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Additional figures and tables supporting the results section of 'Quaternary megafauna extinctions altered body size distribution in tortoises'.;Table S1: Body size data set of fossil testudinids. Contains information on locality, taxonomy (Genus and Species name), straight carapace length [mm], age and geographic distribution. Additionally, it is stated whether carapace length was directly measured (m: exact measurements provided in reference, mf: measured from scaled figure, mo: estimated by original authors) or estimated (e: estimated from fragmentary carapace/plastron, ev: estimated from verbal description, ep: estimated from plastron length, ef: estimated from femur length, eh: estimated from humerus length, ec: estimated from claw phalanges). Further, it is stated on which continent the fossil record was recovered and whether it was continental (n: no) or insular (y: yes). Lastly, the reference from which the data were obtained is listed.;Table S2: Body size data set of extant testudinids. Contains information on Genus and Species names, collection numbers (Coll.-Nr.) and shell measurements (SCL: straight carapace length, CCL: curved carapace length, SCW: straight carapace width, CCW: curved carapace%"width, CH: carapace height, PL: plastron length (greatest), PW: plastron width (greatest). Further, geographic distribution is stated and whether species is continental (n: no) or insular (y: yes). Lastly, it is indicated whether the data was directly measured from collection material (Museum für Naturkunde) or the reference from which the measurement data were obtained.;Table S3: Table S3: Additional body size data of extant testudinids from sources reporting the data as summary statistics, these were only used in the paleoTS analysis that was conducted by summarising mean SCL per genus. Contains information on Genus and Species names, age, sample size, mean SCL and standard variation, and reference. Further, geographic distribution is indicated and whether the species is continental (n: no) or insular (y: yes).

Additional figures and tables supporting the results section of 'Quaternary megafauna extinctions altered body size distribution in tortoises'.

Covariation among behavioral and physiological traits is thought to enhance reproductive success and Darwinian fitness. Species that exhibit alternative mating strategies provide excellent opportunities to assess the relative contributions of physiological and behavioral traits to fitness. Male side-blotched lizards (Uta stansburiana) exhibit three heritable throat color morphs that are associated with alternative mating behaviors. The three morphs differ in resource holding potential, mate attraction, mate defense, and physiological performance. We examined interrelationships of body mass, stamina, field metabolic rate, growth rate, and survival to the second capture (a fitness proxy). Relationships among variables were complex, and mass, stamina, and throat color interacted to predict male survival. Our analyses suggest that male side-blotched lizards exhibit trade-offs among physiological traits related to reproductive success and survival and that differential survival for different combinations of traits has caused correlational selection, leading to adaptive integration of phenotypic traits associated with alternative mating strategies.

Ambient temperature is a primary factor affecting the physiology and activity of reptiles. Thermoregulation involves a series of mechanisms to maintain an organism's body temperature within a narrow range. The study of thermal ecology of lizards is relevant for understanding their distribution, life history, ecology and thermal requirements. Moreover, determining how species are able to attain physiologically active body temperatures in challenging environments is necessary for assessing the risk of extinction due to climate change, especially for threatened endemic species. We evaluated and compared the thermal ecology of two populations of the viviparous lizard Barisia imbricata, at contrasting elevations (2,200 and 3,700 m). We obtained variation in thermal data from winter through autumn for multiple years. We determined thermal efficiency indices based on field active body temperatures, preferred temperatures (in a thermal gradient), and operative environmental temperatures (according to null models). We also recorded substrate and air temperatures at the time of capture. Mean body temperature of both populations showed a positive correlation with environmental temperatures. We found significant seasonal differences in body temperature in both populations, and between body temperatures of the two populations. Our results suggest that B. imbricata is an eurythermic species and can thermoregulate actively at any given time. However, when environmental temperatures are within the range of preferred temperatures, the species does not engage in thermoregulatory behavior. This information expands knowledge on the range of possible thermal responses to environmental variation within a species.

Figure S1. Habitat structure differed between the sites on (A) Exuma and (B) Eleuthera.

Knowledge of the thermal ecology of a species can improve model predictions for temperature‐induced population collapse, which in light of climate change is increasingly important for species with limited distributions. Here, we use a multi‐faceted approach to quantify and integrate the thermal ecology, properties of the thermal habitat, and past and present distribution of the diurnal, xeric‐adapted, and active‐foraging Namibian lizard Pedioplanis husabensis (Sauria: Lacertidae) to model its local extinction risk under future climate change scenarios. We asked whether climatic conditions in various regions of its range are already so extreme that local extirpations of P. husabensis have already occurred, or whether this micro‐endemic species is adapted to these extreme conditions and uses behavior to mitigate the environmental challenges. To address this, we collected thermoregulation and climate data at a micro‐scale level and combined it with micro‐ and macroclimate data across the species’ range to model extinction risk. We found that P. husabensis inhabits a thermally harsh environment, but also has high thermal preference. In cooler parts of its range, individuals are capable of leaving thermally favorable conditions—based on the species’ thermal preference—unused during the day, probably to maintain low metabolic rates. Furthermore, during the summer, we observed that individuals regulate at body temperatures below the species’ high thermal preference to avoid body temperatures approaching the critical thermal maximum. We find that populations of this species are currently persisting even at the hottest localities within the species’ geographic distribution. We found no evidence of range shifts since the 1960s despite a documented increase in air temperatures. Nevertheless, P. husabensis only has a small safety margin between the upper limit of its thermal preference and the critical thermal maximum and might undergo range reductions in the near future under even the most moderate climate change scenarios.

Climate change is resulting in a radical transformation of the thermal quality of habitats across the globe. Whereas species have altered their distributions to cope with changing environments, the evidence for adaptation in response to rising temperatures is limited. However, to determine the potential of adaptation in response to thermal variation, we need estimates of the magnitude and direction of natural selection on traits that are assumed to increase persistence in warmer environments. Most inferences regarding physiological adaptation are based on interspecific analyses, and those of selection on thermal traits are scarce. Here, we estimate natural selection on major thermal traits used to assess the vulnerability of ectothermic organisms to altered thermal niches. We detected significant directional selection favouring lizards with higher thermal preferences and faster sprint performance at their optimal temperature. Our analyses also revealed correlational selection between thermal preference and critical thermal maxima, where individuals that preferred warmer body temperatures with cooler critical thermal maxima were favoured by selection. Recent published estimates of heritability for thermal traits suggest that, in concert with the strong selective pressures we demonstrate here, evolutionary adaptation may promote long-term persistence of ectotherms in altered thermal environments.