Life Sciences Commons^™

Ectotherm Thermoregulation At Fine Scales: Novel Methods Reveal A Link Between The Spatial Distribution Of Temperature And Habitat Quality, Ian Axsom

Master's Theses

Investigating ecological questions at the scale of individual organisms is necessary to understand and predict the biological consequences of environmental conditions. For small organisms this can be challenging because we need tools with the appropriate accuracy and resolution to record and quantify their ecological interactions. Unfortunately, many of our existing tools are only appropriate for medium to large organisms or those that are wide ranging, inhibiting our ability to investigate the ecology of small organisms at fine scales.

In Chapter 1, I tested a novel workflow for recording animal movements at very fine spatial and temporal scales. The workflow combined …

Stop, Then Go! Rapid Acceleration Offsets The Costs Of Intermittent Locomotion When Turning In Florida Scrub Lizards, Cheyenne Walker

Electronic Theses and Dissertations

Intermittent locomotion is a commonly used escape strategy with a wide array of potential benefits. Pausing may aid in locating a predator, crypsis, lowering energy costs, and avoiding obstacles. Turning may also benefit from intermittent locomotion by allowing an animal time to assess its surroundings; therefore, decreasing the chances of making a mistake and/or stumbling. Florida scrub lizards live in environments with a variety of obstacles such as turns. The goal of this study is to quantify the locomotor behavior and performance by lizards while navigating a 45° or 90° turn. Lizards were run along both a 45° and 90° …

Habitat Heterogeneity Affects The Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Nicole Gaudenti

Master's Theses

Global climate change is already contributing to the extirpation of numerous species worldwide, and sensitive species will continue to face challenges associated with rising temperatures throughout this century and beyond. It is especially important to evaluate the thermal ecology of endangered ectotherm species now so that mitigation measures can be taken as early as possible. A recent study of the thermal ecology of the federally endangered Blunt-Nosed Leopard Lizard (Gambelia sila) suggested that they face major activity restrictions due to thermal constraints in their desert habitat, but that large shade-providing shrubs act as thermal buffers to allow them …

Reproductive Trade-Offs In The Colorado Checkered Whiptail Lizard (Aspidoscelis Neotesselatus): An Examination Of The Relationship Between Clutch And Follicle Size, Hannah E. Caracalas, S. S. French, S. B. Hudson, B. M. Kluever, A. C. Webb, D. Eifler, A. J. Lehmicke, Lise M. Aubry

USDA Wildlife Services: Staff Publications

Life history theory predicts that there should be an inverse relationship between offspring size and number, because individuals cannot simultaneously maximize both when resources are limited. Although extensively studied in avian species, the occurrence and determinants of reproductive tradeoffs in oviparous reptiles are far less understood, particularly in parthenogenetic species. We studied this trade-off in the Colorado Checkered Whiptail, Aspidoscelis neotesselatus, a female-only parthenogenetic lizard. Using data previously collected in 2018 and 2019, we tested for clutch and egg size trade-offs and determined whether this relationship could be influenced by female size and aspects of physiological condition. Physiological condition …

Sexual Dimorphism Of Thermal Preference In Florida Scrub Lizards (Sceloporus Woodi) And Predicting Response To Climate Change In Two Rare Habitats, Sidney E. Anderson

Electronic Theses and Dissertations

The Florida Scrub Lizard (Sceloporus woodi) is endemic to Florida, where it inhabits fragments of xeric sandhill uplands including endangered long-leaf pine and sand pine scrub habitats. Lizards depend on a predictable range of temperatures to maximize their growth and productivity, and to do so, they shuttle among various thermal micro-environments. Thus, the spatial distribution of temperatures in the habitat is important. Habitats dominated by either high or low extremes of an organism’s preference are energetically costly and dangerous (less optimal), especially to gravid females. This study examines thermal preference of a near-threatened species that also inhabits increasingly rare habitats. …

Genotyping Validates The Efficacy Of Photographic Identification In A Capture-Mark-Recapture Study Based On The Head Scale Patterns Of The Prairie Lizard (Sceloporus Consobrinus), Sarah A. Tomke, Chris J. Kellner

Forestry and Natural Resources Graduate Research

Population studies often incorporate capture‐mark‐recapture (CMR) techniques to gather information on long‐term biological and demographic characteristics. A fundamental requirement for CMR studies is that an individual must be uniquely and permanently marked to ensure reliable reidentification throughout its lifespan. Photographic identification involving automated photographic identification software has become a popular and efficient noninvasive method for identifying individuals based on natural markings. However, few studies have (a) robustly assessed the performance of automated programs by using a double‐marking system or (b) determined their efficacy for long‐term studies by incorporating multi‐year data. Here, we evaluated the performance of the program Interactive Individual …

Ticks On Lizards: Parasite-Host Interactions Of The Southern Alligator Lizard (Elgaria Multicarinata) In Washington State, Emma Houghton

All Undergraduate Projects

I investigated interactions between ectoparasites (ticks) and their host, the southern alligator lizard (Elgaria multicarinata). Alligator lizards are capable of complement-mediated killing of the Lyme disease spirochete carried by ticks and may potentially reduce Lyme disease prevalence by cleansing pathogenic organisms from ticks. Despite this, little is known about host-parasite dynamics in alligator lizards. My goals were to 1) assess patterns of tick presence (i.e. parasite load) on alligator lizards and 2) investigate potential negative effects of ticks on alligator lizards. I sampled lizards during the summer of 2019 near Catherine Creek, along the Columbia River Gorge in southern Washington. …

Ticks On Lizards: Parasite-Host Interactions Of The Southern Alligator Lizard (Elgaria Multicarinata) In Washington State, Emma Houghton

Undergraduate Honors Theses

I investigated interactions between ectoparasites (ticks) and their host, the southern alligator lizard (Elgaria multicarinata). Alligator lizards are capable of complement-mediated killing of the Lyme disease spirochete carried by ticks and may potentially reduce Lyme disease prevalence by cleansing pathogenic organisms from ticks. Despite this, little is known about host-parasite dynamics in alligator lizards. My goals were to 1) assess patterns of tick presence (i.e. parasite load) on alligator lizards and 2) investigate potential negative effects of ticks on alligator lizards. I sampled lizards during the summer of 2019 near Catherine Creek, along the Columbia River Gorge in southern Washington. …

Investment Of Both Essential Fatty And Amino Acids To Immunity Varies Depending On Reproductive Stage., Taylor V. Pettit, R. John Pettit, Andrew M. Durso, Susannah S. French

Ecology Center Publications

Trade‐offs among the key life‐history traits of reproduction and immunity have been widely documented. However, the currency in use is not well‐understood. We investigated how reproducing female side‐blotched lizards, Uta stansburiana, allocate lipids versus proteins when given an immune challenge. We tested whether lizards would invest more in reproduction or immunity depending on reproductive stage. Females were given stable isotopes (¹⁵N‐leucine and ¹³C‐1‐palmitic acid), maintained on a regular diet and given either a cutaneous biopsy or a sham biopsy (control). Stable isotopes were monitored and analyzed in feces and uric acid, skin biopsies, eggs, and toe …

Infestation Intensities, Attachment Patterns, And The Effect On Host Contest Behavior Of The Tick Ixodes Pacificus On The Lizard Sceloporus Occidentalis, Dylan M. Lanser

Master's Theses

Parasites often have profound effects on the survival and evolution of their hosts, and hence on the structure and health of entire ecosystems. Yet basic questions, such as the degree of virulence of a given parasite on its host, and factors influencing which hosts in a population are at the greatest risk of infection, are vexingly difficult to resolve. The western blacklegged tick-western fence lizard (Ixodes pacificus-Sceloporus occidentalis) system is important, primarily because I. pacificus, a vector of the Lyme disease spirochete Borrelia burgdorferi, is dependent on S. occidentalis for blood meals in its subadult stages, …

Cold-Climate Adaptation In The Five-Lined Skink: A Common-Environment Experiment, Madeline Michels-Boyce

All Graduate Theses, Dissertations, and Other Capstone Projects

Ectotherms in cold climates have unique obstacles, especially in winter. Reptiles at higher latitudes or elevations have differing strategies to survive harsher winters, but these differences (e.g. lowered metabolism and lower critical minimum temperatures) may be adaptations or the result of phenotypic plasticity that depends on environmental stimuli or an interactive effect of both. We collected five-lined skinks (Plestiodon fasciatus) from Texas and Minnesota to test for latitudinal differences in winter preparation in a common-environment experiment. We manipulated photoperiod and temperature to be either constant or decreasing, resulting in a 2x2 experiment. We asked three main questions: 1) Is there …

Cuban Treefrogs, Osteopilus Septentrionalis (Duméril & Bibron 1841) (Anura: Hylidae), And Other Nonindigenous Herpetofauna Interdicted In Grenada, Lesser Antilles., Louis A. Somma, Paul R. Graham

Papers in Herpetology

The number of introduced nonindigenous species of amphibians and reptiles within the greater Caribbean, including Grenada, is escalating and has become an ever-increasing critical conservation concern (Daudin and de Silva 2011; Powell et al. 2011; Powell and Henderson 2012). The amount of development, tourism, and consequent import commerce is increasing, requiring careful regulation of the pet trade and fauna introduced for biological control as well as diligence in cargo inspection. Herein we document the first records of nonindigenous Cuban Treefrogs, Osteopilus septentrionalis (Duméril and Bibron 1841), interdicted from cargo, along with recent interceptions of two species of nonindigenous lizards already …

Phylogeny And Systematics Of Panaspis And Afroablepharus Skinks (Squamata: Scincidae) In The Savannas Of Sub-Saharan Africa, Maria Fernanda Medina

Open Access Theses & Dissertations

African snake-eyed skinks are relatively small lizards of the genera Panaspis and Afroablepharus. The allocation of these genera was frequently rearranged in the 20th century based on morphology, ecology and biogeography. Members of these genera occur primarily in savanna habitats throughout sub-Saharan Africa and include species that have highly conserved morphology, which poses a challenge for taxonomic studies. We sequenced two mitochondrial (16S and cyt b) and two nuclear genes (PDC and RAG1) from 91 Panaspis and Afroablepharus samples from various localities in eastern, central and southern Africa. Concatenated gene-tree and divergence dating analyses were conducted to infer phylogenies and …

Prevalence And Transmission Potential Of Borrelia Burgdorferi In Three Species Of Wildcaught Plestiodon Spp. Skinks Of The Southeastern United States, Teresa Dianne Moody

Masters Theses

In the southeastern United States, blue-tailed skinks (Plestiodon spp.) are important hosts for Ixodes scapularis ticks, the principal vector of Lyme disease (LD) in this region. Skinks and other southeastern lizards are not thought to be reservoir competent for Borrelia burgdorferi sensu stricto (Bbss), the etiological agent of LD in the United States. . Lizard-feeding by southeastern I. scapularis may tend to suppress sylvatic cycles of B. burgdorferi, and thus may be an important reason why LD case rates in the Southeast are much lower than in the Northeast and upper Midwest. Nevertheless, some skinks …

Comparison Of Ectoparasitic Mite Loads Between Gonochoristic (Aspidoscelis Marmorata) And Parthenogenic (A. Tesselata) Syntopic Whiptail Lizards (Teiidae) From The Northern Chihuahuan Desert Of Trans-Pecos, Texas, William Dawson Lukefahr

Open Access Theses & Dissertations

The objective of this study was to compare the ectoparasitic loads between two syntopic whiptail lizard species (Teiidae) that differ in their reproductive modes; Aspidoscelis marmorata (bisexual) and A. tesselata (unisexual). The study site was located on Indio Mountains Research Station (IMRS) in a Chihuahuan Desert Scrub landscape in Hudspeth County, Texas. Previous studies conducted at IMRS showed the two species having similar diets, morphology, and reproductive characteristics, but fluctuated in nematode loads. No comparative study of ecotoparasitic mites (Eutrombicula alfreddugesi) between the two species has ever been done.

Aspidoscelis marmorata (n = 141) and A. tesselata (n = 144) …

Geographic Variation In The Lower Temperature Tolerance In The Invasive Brown Anole, Anolis Sagrei And The Native Green Anole, Anolis Carolinensis (Sauria: Polychrotidae), Laura Carolina Maria Rubio

Masters Theses

Invasive species are considered to be the second greatest threat to native biodiversity and several factors have been identified as contributing to the success of introduced species, including their initial genetic variation and the ability of populations to adapt to a new environment. Temperature has a significant impact on reptilian ecology and distribution since they ordinarily rely on external heat sources for the maintenance of body temperatures suitable for normal activity. Body temperature affects performance in these organisms given its importance for all aspects of behavior, locomotion, courtship and rates of feeding and growth. Critical thermal tolerances can, therefore, give …

The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The San Luis Valley is a large valley formation in Colorado surrounded on either side by mountain ranges exceeding 4,267 m. Within the Valley, two of the 14 amphibian and reptile species are dwarfed: the short-horned lizard (Phrynosoma hernandesi) and the Great Plains toad (Anaxyrus cognatus). Since its initial reporting in 1968 and confirmation in 1981, no research further investigating this dwarfism has been conducted. I collected morphological measurements to determine the extent and patterns of dwarfism of both species. I then investigated the genetics of both species using mitochondrial DNA to determine whether they are …

Estimates Of Toad Headed Agama Density In Three Steppe Habitats Of Mongolia, James Murdoch, Buyandelger Suuri, Richard P. Reading

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The toad headed agama (Phrynocephalus versicolor) ranges across the arid steppe regions of southern and western Mongolia and represents one of the most common reptiles in the country. However, few details of the species’ population characteristics exist, which may be important for evaluating population trends and assessing its conservation status. We estimated toad headed agama density in Ikh Nart Nature Reserve, Mongolia based on surveys conducted in the summers (June-September) of 2005, 2006, 2008, and 2009. We conducted surveys in three steppe habitats including tall grassland (n = 7), shrub-steppe (n = 7), and semi-shrub steppe …

The Effect Of Female Ornamentation On Aggressive Male-Male Interactions In The Striped Plateau Lizard (Sceloporus Virgatus), Matt E. Dubin

Summer Research

Theoretical and empirical studies have shown that the intensity of male-male competition is greatly influenced by the quality of the contested resource. To date few studies have focused on whether the quality of a contested female will have the same effect. Within a number of species, the quality of the female may be signaled with sexually selected female ornamentation. In the striped plateau lizard (Sceloporus virgatus), females develop ornamental orange throat patches before ovulation, and previous research has shown that females with larger ornaments are of higher phenotypic quality and also produce offspring with higher phenotypic quality, while …

Do Worm Lizards Occur In Nebraska?, Louis A. Somma

Papers in Herpetology

Amphisbaenids, or worm lizards, are a small enigmatic suborder of reptiles (containing 4 families; ca. 140 species) within the order Squamata, which include~ the more speciose lizards and snakes (Gans 1986). The name amphisbaenia is derived from the mythical Amphisbaena (Topsell 1608; Aldrovandi 1640), a two-headed beast (one head at each end), whose fantastical description may have been based, in part, upon actual observations of living worm lizards (Druce 1910). While most are limbless and worm-like in appearance, members of the family Bipedidae (containing the single genus Bipes) have two forelimbs located close to the head. This trait, and …

Notes On Maternal Behavior And Post-Brooding Aggression In The Prairie Skink, Eumeces Septentrionalis, Louis A. Somma

Papers in Herpetology

Observations of three female prairie skinks (E. septentrionalis) obtained in Omaha, NE, in 1983, including nest building, oviposition, incubation, defensive behavior, grooming of hatchlings, neonatal care, and post-brooding aggression.