlation (relative dewlap size-relative bite force) in the highly territorial brown anole lizard, Anolis sagrei. We hypothesize that the dewlap size-bite force relationship can differ among populations of the same species due to interpopulation variation in the degree of male-male competition. In line with this thought, we expect dewlap size to serve as a reliable predictor of bite performance only in those populations where the level of intrasexual selection is high. To tackle this hypothesis, we examined the relationship between male dewlap size and bite force on the intraspecific level in A. sagrei, using an extensive dataset encompassing information from 17 island populations distributed throughout the Caribbean. First, we assessed and compared the relationship between both variables in the 17 populations under study. Second, we linked the relative dewlap size-bite force relationship within each population to variation in the degree of intrasexual selection among populations, using sexual size dimorphism and dewlap display intensity as surrogate measures. Our results showed that absolute dewlap size is an excellent predictor of maximum bite force in nearly all A. sagrei populations. However, relative dewlap size is only an honest signal of bite performance in 4 out of the 17 populations. Surprisingly, the level of signal honesty did not correlate with the strength of intrasexual selection. We offer a number of conceptual and methodological explanations for this unexpected finding

Got It Clipped? The Effect of Tail Clipping on Tail Gripping Performance in Chameleons

International audienc

Diving in head first: trade-offs between phenotypic traits and sand-diving predator escape strategy in Meroles desert lizards

International audienc