| patterns of infection of the lizard malaria parasite, plasmodium floridense, in invasive brown anoles (anolis sagrei) in southwestern florida. | plasmodium floridense is a saurian malaria parasite common in the anolis lizards of the northern caribbean islands and the se usa. in the latter area, it is found in two native lizards (sceloporus undulatus and anolis carolinensis) and in the introduced anolis sagrei, which is native to cuba. we measured parasite prevalence and parasitemia in the introduced anole at a single site in north port, florida over 5 years. prevalence, based on microscopic examination of blood smears, was high year-roun ... | 2009 | 19085004 |
| parallel shifts in ecology and natural selection in an island lizard. | natural selection is a potent evolutionary force that shapes phenotypic variation to match ecological conditions. however, we know little about the year-to-year consistency of selection, or how inter-annual variation in ecology shapes adaptive landscapes and ultimately adaptive radiations. here we combine remote sensing data, field experiments, and a four-year study of natural selection to show that changes in vegetation structure associated with a severe drought altered both habitat use and nat ... | 2009 | 19126226 |
| effects of the brown anole invasion and betelnut palm planting on arthropod diversity in southern taiwan. | the brown anole ( anolis sagrei ) occurs naturally in various localities in central america, and an exotic invasive population was first reported in sheishan district, chiayi county, taiwan, in 2000. previous studies showed that following the invasion of a. sagrei , the diversity and abundance of local terrestrial arthropods, such as orb spiders and arboreal insects, were severely affected. in this study, we assessed the impact of a. sagrei on arthropod diversity in taiwan by comparing spider an ... | 2008 | 19267623 |
| alteration of island food-web dynamics following major disturbance by hurricanes. | major abiotic disturbance can be an important factor influencing food-web dynamics, particularly in areas impacted by the recent increase in hurricane activity. we present a unique set of data on key food-web processes occurring on 10 small islands for three relatively calm years and then four subsequent years during which two hurricanes passed directly over the study site. herbivory, as measured by leaf damage, was 3.2 times higher in the year after the first hurricane (2000) than in the previo ... | 2007 | 17489451 |
| reptilian transferrins: evolution of disulphide bridges and conservation of iron-binding center. | transferrins, found in invertebrates and vertebrates, form a physiologically important family of proteins playing a major role in iron acquisition and transport, defense against microbial pathogens, growth and differentiation. these proteins are bilobal in structure and each lobe is composed of two domains divided by a cleft harboring an iron atom. vertebrate transferrins comprise of serotransferrins, lactoferrins and ovotransferrins. in mammals serotransferrins transport iron in physiological f ... | 2007 | 17466466 |
| nonsynchronous recovery of community characteristics in island spiders after a catastrophic hurricane. | we monitored spiders on 41 bahamian islands for 4 years before and then 4 years after the catastrophic hurricane floyd passed directly over the site, inundating the study islands with its storm surge. the respective recoveries of major community properties after this annihilation were far from synchronous. before the hurricane, the species-area relation was generally strong and the slope showed no temporal trend. after the hurricane, the slope increased from near zero (7 months later) to a value ... | 2006 | 16452167 |
| island biogeography of populations: an introduced species transforms survival patterns. | population phenomena, which provide much of the underlying basis for the theoretical structure of island biogeography, have received little direct study. we determined a key population trait-survival-in the bahamian lizard anolis sagrei on islands with an experimentally introduced predatory lizard and on neighboring unmanipulated islands. on unmanipulated islands, survival declined with several variables, most notably vegetation height: the island with the shortest vegetation had nearly the high ... | 2005 | 16357259 |
| female sperm storage in reptiles. | internal fertilization and oviparity most likely are symplesiomorphies for modern reptiles, and viviparity has evolved independently numerous times in sauria and serpentes. oviducal sperm storage is known in females of all taxa except amphisbaenia. however, in rhynchocephalia and crocodilia, sperm storage is poorly studied, and specialized sperm storage tubules (ssts) are unknown. we use the molecular phylogenetic hypothesis [(chelonia+archosauria) (squamata)] to trace evolution of sperm storage ... | 2002 | 11754034 |
| natural restoration of the species-area relation for a lizard after a hurricane. | we document the decimation and recovery of the commonest lizard species, anolis sagrei, on 66 islands in the bahamas that were directly hit by hurricane floyd in september 1999. before the hurricane, an island's area was a better predictor of the occurrence of a. sagrei than was its altitude. immediately after, altitude was a better predictor: apparently all lizards on islands lower than about 3 meters maximum elevation perished in the storm surge. after about 1 year, area again became the bette ... | 2001 | 11711674 |
| transport of helminths to hawaii via the brown anole, anolis sagrei (polychrotidae). | sixty-two brown anoles, anolis sagrei, from oahu, hawaii were examined for helminths. anolis sagrei was introduced to hawaii, presumably from the caribbean. two species of trematodes, mesocoelium monas and platynosomum fastosum, 3 species of nematodes, atractis scelopori, physaloptera squamatae, and physocephalus sp., 1 acanthocephalan, acanthocephalus bufonis, and 1 pentastome, raillietiellafrenatus, were found. atractis scelopori and p. squamatae, previously unknown in hawaii, are widely distr ... | 2000 | 10958451 |
| molecular differentiation of two new world saurian plasmodium species in different host species using the polymerase chain reaction. | several isolates of plasmodium floridense obtained from naturally infected anolis carolinensis and anolis sagrei, and 2 isolates of plasmodium chiricahuae obtained from sceloporus jarrovi were characterized at the ribosomal dna (rdna) locus using the polymerase chain reaction and agarose gel electrophoresis. enzymatic amplification of the rdna locus from both plasmodium species resulted in the generation of a 590-base pair (bp) dna fragment. the results obtained with all isolates of p. floridens ... | 1996 | 8604124 |
| the fate of hepatozoon species naturally infecting florida black racers and watersnakes in potential mosquito and soft tick vectors, and histological evidence of pathogenicity in unnatural host species. | haemogregarine parasites, derived from the florida snakes coluber constrictor and nerodia fasciata and ingested by aedes aegypti, completed sporogony within the hemocoeles of nearly all fed mosquitoes in 14-18 days, and produced oocysts typical of hepatozoon. however, mortalities and morbidity were high in the culex which had fed on the coluber. oocysts were not found in any ornithodoros turicata (argasidae) which fed upon either snake host, but many sections of fed ticks had gametocyte-like cel ... | 1991 | 1683862 |
| the metabolic cost of mounting an immune response in male brown anoles (anolis sagrei). | the tradeoff between reproduction and survival is central to life-history theory and is thought to reflect underlying energetic tradeoffs between reproduction and self-maintenance. immune responses to parasites and pathogens are important components of self-maintenance in many species, but whether these defenses impose significant energetic costs has only been tested in a handful of organisms. we tested for a metabolic cost of mounting an immune response in the male brown anole (anolis sagrei), ... | 2015 | 26350753 |
| intersexual chemo-sensation in a "visually-oriented" lizard, anolis sagrei. | while the conspicuous visual displays of anoles have been studied in great depth, the possibility that these lizards may also interact through chemical signalling has received hardly any consideration. in this study, we observed the behaviour of male brown anoles (anolis sagrei) when introduced into an environment previously inhabited by female conspecifics, and compared it to when they were introduced into an untreated environment. the males in our tests exhibited significantly more elaborate d ... | 2016 | 27069809 |
| urbanization and biological invasion shape animal personalities. | novel selective pressures derived from human activities challenge the persistence of animal populations worldwide. behavior is expected to be a major factor driving animals' responses to global change because it largely determines how animals interact with the environment. however, the role of individual variation in behavior to facilitate the persistence of animals in changing environments remains poorly understood. here, we adopted an animal personality approach to investigate whether differen ... | 2017 | 27310334 |
| spatial variation in climate mediates gene flow across an island archipelago. | high levels of gene flow among partially isolated populations can overwhelm selection and limit local adaptation. this process, known as "gene swamping," can homogenize genetic diversity among populations and reduce the capacity of a species to withstand rapid environmental change. we studied brown anole lizards (anolis sagrei) distributed across seven islands in the bahamas. we used microsatellite markers to estimate gene flow among islands and then examined the correlation between thermal perf ... | 2016 | 27501004 |
| predators suppress herbivore outbreaks and enhance plant recovery following hurricanes. | understanding processes that may stabilize ecological systems confronted with rapidly changing environmental conditions is a key issue in ecology. we studied a system of highly fluctuating populations, the moth achyra rantalis feeding on the plant sesuvium portulacastrum in a group of small subtropical islands of the bahamas. the plant is a prostrate inhabitant of shorelines, and consequently moths are highly vulnerable to being consumed by the ground-foraging lizard anolis sagrei. we measured t ... | 2016 | 27859131 |
| does ecological specialization transcend scale? habitat partitioning among individuals and species of anolis lizards. | ecological specialization is common across all levels of biological organization, raising the question of whether the evolution of specialization at one scale in a taxon is linked to specialization at other scales. anolis lizards have diversified repeatedly along axes of habitat use, but it remains unknown if this diversification into habitat use specialists is underlain by individual specialization. from repeated observations of individuals in a population of anolis sagrei in florida, we show t ... | 2017 | 28012159 |
| validation of body condition indices and quantitative magnetic resonance in estimating body composition in a small lizard. | measurements of body condition are typically used to assess an individual's quality, health, or energetic state. most indices of body condition are based on linear relationships between body length and mass. although these indices are simple to obtain, nonlethal, and useful indications of energetic state, their accuracy at predicting constituents of body condition (e.g., fat and lean mass) are often unknown. the objectives of this research were to (1) validate the accuracy of another simple and ... | 2016 | 28035770 |
| habitat- and season-specific temperatures affect phenotypic development of hatchling lizards. | embryonic environments influence phenotypic development, but relatively few experiments have explored the effects of natural environmental variation. we incubated eggs of the lizard anolis sagrei under conditions that mimicked natural spatial and temporal thermal variation to determine their effects on offspring morphology and performance. incubation temperatures mimicked two microhabitats (open, shade) at two different times of the incubation season (april, july). egg survival, incubation durat ... | 2016 | 28120809 |
| hormonally mediated increases in sex-biased gene expression accompany the breakdown of between-sex genetic correlations in a sexually dimorphic lizard. | the evolution of sexual dimorphism is predicted to occur through reductions in between-sex genetic correlations (rmf) for shared traits, but the physiological and genetic mechanisms that facilitate these reductions remain largely speculative. here, we use a paternal half-sibling breeding design in captive brown anole lizards (anolis sagrei) to show that the development of sexual size dimorphism is mirrored by the ontogenetic breakdown of rmf for body size and growth rate. using transcriptome dat ... | 2017 | 28221827 |
| embryos of non-native anoles are robust to urban thermal environments. | the transformation of natural habitats into urban landscapes dramatically alters thermal environments, which in turn, can impact local biota. ectothermic organisms that are oviparous are particularly sensitive to these altered environments because their embryos cannot behaviorally thermoregulate and the surrounding environment determines the temperature experienced during development. we studied the effects of urban and forested thermal environments on embryo development and hatchling phenotypes ... | 2017 | 28343564 |
| multivariate genetic architecture of the anolis dewlap reveals both shared and sex-specific features of a sexually dimorphic ornament. | darwin viewed the ornamentation of females as an indirect consequence of sexual selection on males and the transmission of male phenotypes to females via the "laws of inheritance." although a number of studies have supported this view by demonstrating substantial between-sex genetic covariance for ornament expression, the majority of this work has focused on avian plumage. moreover, few studies have considered the genetic basis of ornaments from a multivariate perspective, which may be crucial f ... | 2017 | 28370951 |
| visual acuity and signal color pattern in an anolis lizard. | anolis lizards communicate with colorful dewlaps that often include detailed patterns. we measured the visual acuity of anolis sagrei. lizards viewed a checkerboard pattern of red and yellow-green squares that were too small to resolve, and thus appeared uniform in color. we quickly replaced the center portion of the display with a pattern of larger squares. if the new pattern could be resolved, the lizards perceived a change in color and reflexively shifted gaze toward the target. the acuity th ... | 2017 | 28385798 |
| ranavirus infections associated with skin lesions in lizards. | ranaviral disease in amphibians has been studied intensely during the last decade, as associated mass-mortality events are considered to be a global threat to wild animal populations. several studies have also included other susceptible ectothermic vertebrates (fish and reptiles), but only very few cases of ranavirus infections in lizards have been previously detected. in this study, we focused on clinically suspicious lizards and tested these animals for the presence of ranaviruses. virological ... | 2013 | 24073785 |
| invasive predators deplete genetic diversity of island lizards. | invasive species can dramatically impact natural populations, especially those living on islands. though numerous examples illustrate the ecological impact of invasive predators, no study has examined the genetic consequences for native populations subject to invasion. here we capitalize on a natural experiment in which a long-term study of the brown anole lizard (anolis sagrei) was interrupted by rat invasion. an island population that was devastated by rats recovered numerically following rat ... | 2010 | 20706576 |
| experimentally assessing the relative importance of predation and competition as agents of selection. | field experiments that measure natural selection in response to manipulations of the selective regime are extremely rare, even in systems where the ecological basis of adaptation has been studied extensively. the adaptive radiation of caribbean anolis lizards has been studied for decades, leading to precise predictions about the influence of alternative agents of selection in the wild. here we present experimental evidence for the relative importance of two putative agents of selection in shapin ... | 2010 | 20453837 |
| sex-specific selection and intraspecific variation in sexual size dimorphism. | sexual size dimorphism (ssd) is thought to evolve due to sex differences in selection on body size, but it is largely unknown whether intraspecific variation in ssd reflects differences in sex-specific selection among populations. we addressed this question by comparing viability selection between two island populations of the brown anole lizard (anolis sagrei) that differ in the magnitude of male-biased ssd. on both islands, females experienced stabilizing selection favoring intermediate size w ... | 2010 | 19796147 |
| intralocus sexual conflict, adaptive sex allocation, and the heritability of fitness. | intralocus sexual conflict arises when selection favours alternative fitness optima in males and females. unresolved conflict can create negative between-sex genetic correlations for fitness, such that high-fitness parents produce high-fitness progeny of their same sex, but low-fitness progeny of the opposite sex. this cost of sexual conflict could be mitigated if high-fitness parents bias sex allocation to produce more offspring of their same sex. previous studies of the brown anole lizard (ano ... | 2015 | 26310599 |
| herpetofaunal community change in multiple habitats after fifteen years in a southwest florida preserve, usa. | herpetofaunal declines have been documented globally, and southern florida, usa, is an especially vulnerable region because of high impacts from hydrological perturbations and nonindigenous species. to assess the extent of recent change in herpetofauna community composition, we established a baseline inventory during 1995-97 at a managed preserve in a habitat rich area of southwest florida, and repeated our sampling methods fifteen years later (2010-11). nine drift fence arrays were placed in fo ... | 2015 | 26016475 |
| a new species of eimeria schneider, 1875 (apicomplexa: eimeriidae) from the brown anole anolis sagrei duméril & bibron (sauria: dactyloidae) in florida, usa. | during july 2014, 14 brown anoles, anolis sagrei duméril & bibron were collected from orange county, florida, usa, and their faeces examined for coccidian parasites. one (7%) lizard harboured an eimerian that we describe here as new. oöcysts of eimeria garmani n. sp. were ellipsoidal with a uni-layered wall and measured 19.3 × 12.5 µm, with a length/width ratio of 1.5. a micropyle and oöcyst residuum were absent but 1-2 polar granule(s) were present. sporocysts were subspheroidal, 6.8 × 6.3 µm, ... | 2015 | 25962466 |
| molecular detection of invertebrate prey in vertebrate diets: trophic ecology of caribbean island lizards. | understanding community assembly and population dynamics frequently requires detailed knowledge of food web structure. for many consumers, obtaining precise information about diet composition has traditionally required sacrificing animals or other highly invasive procedures, generating tension between maintaining intact study populations and knowing what they eat. we developed 16s mitochondrial dna sequencing methods to identify arthropods in the diets of generalist vertebrate predators without ... | 2015 | 25545675 |
| rapid evolution of a native species following invasion by a congener. | in recent years, biologists have increasingly recognized that evolutionary change can occur rapidly when natural selection is strong; thus, real-time studies of evolution can be used to test classic evolutionary hypotheses directly. one such hypothesis is that negative interactions between closely related species can drive phenotypic divergence. such divergence is thought to be ubiquitous, though well-documented cases are surprisingly rare. on small islands in florida, we found that the lizard a ... | 2014 | 25342801 |
| natural selection on thermal performance in a novel thermal environment. | tropical ectotherms are thought to be especially vulnerable to climate change because they are adapted to relatively stable temperature regimes, such that even small increases in environmental temperature may lead to large decreases in physiological performance. one way in which tropical organisms may mitigate the detrimental effects of warming is through evolutionary change in thermal physiology. the speed and magnitude of this response depend, in part, on the strength of climate-driven selecti ... | 2014 | 25225361 |
| involvement of different mesotocin (oxytocin homologue) populations in sexual and aggressive behaviours of the brown anole. | the oxytocin (ot) family of neuropeptides are known to modulate social behaviours and anxiety in mammals and birds. we investigated cell numbers and neural activity, assessed as fos induction, within magnocellular and parvocellular populations of neurons producing the ot homologue mesotocin (mt, ile(8)-oxytocin). this was conducted within the male brown anole lizard, anolis sagrei, following agonistic or courtship encounters with a conspecific. both neurons colocalizing and not colocalizing cort ... | 2014 | 25165455 |
| the maternal environment affects offspring viability via an indirect effect of yolk investment on offspring size. | environmental conditions that reproductive females experience can influence patterns of offspring provisioning and fitness. in particular, prey availability can influence maternal reproduction and, in turn, affect the viability of their offspring. although such maternal effects are widespread, the mechanisms by which these effects operate are poorly understood. we manipulated the amount of prey available to female brown anole lizards (anolis sagrei) to evaluate how this factor affects patterns o ... | 2014 | 24642545 |
| neural activity in catecholaminergic populations following sexual and aggressive interactions in the brown anole, anolis sagrei. | social behaviors in vertebrates are modulated by catecholamine (ca; dopamine, norepinephrine, epinephrine) release within the social behavior neural network. few studies have examined activity across ca populations in relation to social behaviors. the involvement of cas in social behavior regulation is especially underexplored in reptiles, relative to other amniotes. in this study, we mapped ca populations throughout the brain (excluding retina and olfactory bulb) of the male brown anole lizard, ... | 2014 | 24472578 |
| physiological variation among invasive populations of the brown anole (anolis sagrei). | invasive species often encounter novel climatic conditions when they spread outside of their native ranges. invading populations can respond to novel conditions by acclimation or adaptation of physiological capacities, which may facilitate their spread. we investigated differences in physiological traits among three populations of an invasive lizard, the brown anole (anolis sagrei), along the latitudinal extent of its invasion in the southeastern united states. we predicted latitudinal clines fo ... | 2014 | 24457924 |
| dawn and dusk "chorus" in visually communicating jamaican anole lizards. | a key hypothesis explaining the existence of dawn and dusk choruses in acoustically communicating animals centers on the need to advertise continued territorial occupancy after and before a period of nocturnal inactivity. if this hypothesis is correct, it follows that similar dawn and dusk choruses should occur in territorial animals exploiting other signal modalities. adult male anolis lizards defend territories by using elaborate head-bobbing displays and extensions of a throat fan or dewlap. ... | 2008 | 18729743 |
| predators determine how weather affects the spatial niche of lizard prey: exploring niche dynamics at a fine scale. | although abiotic and biotic factors can interact to shape the spatial niche of a species, studies that explore the interactive effects of both at a local scale are rare. we demonstrate that one of the main axes (perch height) characterizing the spatial niche of a common lizard, anolis sagrei, varies according to the interactive effects of weather and the activity of a larger predatory lizard, leiocephalus carinatus. results were completely consistent: no matter how favorable the weather conditio ... | 2012 | 23431582 |
| aggression- and sex-induced neural activity across vasotocin populations in the brown anole. | activity within the social behavior neural network is modulated by the neuropeptide arginine vasotocin (avt) and its mammalian homologue arginine vasopressin (avp). however, central avt/avp release causes different behavioral effects across species and social environments. these differences may be due to the activation of different neuronal avt/avp populations or to similar activity patterns causing different behavioral outputs. we examined neural activity (assessed as fos induction) within avt ... | 2013 | 23201179 |
| transmission, host specificity, and seasonal occurrence of cyrtosomum penneri (nematoda: atractidae) in lizards from florida. | experimental infections and field-collected lizards were used to investigate issues of transmission, host specificity, and seasonal occurrence in the nematode cyrtosomum penneri (cosmocercoidea: atractidae). anolis sagrei (87 males, 42 females) were captured from the florida southern college campus, polk county, florida, from october 2010 to september 2011, and 8,803 c. penneri were collected from their intestines. during the breeding season all sexually mature (svl ≥ 34 mm) a. sagrei were infec ... | 2013 | 23020090 |
| an experimental test of the role of predators in the maintenance of a genetically based polymorphism. | polymorphisms provide one of the most useful tools for understanding the maintenance of genetic and phenotypic variation in nature. we have previously described a genetically based polymorphism in dorsal patterning that is expressed by female brown anole lizards, anolis sagrei, which occur in bar, diamond and intermediate diamond-bar morphs. previous studies of island populations in the bahamas support a role for selection in maintaining the polymorphism, but the agents responsible for this sele ... | 2012 | 22913414 |
| assessment of the mass, length, center of mass, and principal moment of inertia of body segments in adult males of the brown anole (anolis sagrei) and green, or carolina, anole (anolis carolinensis). | this study provides a morphometric data set of body segments that are biomechanically relevant for locomotion in two ecomorphs of adult male anoles, namely, the trunk-ground anolis sagrei and the trunk-crown anolis carolinensis. for each species, 10 segments were characterized, and for each segment, length, mass, location of the center of mass, and radius of gyration were measured or calculated, respectively. the radii of gyration were computed from the moments of inertia by using the double swi ... | 2012 | 22461036 |
| comprehensive primer design for analysis of population genetics in non-sequenced organisms. | nuclear sequence markers are useful tool for the study of the history of populations and adaptation. however, it is not easy to obtain multiple nuclear primers for organisms with poor or no genomic sequence information. here we used the genomes of organisms that have been fully sequenced to design comprehensive sets of primers to amplify polymorphic genomic fragments of multiple nuclear genes in non-sequenced organisms. first, we identified a large number of candidate polymorphic regions that we ... | 2012 | 22393396 |
| founder effects persist despite adaptive differentiation: a field experiment with lizards. | the extent to which random processes such as founder events contribute to evolutionary divergence is a long-standing controversy in evolutionary biology. to determine the respective contributions of founder effects and natural selection, we conducted an experiment in which brown anole (anolis sagrei) lizard populations were established on seven small islands in the bahamas, from male-female pairs randomly drawn from the same large-island source. these founding events generated significant among- ... | 2012 | 22300849 |
| is water uptake by reptilian eggs regulated by physiological processes of embryos or a passive hydraulic response to developmental environments? | moisture availability is critical for successful embryonic development in many organisms. in most oviparous reptiles, for example, water exchange between eggs and the surrounding environment can have substantial fitness consequences, but regulation of this process is unclear. here, we evaluate whether water uptake by eggs of the lizard anolis sagrei is regulated by the presence of a live embryo or is a passive hydraulic response to substrate moisture conditions. many eggs laid in our captive col ... | 2011 | 21820075 |
| does solitary incubation enhance egg water uptake and offspring quality in a lizard that produces single-egg clutches? | many organisms invariably produce one offspring per reproductive bout, but experimental tests of adaptive explanations for this reproductive pattern are rare. to address this issue, we studied a lizard (anolis sagrei) that produces one egg at a time to test the hypothesis that solitary incubation (due to single-egg clutches) eliminates competition with adjacent eggs for moisture and thus enhances offspring quality via increased egg water uptake during development. our findings suggest that solit ... | 2011 | 21370483 |
| human-induced morphological shifts in an island lizard. | understanding the evolutionary consequences of anthropogenic change is an emerging topic in evolutionary biology. while highly sensitive species may go extinct in response to anthropogenic habitat alteration, those with broader environmental tolerances may persist and adapt to the changes. here, we use morphological data from the brown anole (anolis sagrei), a lizard species that lives in both natural and human-disturbed habitats, to examine the impact of anthropogenic habitat alteration. we fin ... | 2011 | 25567980 |
| an experimental test for alternative reproductive strategies underlying a female-limited polymorphism. | polymorphism often corresponds to alternative mating tactics in males, but much less is known about this relationship in females. however, recent work suggests that selection for alternative reproductive strategies in females can maintain genetic variation in important life-history traits. brown anole lizards (anolis sagrei) exhibit a genetically based polymorphism in dorsal pattern that is expressed only by females, which occur in bar (b), diamond (d) and intermediate diamond-bar (db) morphs. h ... | 2011 | 21091569 |
| paternal condition drives progeny sex-ratio bias in a lizard that lacks parental care. | sex-allocation theory predicts that females in good condition should preferentially produce offspring of the sex that benefits the most from an increase in maternal investment. however, it is generally assumed that the condition of the sire has little effect on progeny sex ratio, particularly in species that lack parental care. we used a controlled breeding experiment and molecular paternity analyses to examine the effects of both maternal and paternal condition on progeny sex ratio and progeny ... | 2011 | 20731712 |
| marine subsidies have multiple effects on coastal food webs. | the effect of resource subsidies on recipient food webs has received much recent attention. the purpose of this study was to measure the effects of significant seasonal seaweed deposition events, caused by hurricanes and other storms, on species inhabiting subtropical islands. the seaweed represents a pulsed resource subsidy that is consumed by amphipods and flies, which are eaten by lizards and predatory arthropods, which in turn consume terrestrial herbivores. additionally, seaweed decomposes ... | 2010 | 20503874 |
| cryptic sex-ratio bias provides indirect genetic benefits despite sexual conflict. | when selection favors sexual dimorphism, high-fitness parents often produce low-fitness progeny of the opposite sex. this sexual conflict is thought to overwhelm the genetic benefits of mate choice because preferred males incur a cost through the production of low-fitness daughters. we provide a counterpoint in a lizard (anolis sagrei) that exhibits sexual conflict over body size. by using mate-choice experiments, we show that female brown anoles produce more sons than daughters via large sires ... | 2010 | 20203012 |
| severe costs of reproduction persist in anolis lizards despite the evolution of a single-egg clutch. | a central tenet of life-history theory is that investment in reproduction compromises survival. we tested for costs of reproduction in wild brown anoles (anolis sagrei) by eliminating reproductive investment via surgical ovariectomy and/or removal of oviductal eggs. anoles are unusual among lizards in that females lay single-egg clutches at frequent intervals throughout a lengthy reproductive season. this evolutionary reduction in clutch size is thought to decrease the physical burden of reprodu ... | 2010 | 19930451 |
| modeling and measuring the visual detection of ecologically relevant motion by an anolis lizard. | motion in the visual periphery of lizards, and other animals, often causes a shift of visual attention toward the moving object. this behavioral response must be more responsive to relevant motion (predators, prey, conspecifics) than to irrelevant motion (windblown vegetation). early stages of visual motion detection rely on simple local circuits known as elementary motion detectors (emds). we presented a computer model consisting of a grid of correlation-type emds, with videos of natural motion ... | 2010 | 19908049 |
| manipulating testosterone to assess links between behavior, morphology, and performance in the brown anole anolis sagrei. | abstract survival and reproductive success are determined by the complex interplay between behavior, physiology, morphology, and performance. when optimal trait combinations along these various phenotypic axes differ between sexes or across seasons, regulatory mechanisms such as sex steroids can often facilitate sex-specific and/or seasonal trait expression. in this study, we used surgical castration and replacement of exogenous testosterone in adult male brown anoles (anolis sagrei) to simultan ... | 2013 | 19673657 |
| geographic variation, frequency-dependent selection, and the maintenance of a female-limited polymorphism. | a central problem in evolutionary biology is to understand how spatial and temporal variation in selection maintain genetic variation within and among populations. brown anole lizards (anolis sagrei) exhibit a dorsal pattern polymorphism that is expressed only in females, which occur in "diamond,"bar," and intermediate "diamond-bar" morphs. to understand the inheritance of this polymorphism, we conducted a captive breeding study that refuted several single-locus models and supported a two-locus ... | 2010 | 19663989 |
| predation-associated modulation of movement-based signals by a bahamian lizard. | signaling individuals must effectively capture and hold the attention of intended conspecific receivers while limiting eavesdropping by potential predators. a possible mechanism for achieving this balance is for individuals to modulate the physical properties of their signals or to alter the proportion of time spent signaling, depending upon local levels of predation pressure. we test the hypothesis that prey can alter their visual signaling behavior to decrease conspicuousness and potentially l ... | 2014 | 24843163 |
| experimentally decoupling reproductive investment from energy storage to test the functional basis of a life-history trade-off. | the ubiquitous life-history trade-off between reproduction and survival has long been hypothesized to reflect underlying energy-allocation trade-offs between reproductive investment and processes related to self-maintenance. although recent work has questioned whether energy-allocation models provide sufficient explanations for the survival cost of reproduction, direct tests of this hypothesis are rare, especially in wild populations. this hypothesis was tested in a wild population of brown anol ... | 2014 | 24724820 |
| what determines dewlap diversity in anolis lizards? an among-island comparison. | animal signalling systems are extremely diverse as they are under different, often conflicting, selective pressures. a classic textbook example of a diverse signal is the anoline dewlap. both at the inter- and intraspecific levels, dewlap size, colour, shape and pattern vary extensively. here, we attempt to elucidate the various factors explaining the diversity in dewlap size and pattern among seven anolis sagrei populations from different islands in the bahamas. the seven islands differ in the ... | 2009 | 19196384 |
| experimental evidence that competition and habitat use shape the individual fitness surface. | a key prediction made by theories of density-dependent competition is that resource overlap should increase the intensity of competition. by extension, we can predict that competition should lead to density-dependent natural selection. i studied natural selection on limb length and body size in a total of seven populations of anolis sagrei over 3 years in the bahamas. experimental manipulations of population density on small off-shore cays revealed that the strength of natural selection on body ... | 2009 | 19120813 |
| habitat use and ecological interactions of an introduced and a native species of anolis lizard on grand cayman, with a review of the outcomes of anole introductions. | since its introduction ten years ago, anolis sagrei has spread over much of grand cayman and is now more common in some habitats than the native anole, a. conspersus. interspecific differences in body size, perch height, and microclimatic preference may have facilitated the colonization. nonetheless, competition may be occurring between the species; comparisons with studies of habitat use prior to the arrival of a. sagrei indicate that in open habitats, where a. sagrei is now abundant, a. conspe ... | 1993 | 28313293 |
| acoustical coupling of lizard eardrums. | lizard ears are clear examples of two-input pressure-difference receivers, with up to 40-db differences in eardrum vibration amplitude in response to ipsi- and contralateral stimulus directions. the directionality is created by acoustical coupling of the eardrums and interaction of the direct and indirect sound components on the eardrum. the ensuing pressure-difference characteristics generate the highest directionality of any similar-sized terrestrial vertebrate ear. the aim of the present stud ... | 2008 | 18648878 |
| admixture determines genetic diversity and population differentiation in the biological invasion of a lizard species. | molecular genetic analyses show that introduced populations undergoing biological invasions often bring together individuals from genetically disparate native-range source populations, which can elevate genotypic variation if these individuals interbreed. differential admixture among multiple native-range sources explains mitochondrial haplotypic diversity within and differentiation among invasive populations of the lizard anolis sagrei. our examination of microsatellite variation supports the h ... | 2008 | 18492644 |
| postcopulatory fertilization bias as a form of cryptic sexual selection. | males and females share most of their genetic material yet often experience very different selection pressures. some traits that are adaptive when expressed in males may therefore be maladaptive when expressed in females. recent studies demonstrating negative correlations in fitness between parents and their opposite-sex progeny suggest that natural selection may favor a reduction in trait correlations between the sexes to partially mitigate intralocus sexual conflict. we studied sex-specific fo ... | 2008 | 18298641 |
| differential fitness effects of immunocompetence and neighbourhood density in alternative female lizard morphs. | 1. a growing number of studies demonstrate that natural selection acts on traits important in whole animal performance and physiology. 2. here we describe a heritable polymorphism in female dorsal pattern in the lizard anolis sagrei (dumeril & bibron 1837). 3. morphs did not differ in body size or habitat use (perch diameter), however, we show that the social environment, estimated by the number of female neighbours, had different selective effects on alternative morphs in nature. 4. we show tha ... | 2008 | 18177330 |
| the quick and the dead: correlational selection on morphology, performance, and habitat use in island lizards. | natural selection is an important driver of microevolution. yet, despite significant theoretical debate, we still have a poor understanding of how selection operates on interacting traits (i.e., morphology, performance, habitat use). locomotor performance is often assumed to impact survival because of its key role in foraging, predator escape, and social interactions, and shows strong links with morphology and habitat use within and among species. in particular, decades of study suggest, but hav ... | 2007 | 17725626 |
| probing the adaptive landscape using experimental islands: density-dependent natural selection on lizard body size. | anolis lizards in the greater antilles are thought to have diversified through natural selection on body size and shape, presumably due to interspecific competition and variation in locomotor performance. here we measure natural selection on body size over three years and across seven replicate populations of the brown anole, a. sagrei. we experimentally manipulated an important component of the environment (population density) on several small islands to test the role of density in driving natu ... | 2007 | 17492960 |
| differential admixture shapes morphological variation among invasive populations of the lizard anolis sagrei. | the biological invasion of the lizard anolis sagrei provides an opportunity to study evolutionary mechanisms that produce morphological differentiation among non-native populations. because the a. sagrei invasion represents multiple native-range source populations, differential admixture as well as random genetic drift and natural selection, could shape morphological evolution during the invasion. mitochondrial dna (mtdna) analyses reveal seven distinct native-range source populations for 10 int ... | 2007 | 17402975 |
| contributions of pterin and carotenoid pigments to dewlap coloration in two anole species. | animals can acquire bright coloration using a variety of pigmentary and microstructural mechanisms. reptiles and amphibians are known to use two types of pigments - pterins and carotenoids - to generate their spectrum of colorful red, orange, and yellow hues. because both pigment classes can confer all of these hues, the relative importance of pterins versus carotenoids in creating these different colors is not always apparent. we studied the carotenoid and pterin content of red and yellow dewla ... | 2007 | 17056290 |
| phylogenetic analysis of the evolution of the niche in lizards of the anolis sagrei group. | recent advances in ecological niche modeling (enm) algorithms, in conjunction with increasing availability of geographic information system (gis) data, allow species' niches to be predicted over broad geographic areas using environmental characteristics associated with point localities for a given species. consequently, the examination of how niches evolve is now possible using a regionally inclusive multivariate approach to characterize the environmental requirements of a species. initial work ... | 2006 | 16922300 |
| astroglial cells in the central nervous system of the adult brown anole lizard, anolis sagrei, revealed by intermediate filament immunohistochemistry. | we analyzed the distribution of intermediate filament molecular markers, glial fibrillary acidic protein (gfap), and vimentin in the brain and spinal cord of the adult brown anole lizard, anolis sagrei. the gfap immunoreactivity is strong and the positive structures are basically represented by fibers of different lengths and thicknesses which are arranged in a regular radial pattern throughout the central nervous system. in the brain regions that have a thicker neural wall, the radial orientati ... | 2005 | 16086399 |
| ultraviolet exposure and vitamin d synthesis in a sun-dwelling and a shade-dwelling species of anolis: are there adaptations for lower ultraviolet b and dietary vitamin d3 availability in the shade? | we compared the natural ultraviolet b (uv-b) exposure, dietary vitamin d, and skin-generated vitamin d synthesis for adult males of two species of jamaican anoles. the more shade-tolerant and thermal-conforming anolis lineotopus merope, rarely exposed to full sun, experienced less uv-b irradiation in its shady environment than the more heliophilic and thermophilic anolis sagrei, which frequently basked in full sun during the morning hours (0800-1100 hours). both species obtained detectable level ... | 2006 | 15778939 |
| genetic variation increases during biological invasion by a cuban lizard. | a genetic paradox exists in invasion biology: how do introduced populations, whose genetic variation has probably been depleted by population bottlenecks, persist and adapt to new conditions? lessons from conservation genetics show that reduced genetic variation due to genetic drift and founder effects limits the ability of a population to adapt, and small population size increases the risk of extinction. nonetheless, many introduced species experiencing these same conditions during initial intr ... | 2004 | 15356629 |
| gender and spatial patterns in metal concentrations in brown anoles (anolis sagrei) in southern florida, usa. | comparatively little is known about heavy metal levels in reptiles, particularly for lizards. yet lizards often are common predators that could serve as bioindicators of contamination on a small spatial scale. this study examined the differences in metal concentrations of adult brown anoles (anolis sagrei) for arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in six locations in southern florida, usa, from lake okeechobee (pahokee) south to key west. we predicted that levels of ... | 2004 | 15285365 |
| the effects of surface diameter and incline on the hindlimb kinematics of an arboreal lizard (anolis sagrei). | arboreal animals often move in habitats with dense vegetation, narrow perches and variable inclines, but effects of arboreal habitat structure on locomotor function are poorly understood for most animals. several species of anolis lizards, which have served as a model group for relating locomotor performance to morphology, have decreased maximal sprinting speeds when perch diameter decreases. however, the effects of perch diameter on the limb movements of anolis have not been previously studied. ... | 2004 | 15143145 |
| effect of immersion in seawater on egg survival in the lizard anolis sagrei. | studies on the lizard, anolis sagrei, revealed that after hurricane floyd devastated the bahamas in 1999, some populations consisted only of hatchlings. because the storm surge of the hurricane completely inundated these islands, apparently for up to 6 h, survival of anole eggs in salt water for such periods is implied. to test this hypothesis directly, we placed a. sagrei eggs in saltwater for 3 or 6 h with unimmersed eggs serving as the control. hatching success and incubation time did not dif ... | 2003 | 12910410 |
| the effect of oxygen and adenosine on lizard thermoregulation. | a regulated decrease in internal body temperature (tb) appears to play a protective role against metabolic disruptions such as exposure to ambient hypoxia. this study examined the possibility that tb depression is initiated when low internal oxygen levels trigger the release of adenosine, a neural modulator known to influence thermoregulation. we measured selected tb of anolis sagrei in a thermal gradient under varied ambient oxygen conditions and following the administration of the adenosine re ... | 2013 | 12905120 |
| effects of testosterone treatment and season on the frequency of dewlap extensions during male-male interactions in the lizard anolis sagrei. | lizards of the genus anolis extend and retract a large and often brightly colored throat fan called a dewlap. the dewlap in most anoles is a sexually dimorphic structure. it is larger in males than females and males use the dewlap more frequently and in more contexts than do females. in the present study we investigated whether plasma testosterone (t) levels and season affect the frequency of dewlap use in male--male interactions in the brown anole, anolis sagrei. we manipulated plasma t levels ... | 2002 | 11863385 |
| testosterone, growth and the evolution of sexual size dimorphism. | the integration of macroevolutionary pattern with developmental mechanism presents an outstanding challenge for studies of phenotypic evolution. here, we use a combination of experimental and comparative data to test whether evolutionary shifts in the direction of sexual size dimorphism (ssd) correspond to underlying changes in the endocrine regulation of growth. first, we combine captive breeding studies with mark-recapture data to show that male-biased ssd develops in the brown anole lizard (a ... | 2009 | 19549143 |
| sex-specific adult dispersal and its selective consequences in the brown anole, anolis sagrei. | 1. dispersal behaviour is a potentially risky life-history strategy that can impact habitat use as well as competition over territories and mates. 2. i studied natural selection on dispersal behaviour over the course of four breeding seasons in a bahamian population of brown anoles (anolis sagrei). 3. both males and females showed extremely high site fidelity over the course of each reproductive season. movement distance in males was negatively correlated with body size at first capture in sprin ... | 2009 | 19302322 |
| otoacoustic emissions, hair cells, and myosin motors. | the stereovillar bundles of hair cells show active movements that may be generated by the putative myosin-actin interactions underlying hair-cell adaptation. such movement is a possible candidate for the generation of spontaneous otoacoustic emissions (soae) in the ear canal of nonmammals. in the basilar papilla of certain lizard families, most hair cells are not coupled by a tectorial membrane, making it easier to assign the energy in emission peaks to defined groups of hair cells. we have stud ... | 1997 | 9265753 |
| effects of corticosterone treatment on male aggressive behavior in a lizard (anolis sagrei). | social dominance in several species of lizards appears related to adrenal gland activity. the purpose of this study was to test whether the adrenal hormone corticosterone (cs) would inhibit the aggressive behavior of males of the lizard anolis sagrei. reproductively active males were randomly assigned to either cs or placebo (p) treatment groups or to an untreated stimulus male group. both cs and p were administered in pellet form. corticosterone pellets were designed to release approximately 4. ... | 1987 | 3666688 |
| effects of the antiandrogens cyproterone acetate and flutamide on male reproductive behavior in a lizard (anolis sagrei). | this study examined the effects of the antiandrogens cyproterone acetate (ca) and flutamide (f) on male reproductive behavior in the lizard anolis sagrei. reproductively active males were implanted with subcutaneous pellets of either ca, f, or placebo (p). pellets delivered ca and f at a constant rate of 0.1 mg/day. three weeks after implantation, males were tested with stimulus males and two days later with stimulus females. cyproterone acetate inhibited aspects of male aggressive and sexual be ... | 1987 | 3557326 |
| hormonal regulation of male reproductive behavior in the lizard anolis sagrei: a test of the aromatization hypothesis. | this study examined the hypothesis that aromatization of testosterone (t) to estradiol (e) is required to activate reproductive behavior in castrated male lizards (anolis sagrei). adult, reproductively active males were assigned to an intact control group or to one of four treatment groups. treatment males were castrated and 1 week later three of the four castrated groups were implanted with subcutaneous pellets containing either 0.05 mg of e, 0.5 mg of t, or 0.5 mg of dihydrotestosterone (dht). ... | 1986 | 3770658 |
| experiments on dispersal: short-term floatation of insular anoles, with a review of similar abilities in other terrestrial animals. | the floatation ability of a common carribean insular lizard, anolis sagrei, was tested under controlled conditions in a laboratory seawater wave tank. short-term passive floatation abilities are extensive: all 39 animals survived 1 h, and 30% of those tested were still afloat by 24 h.the survival times for anoles in seawater are much greater than those reported in the literature for the 19 species of small mammals tested in freshwater; only mediumsized mammals have comparable abilities. floatati ... | 1984 | 28311201 |
| the importance of species: pygmy rattlesnake venom toxicity differs between native prey and related non-native species. | venom toxicity assessments are often based upon non-native surrogate prey species that are not consumed in the wild by the venomous predator. this raises questions about the relevance of toxicity results on these "model" prey in addressing ecological or evolutionary questions about venom effects on native prey. we explore this issue by comparing the toxicity of venom from pygmy rattlesnakes (sistrurus miliarius) on taxonomically-diverse sets of model (non-native) and native prey. specifically, w ... | 2018 | 29410327 |
| maternal allocation of carotenoids to eggs in an anolis lizard. | the maternal allocation of carotenoids to eggs has been widely documented and manipulated. however, it is often assumed that the sole adaptive value of this allocation is to increase offspring fitness. because carotenoids can be pro-oxidants or antioxidants depending on their concentrations and their chemical environment (i.e. presence of other antioxidants), dams may need to dispose of excess carotenoids upon depletion of other antioxidants to prevent oxidative damage. additionally, the amount ... | 2018 | 29410189 |
| artificial light at night increases growth and reproductive output in anolis lizards. | since the invention of electric lighting, artificial light at night (alan) has become a defining, and evolutionary novel, feature of human-altered environments especially in cities. alan imposes negative impacts on many organisms, including disrupting endocrine function, metabolism, and reproduction. however, we do not know how generalized these impacts are across taxa that exploit urban environments. we exposed brown anole lizards, an abundant and invasive urban exploiter, to relevant levels of ... | 2020 | 31964308 |
| seasonal changes of host use by culiseta melanura (diptera: culicidae) in central florida. | the mosquito culiseta melanura (coquillett) is the primary enzootic vector of eastern equine encephalitis virus (eeev), a zoonotic alphavirus endemic to eastern north america. in its northern range, cs. melanura is considered a strict avian biter, transmitting eeev among susceptible birds in a cycle of enzootic amplification. in its southern range, however, cs. melanura is more general in host use, feeding heavily upon birds but also reptiles and mammals. the goal of this study was to better und ... | 2020 | 32280994 |
| phylogeographic and phenotypic outcomes of brown anole colonization across the caribbean provide insight into the beginning stages of an adaptive radiation. | some of the most important insights into the ecological and evolutionary processes of diversification and speciation have come from studies of island adaptive radiations, yet relatively little research has examined how these radiations initiate. we suggest that anolis sagrei is a candidate for understanding the origins of the caribbean anolis adaptive radiation and how a colonizing anole species begins to undergo allopatric diversification, phenotypic divergence and, potentially, speciation. we ... | 2019 | 31872929 |
| distal spinal nerve development and divergence of avian groups. | the avian transition from long to short, distally fused tails during the mesozoic ushered in the pygostylian group, which includes modern birds. the avian tail embodies a bipartite anatomy, with the proximal separate caudal vertebrae region, and the distal pygostyle, formed by vertebral fusion. this study investigates developmental features of the two tail domains in different bird groups, and analyzes them in reference to evolutionary origins. we first defined the early developmental boundary b ... | 2020 | 32286419 |
| crispr-cas9 gene editing in lizards through microinjection of unfertilized oocytes. | crispr-cas9-mediated gene editing has enabled the direct manipulation of gene function in many species. however, the reproductive biology of reptiles presents unique barriers for the use of this technology, and there are no reptiles with effective methods for targeted mutagenesis. here, we demonstrate that the microinjection of immature oocytes within the ovaries of anolis sagrei females enables the production of crispr-cas9-induced mutations. this method is capable of producing f0 embryos and h ... | 2019 | 31461646 |
| host associations of culex (melanoconion) atratus (diptera: culicidae) and culex (melanoconion) pilosus from florida, usa. | characterizing the host-use patterns of mosquitoes is an essential component of understanding the transmission dynamics of mosquito-vectored pathogens. the host associations of two species of the medically important culex subgenus melanoconion, culex atratus, and culex pilosus are unknown or unclear, respectively. both species have wide neotropical distributions. in the united states of america (usa), culex pilosus occurs throughout the southeastern coastal plain, while culex atratus is restrict ... | 2019 | 31382597 |
| establishment of brown anoles (anolis sagrei) across a southern california county and potential interactions with a native lizard species. | the brown anole, anolis sagrei, is a native species to the caribbean; however, a. sagrei has invaded multiple parts of the usa, including florida, louisiana, hawai'i and more recently california. the biological impacts of a. sagrei invading california are currently unknown. evidence from the invasion in taiwan shows that they spread quickly and when immediate action is not taken eradication stops being a viable option. in orange county, california, five urban sites, each less than 100 ha, were s ... | 2020 | 32296613 |
| the epigenetic signature of colonizing new environments in anolis lizards. | founder populations often show rapid divergence from source populations after colonizing new environments. epigenetic modifications can mediate phenotypic responses to environmental change and may be an important mechanism promoting rapid differentiation in founder populations. whereas many long-term studies have explored the extent to which divergence between source and founder populations is genetically heritable versus plastic, the role of epigenetic processes during colonization remains uncl ... | 2019 | 31147693 |
| character displacement in the midst of background evolution in island populations of anolis lizards: a spatiotemporal perspective. | negative interactions between species can generate divergent selection that causes character displacement. however, other processes cause similar divergence. we use spatial and temporal replication across island populations of anolis lizards to assess the importance of negative interactions in driving trait shifts. previous work showed that the establishment of anolis sagrei on islands drove resident anolis carolinensis to perch higher and evolve larger toepads. to further test the interaction's ... | 2020 | 32786005 |
| enhanced locomotor performance on familiar surfaces is uncoupled from morphological plasticity in anolis lizards. | 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 ... | 2020 | 31994351 |
| asymmetric interference competition and niche partitioning between native and invasive anolis lizards. | species can compete both directly via aggressive encounters (interference) and indirectly through their shared use of a limited resource (exploitation). depending on the circumstances interference, exploitation, and their interplay can either lead to competitive exclusion or drive niche partitioning to maintain species coexistence. thus, understanding species coexistence in nature requires accurately identifying the mechanisms that contribute to competition among the species in question. in the ... | 2019 | 31312905 |
| predator-induced collapse of niche structure and species coexistence. | biological invasions are both a pressing environmental challenge and an opportunity to investigate fundamental ecological processes, such as the role of top predators in regulating biodiversity and food-web structure. in whole-ecosystem manipulations of small caribbean islands on which brown anole lizards (anolis sagrei) were the native top predator, we experimentally staged invasions by competitors (green anoles, anolis smaragdinus) and/or new top predators (curly-tailed lizards, leiocephalus c ... | 2019 | 31168105 |