Download or read book Field Studies on the Territorial Behavior of the Western Fence Lizard Sceloporus Occidentalis written by Lea Anne Sheldahl and published by . This book was released on 1999 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Neuroethological Study of Ritualized Aggressive Behavior in the Western Fence Lizard Sceloporus Occidentalis written by Robert Stuart Tarr and published by . This book was released on 1971 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Field Studies of the Behavior of the Lizard Sceloporus Spinosus Floridanus written by Horatio Hackett Newman and published by . This book was released on 1909 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Use of Patchy Early Successional Slope Habitat Along Coastal Sun facing Beaches by the Western Fence Lizard Sceloporus Occidentalis at the Species Northern Geographic Extreme written by Paul Backus and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comparisons among core and peripheral populations of animals for patterns of habitat use may be an important step in an area of ecological research: the quest to understand the mechanisms underlying species range boundaries. My research on the Western Fence Lizard, Sceloporus occidentalis, at the northwestern edge of the species' geographic range, is intended to lay the groundwork for future analyses of peripheral populations. Sceloporus occidentalis is a propitious species for studying peripheral animal populations because (1) relative to dryland habitats more typical of the species nearer the core of its geographic range, the peripheral population resides in a relatively unique beach-edge maritime habitat, and (2) it is found in high local abundance, is easy to observe and capture, and has low vagility relative to birds and mammals. My research addresses the habitat preferences, dispersal tendencies, and spatial distribution among individuals of S. occidentalis in a population at the species geographic extreme in western Washington. In 2013-2014 I captured, measured, and marked 359 lizards on the central beach in an apparent metapopulation along the Washington coast west of Marysville, WA. I recorded detailed habitat characteristics for every 10-meter stretch of beach using the line-intercept method (transect was set perpendicular to beach edge) and used Multidimensional Scaling analysis to correlate habitat characteristics with lizard sighting locations, thereby determining which sections of coastal beach edge were most heavily used by fence lizards. Similarity Percentage (SIMPER) analysis was used to determine which habitat characteristics were associated with most of the difference between occupied and unoccupied habitat areas. These characteristics and their relative influences on habitat differences were: distance to nearest patch of sun-exposed soil on the slope above the beach (45%), the abundance of nanohabitats (i.e. different substrata or log surfaces) in the log field below the slope (22%), the number of exposed soil patches on the beach slope (16%), the length (between slope base and beach-edge) of the log field on the beach below the slope (10%), and the relative amount of exposed soil in standard plots on the slope above the beach (5%). Chi-square analysis revealed that lizards were more likely to bask on log surfaces than on sand and leaf litter surfaces, perhaps because (1) body temperature can be more finely regulated on logs by adjusting angle of the body towards the sun, and (2) antipredator cover is nearer when on a log. Hatchling lizards were more likely than adults to be found on sand substratum. Based on proportions of age and sex classes that dispersed and the distances moved, I inferred that younger lizards were more likely to disperse longer distances than adults along Spee-Bi-Dah beach. Lizard sighting locations were documented in ArcGIS and the degree of overlap in habitat characteristics with lizard locations determined through Analysis of Similarity, which revealed lizards to be clumped around patches of prime habitat. A reasonable inference is that high population density and intraspecific competition in these habitat patches may be pushing lizards to disperse into suboptimal habitat. However, invasive plant species, particularly Himalayan blackberry, rapidly colonize open soil patches on the beach slope, restricting the lizards' access to habitat necessary for nesting and hibernation, and reducing habitat available for population growth or range expansion. Habitat degradation by invasive species and humans is likely a significant factor in the apparent decline of fence lizard populations along the Washington coast.

Download or read book The Evolutionary Ecology of Morphological Variation Within Populations of the Western Fence Lizard Sceloporus Occidentalis written by Kenneth John Halama and published by . This book was released on 1998 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Territory Establishment and Maintenance in the Western Fence Lizard Sceloporus Occidentalis and the Side blotched Lizard Uta Stansburiana as Determined with Time lapse Imaging written by Mark Kameron Roth and published by . This book was released on 2016 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Taxonomic and Evolutionary Study of the Western Fence Lizard Sceloporus Occidentalis and Its Relationships to the Eastern Fence Lizard Sceloporus Undulatus written by Edwin Lewis Bell and published by . This book was released on 1954 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A field study of the growth and behavior of the fence lizard written by Henry Sheldon Fitch and published by . This book was released on 1940 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hormones and Aggressive Behavior written by Bruce B. Svare and published by Springer Science & Business Media. This book was released on 2013-03-07 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is an overview of research examining the relationship between hormones and aggressive behavior. The last 15 years have witnessed a tremen dous growth of knowledge in this area, yet reviews written by specialists are virtually nonexistent. This work is an attempt to provide a comprehensive and cohesive synthesis of this literature. Chapters 1-7 provide an analysis of hor monal influences on the major forms of aggressive behavior, including intermale, interfemale, shock-induced, maternal, territorial, and predatory aggression. The focus of Chapters 8-12 is an examination of the mechanisms through which hormones might act to produce changes in agonistic responding. Genetic, de velopmental, neural, and biochemical influences are considered. It is well known that environment, social context, and experience modulate the effects of hor mones on behavior. Thus, Chapters 13-15 are designed to review the literature concerning hormone-pheromone interactions, hormonal responses to compe tition, and the influence of social context on the endocrine system and aggressive behavior. Frequently, the principles advanced by behavioral endocrinologists are based on research in one species, the rodent. To provide a more comparative perspective and to examine specifically the generality of those principles gen erated for rodents, Chapters 16-22 examine hormone-aggression relationships in a variety of species, including fish, birds, amphibians, reptiles, infrahuman primates, humans, ungulates, and insects. This volume should be useful to both beginning and advanced researchers in animal behavior, behavioral endocri nology, physiological psychology, neuroendocrinology, zoology, physiology, and psychiatry.

Download or read book Thermal Ecology of the Western Fence Lizard Sceloporus Occidentalis written by Samuel M. McGinnis and published by . This book was released on 1965 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Testosterone on the Spatial Ecology Coloration and Brain Regions in Western Fence Lizard Sceloporus Occidentalis written by Rachel Catharine Wilson and published by . This book was released on 2015 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: An organism’s spatial ecology allows for access to essential resources such as food, mates, and escape from predators. Home range size, or the total area an organism inhabits, varies in relation to numerous factors including seasonality. During the breeding season, home range size increases in males across taxa. In addition, males usually also have larger home range sizes than females. This implicates testosterone (T) as a possible mediator of this relationship. Indeed, T causes an increase in home range size of males in numerous species of lizards. In addition to T causing an increase in home range size, it also causes an increase in coloration, which is used as a signal to deter or elicit aggressive behaviors in lizards. Potentially, contests are less common in natural settings than in the lab due to this signaling despite increased frequency overlap of home ranges in males. The larger the home range size of males, mediated through an increase in T, the more overlap with conspecifics. With this increase in spatial demand, or home range size, there is often a corresponding increase in spatially related brain regions. In reptiles, these brain regions are the medial and dorsal cortices (MC and DC respectively). The increase in cortical brain region size due to an increase in spatial demand may be mediated by an increase in neurogenesis. Proliferation of neurons occurs along the ventricles and radiate to numerous regions in the brain including the MC. With respect to the MC, immature neurons, which express the protein doublecortin (DCX), migrate from the ventricles, through the inner plexiform layer and are integrated into the cell layer. Because DCX is only expressed in recently born, migrating neurons, it can be used to measure neurogenesis. In mammals and birds, neurogenesis and growth of certain brain regions is affected by steroid hormones, including T. Here we tested two hypotheses: (1) T affects the home range size of Sceloporus occidentalis and (2) cortical brain region volumes are related to home range size and/or T which is mediated through changes in rates of neurogenesis. We surgically castrated individuals and implanted subjects with either a T-filled implant or blank implant and then released them at their initial capture sites. In addition to these castrated individuals, subjects not subjected to castration served as unmanipulated controls. Home range size of individuals in the field was quantified using a global positioning system (GPS) unit and later delineating those GPS points using minimum convex polygons (MCPs). We predicted that (1) castrated, T-treated lizards and unmanipulated control lizards would have larger home range sizes than castrated, control lizards c and (2) MC and DC cortices would be larger in volume and contain more DCX-immunoreactive cells in the lizards with the highest circulating T levels and with the largest home range sizes. We found that increased T caused an increase in the number of blue abdominal scales. We found no differences in home range size relating to T. Likewise, T did not affect MC volumes. However, we did observe a decrease in DC volume with increasing plasma levels of T. Because T did not affect home range size, it follows that we did not find an effect of T on MC volume. However, the significant result of T causing a decrease in DC volume implies a possible trade off with regards to energetics and the maintenance of brain region volumes as prior research indicates that T in increases energy expenditure and decreases foraging efforts.

Download or read book Home Range and Territorial Behavior of the Lizards Sceloporus Occidentalis and Sceloporus Graciosus in the San Bernardino Mountains written by David Ward Stevens and published by . This book was released on 1973 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Red Mountains Wilderness Study Area WSA Arcata Resource Area Preliminary Wilderness Recommendation written by and published by . This book was released on 1988 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Behavior of Lizards written by Vincent Bels and published by CRC Press. This book was released on 2019-02-06 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: Key features: Presents a contemporary snapshot of the mechanisms underlying the evolution and adaptation of behavior Explores how genetics, epigenetics, development, and environment shape behavior Discusses a broad range of behavioral repertoires and responses, including those related to thermoregulatory, foraging, predatory, displaying, social and escape strategies. Examines physiological and sensory mechanisms Covers the effects of various aspects of global change on behavior, with chapters that focus on the impacts of climate change on hydroregulatory behavior and behavioral responses to the effects of habitat alteration resulting from human-mediated change and colonization by invasive species. Lizards serve as focal organisms for many of biological questions related to evolution, ecology, physiology, and morphology. They are studied at multiple spatial and temporal scales, from the individual to the community level. This book, authored by expert contributors from around the world, explores behaviors underlying the evolution and adaptation of these organisms. It covers conceptual, empirical, and methodological approaches to the understanding of the role that natural and sexual selection play in molding the behavioral traits of lizards. This thorough, illustrated reference should stimulate discussion of the conceptual and methodological approaches for studying the behavioral traits of these fascinating and highly diverse vertebrates.

Download or read book Diversification and Local Adaptation in Western Fence Lizards Sceloporus Occidentalis written by Nassima Mahdjouba Bouzid and published by . This book was released on 2019 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: I am fascinated by intraspecific variation-by both its sources and its potential implications for how organisms interact with their environments. The importance of intraspecific variation for predicting species responses to climate change has recently become a research priority. Differences in the sources of intraspecific variation0́3genetic divergence, phenotypic plasticity, and drift0́3can have profoundly different outcomes for species responses. Variation in traits produced by heritable differences in genes will be sensitive to future selection, while variation produced by phenotypic plasticity may be buffered. Time and again, mechanistic studies of species responses have highlighted the importance of considering trait variation to predict idiosyncratic responses, and the sources of trait variation must also be considered. I studied intraspecific variation in Western Fence Lizards (Sceloporus occidentalis) at three spatial scales and three levels of organization. In Chapter 1 I investigated species-wide phylogeographic patterns and demographic scenarios throughout western North America. In Chapter 2 I characterized clinal variation in genotypes and phenotypes and gene flow along an elevation gradient in Yosemite National Park. In Chapter 3 I disentangled the genetic and plastic constituents of divergent phenotypes in a lab rearing experiment. My dissertation research provides an integrative framework for studying local adaptation in a polymorphic and well-established vertebrate system. Chapter 1 is the culmination of over two decades of research on phylogeographic structure within S. occidentalis. We sampled 108 individuals from 83 localities throughout the range in western North America. We used 4,555 SNPs from ddRADseq to characterize population structure and estimate demographic history. We found five genetically distinct populations including: one in the southwest, south of the Transverse Ranges; two west of the Sierra Nevada-Cascades cordillera, separated from north-to-south just north of San Francisco Bay; and two east of the Sierra Nevada-Cascades cordillera, separated from east-to-west in the Great Basin desert. The branching pattern of populations suggests that populations south of the Transverse Ranges and west of the Sierra Nevada-Cascades cordillera are divergent from populations east of the Sierra Nevada-Cascades cordillera. The predominant mechanism of population divergence is allopatric divergence and contemporary secondary contact, which supports Quaternary glacial cycles as drivers of intraspecific genetic divergence. Chapter 2 builds on foundational work by Leaché et al. (2010) to characterize genetic and phenotypic clines along an elevation gradient in Yosemite National Park. At high elevations lizards are larger and more melanistic, while at low elevations lizards are smaller and lighter-colored. We sampled 78 individuals from a 21 km stretch of the Grand Canyon of the Tuolumne River in northern Yosemite. The elevation gradient spanned 1321 m from N Hetch Hetchy Reservoir (37.9168 N, 119.6595 W, 1167 m) in the west to E Glen Aulin (37.9076 N, 119.4196 W, 2488 m) in the east. We used 721 SNPs from ddRADseq to characterize genetic clines and estimate demographic history of populations along the elevation gradient. We found evidence for additional population structure and genetic divergence between phenotypically divergent individuals; one genetically distinct population corresponds to low elevation individuals and another corresponds to high elevation individuals. Analyses of SNPs, maximum size (snout-vent length, SVL), and coloration (ventral patch area) confirm that genes and phenotypes vary clinally, and not discretely, along the elevation gradient. Genetically distinct populations diverged in allopatry, but contemporary gene flow between populations is asymmetric. Genes flow uphill, with five times as many migrants entering the high elevation population from low elevation than the converse. Chapter 3 delves into the underlying sources of trait divergence between low and high elevation individuals from the Grand Canyon of the Tuolumne River elevation gradient. While low and high elevation lizards mature at the same age, high elevation lizards are larger and more melanistic than low elevation lizards. We disentangled the genetic and environmental constituents of phenotypic variation by rearing hatchling lizards under controlled lab conditions. We collected five gravid females from low elevation (N Hetch Hetchy Reservoir [37.96 N, -119.78 W, ca. 1200 m]) and eight gravid females from high elevation (Glen Aulin [37.91 N, -119.42 W, ca. 2400 m]), who produced 36 and 51 hatchling lizards, respectively. We evenly distributed hatchlings from both populations among two treatments that varied in potential activity time: short activity period (6 hrs) and long activity period (12 hrs). We varied activity time by limiting access to heat-lamp-produced thermal gradients, which are necessary for thermoregulation. We found evidence that differences in size are genetically-based; high elevation hatchlings were larger than low elevation hatchlings, regardless of treatment. We found evidence that differences in color are at least partially produced by phenotypic plasticity; high elevation hatchlings were capable of plastically lightening to a color that was lighter than low elevation hatchlings. We found evidence that differences in behavior are genetically-based; high elevation hatchlings spent more time engaged in active behaviors. Overall, our findings are suggestive of local adaptation of high elevation hatchlings to restricted activity periods at high elevation.

Download or read book A Comparison of the Demography and Female Reproduction in Sympatric Western Fence Lizards Sceloporus Occidentalis and Sagebrush Lizards Sceloporus Graciosus on Mount Diablo California written by Stephen Bennett Ruth and published by . This book was released on 1977 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Ecosystem on Microhabitat Use and Morphology of Western Fence Lizards Sceloporus Occidentalis written by Robert P. Pelletier and published by . This book was released on 2018 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Western Fence lizards (Sceloporus occidentalis) are a geographically widespread species that would benefit from adapting their microhabitat use and morphology to better suit the local habitat types they inhabit. To test for such differences, I used visual encounter surveys to assess the microhabitat use of the lizards and collected morphological data to evaluate differences between populations in different habitats. I observed the lizards at three sites representing three habitat types, including a suburban road in Turlock, Stanislaus Co., CA; a rocky cliff in Knights Ferry Recreational Area, Stanislaus Co., CA; and a Riparian forest in Caswell Memorial State Park, Ripon, San Joaquin Co., CA. My prediction that suburban road lizards would be generalists was supported; however, while there was evidence for morphological adaptation for reduced climbing ability and small body size, there was not support for improved running speed to facilitate escape to dense vegetated shelters. My prediction that rocky cliff lizards would be rock specialists was supported; the data showed adaptations for improved running, jumping, and climbing abilities on flat rocks along with a compressed body for taking refuge in tight rock crevices. My prediction that riparian forest lizards would specialize in using the tree microhabitat was not supported; as a result, my prediction that their morphology would be adapted for running, jumping, and broad tree climbing was disproven although they did exhibit a robust body. Instead the riparian forest population appeared better adapted for crypsis while making use of leaf litter and twigs on the ground. My results suggest that Western Fence Lizard populations do have shifts in microhabitat use in different habitat types and have means of adjusting their morphology to better suit their environment, be it through local adaptation or phenotypic plasticity.