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Ecology and Evolutionary Biology

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Tick-, Mosquito-, And Rodent-Bourne Parasite Sampling Designs For The National Ecological Observatory Network, Yuri Springer, David Hoekman, Pieter T.J. Johnson, Paul A. Duffy, Rebecca A. Hufft, Holly D. Gaff Jan 2016

Tick-, Mosquito-, And Rodent-Bourne Parasite Sampling Designs For The National Ecological Observatory Network, Yuri Springer, David Hoekman, Pieter T.J. Johnson, Paul A. Duffy, Rebecca A. Hufft, Holly D. Gaff

Biological Sciences Faculty Publications

Parasites and pathogens are increasingly recognized as significant drivers of ecological and evolutionary change in natural ecosystems. Concurrently, transmission of infectious agents among human, livestock, and wildlife populations represents a growing threat to veterinary and human health. In light of these trends and the scarcity of long-term time series data on infection rates among vectors and reservoirs, the National Ecological Observatory Network (NEON) will collect measurements and samples of a suite of tick-, mosquito-, and rodent-borne parasites through a continental-scale surveillance program. Here, we describe the sampling designs for these efforts, highlighting sampling priorities, field and analytical methods, and the …


The Small Mammals Of Southeastern Virginia As Revealed By Pitfall Trapping, Robert K. Rose Jan 2016

The Small Mammals Of Southeastern Virginia As Revealed By Pitfall Trapping, Robert K. Rose

Biological Sciences Faculty Publications

Pitfall trapping is a poor method to catch small mammals but the only way to catch and study the Southeastern Shrew (Sorex longirostris), the primary mammal of interest in the field studies reported here. While learning much about its distribution and abundance, still more was learned about the other small mammals present in forests and fields of eastern Virginia. A total of 15 species was captured at 19 locations during the 1990-2013 period, including five shrews, two moles, and eight rodents, representing all but one of the common small mammals in eastern Virginia.


Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky Jan 2016

Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky

Biological Sciences Faculty Publications

During a 17-yr telemetry study, we examined the diet and ambush behavior of a population of Crotalus horridus in southeastern Virginia. Forty dietary items were identified from 37 fecal samples. We documented 722 instances of snakes in an ambush posture, 61 of which were in a vertical-tree posture, as if hunting arboreal prey at the base of a tree. The most common prey items were Eastern Gray Squirrels (Sciurus carolinensis), which accounted for 45 of all dietary items and represented an estimated 78 of total biomass consumed by C. horridus. Prey was not consumed in proportion to availability, …


Genome Wide Epigenetic Analyses Of Araptus Attenuatus, A Bark Beetle, Chitra Seshadri Jan 2016

Genome Wide Epigenetic Analyses Of Araptus Attenuatus, A Bark Beetle, Chitra Seshadri

Theses and Dissertations

Phylogeographic studies have relied on surveying neutral genetic variation in natural populations as a way of gaining better insights into the evolutionary processes shaping present day population demography. Recent emphasis on understanding putative adaptive variation have brought to light the role of epigenetic variation in influencing phenotypes and the mechanisms underlying local adaptation. While much is known about how methylation acts at specific loci to influence known phenotypes, there is little information on the spatial genetic structure of genome-wide patterns of methylation and the extent to which it can extend our understanding of both neutral and putatively adaptive processes. This …


Seasonal Variation Of Fish And Macroinvertebrate Biomass Spectra In Southern West Virginia Streams, Andrew J. Kirk Jan 2016

Seasonal Variation Of Fish And Macroinvertebrate Biomass Spectra In Southern West Virginia Streams, Andrew J. Kirk

Theses and Dissertations

The biomass size spectrum - the power-law scaling relationship between average individual size and total biomass - has often been studied in lake and marine ecosystems, but rarely in lotic systems. The objective of this study was to test for characteristic biomass spectra in small temperate streams. Seasonal fish and macroinvertebrate data, including population abundance and biomass estimates, were collected in three wadeable, southern West Virginia streams from October 2013 to May 2015. Fish abundances were estimated with 3-pass electrofishing (depletion) surveys and individuals were weighed in the field. Macroinvertebrates were collected with a Hess sampler and returned to the …


Upper Thermal Limits Differ Among Component Species In A Host-Parasitoid-Hyperparasitoid System, Kanchan A. Joshi Jan 2016

Upper Thermal Limits Differ Among Component Species In A Host-Parasitoid-Hyperparasitoid System, Kanchan A. Joshi

Theses and Dissertations

Among the predicted impacts associated with global climate change, warming is of special interest because the rates of physiological processes are temperature-dependent. Insects and other ectotherms are likely to be affected due to their limited ability to control body temperature. In this study, I measured the tolerance to extreme high temperatures, i.e., critical thermal maximum (CTmax), of component species in a tri-trophic system, including an herbivore (Manduca sexta), a primary larval parasitoid (Cotesia congregata) and a hyperparasitoid (genus Silochalcis). For wild insects, the parasitoid had the lowest CTmax, the hyperparasitoid had …


From Seed To Sky: Impacts Of Explosive Compounds On Vegetation Across Spatial And Developmental Scales, Stephen M. Via Jan 2016

From Seed To Sky: Impacts Of Explosive Compounds On Vegetation Across Spatial And Developmental Scales, Stephen M. Via

Theses and Dissertations

Explosive compounds are broadly distributed across the globe as a result of nearly two centuries of munitions use in warfare and military activities. Two explosive compounds have seen disproportionate use; RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and TNT (2-methyl- 1,3,5-trinitrobenzene), being the most commonly found explosives in the environment. The effects of explosives on biota have been studied in great detail; however, there is a general lack of understanding with regard to broader ecological impacts of these contaminants. My dissertation objective was to follow the impacts of explosive compounds on vegetation across scales. Impacts on vegetation at the species scale alter community composition via …


Differential Response Of Barrier Island Dune Grasses To Species Interactions And Burial, April Harris Jan 2016

Differential Response Of Barrier Island Dune Grasses To Species Interactions And Burial, April Harris

Theses and Dissertations

Dune grasses are integral to biogeomorphic feedbacks that create and alter foredunes and barrier island stability. In a glasshouse study, Ammophila breviligulata Fern. and Uniola paniculata L. were planted together and subjected to sand burial to quantify morphological and physiological response. Ammophila breviligulata physiological and morphological performance declined when planted with U. paniculata but U. paniculata was not affected when planted with A. breviligulata. Burial had a positive effect on A. breviligulata and U. paniculata as indicated by electron transport rate and total biomass at the end of the experiment. Due to their different growth strategies, A. breviligulata and …


Structure And Function Of Male Bottlenose Dolphin Alliances In Northeast Florida, Kristin A. Karle Jan 2016

Structure And Function Of Male Bottlenose Dolphin Alliances In Northeast Florida, Kristin A. Karle

UNF Graduate Theses and Dissertations

Bottlenose dolphins exhibit fission-fusion social systems in which group size and composition change fluidly throughout the day. Societies are typically sexually segregated, and the quality and patterning of individual relationships in this social species shape the social structure of a population. Female dolphins usually have a large network of associates with whom they form recurring moderate bonds, while male associations are highly variable due to their mating strategies. Males employ one of two strategies; males may be solitary, and encounter and herd females individually, while others may form strong bonds with one to two other males and cooperatively herd individual …


Biogeographical Patterns In The Hard-Tick Genus Amblyomma Koch 1844 (Acari: Ixodidae), Matthew H. Seabolt Jan 2016

Biogeographical Patterns In The Hard-Tick Genus Amblyomma Koch 1844 (Acari: Ixodidae), Matthew H. Seabolt

College of Graduate Studies: Theses & Dissertations

Amblyomma Koch is a genus of hard-ticks with approximately 130 species. Its geographical range is typical for organisms with a Gondwanan origin. A majority of these species are endemic to the Neo- and Afrotropical regions, with the remaining taxa dispersed throughout Southeast Asia, Australia and the Pacific islands. Based on this distribution, we hypothesize that the genus dispersal patterns will mirror the fragmentation and continental drift of the Gondwanan supercontinent. Maximum parsimony, maximum likelihood, Bayesian inference and node-dating analyses of nuclear 18S rDNA gene sequences reveal a more recent origin and radiation patterns within the genus and suggest that Amblyomma …


Assemblage Structure, Production, And Food Web Dynamics Of Macroinvertebrates In Tropical Island Headwater Streams, Keysa G. Rosas-Rodriguez Jan 2016

Assemblage Structure, Production, And Food Web Dynamics Of Macroinvertebrates In Tropical Island Headwater Streams, Keysa G. Rosas-Rodriguez

College of Graduate Studies: Theses & Dissertations

Variation in long-term temperature and precipitation patterns will likely influence the decomposition and export of benthic organic matter and influence aquatic macroinvertebrate consumer communities. Tropical systems are relatively understudied; therefore basal information is urgently needed. As part of an ongoing long-term study, we monitored macroinvertebrates in two shrimp-dominated and fishless headwater streams within the Luquillo Experimental Forest in Puerto Rico from 2009-2010. We combined growth rates with yearly biomass data to calculate secondary production and examined gut contents to develop quantitative food webs. Macroinvertebrate assemblages were dominated by a few insect taxa, with similar biotic composition across streams and habitats, …


Transcriptional Regulation Of Specialized Metabolites In Arabidopsis Thaliana And Catharanthus Roseus, Craig M. Schluttenhofer Jan 2016

Transcriptional Regulation Of Specialized Metabolites In Arabidopsis Thaliana And Catharanthus Roseus, Craig M. Schluttenhofer

Theses and Dissertations--Plant and Soil Sciences

For millennia humans have utilized plant specialized metabolites for health benefits, fragrances, poisons, spices, and medicine. Valued metabolites are often produced in small quantities and may command high prices. Understanding when and how the plant synthesizes these compounds is important for improving their production. Phytohormone signaling cascades, such as jasmonate (JA) activate or repress transcription factors (TF) controlling expression of metabolite biosynthetic genes. TFs regulating specialized metabolite biosynthetic genes can be manipulated to engineer plants with increased metabolite production.

WRKY transcription factor are known components of both JA signaling cascades and regulation of specialized metabolism. The presence of WRKY binding …


A Tale Of Two Palmettos: The Foundation Of Ecosystems, Warren G. Abrahamson Ii Jan 2016

A Tale Of Two Palmettos: The Foundation Of Ecosystems, Warren G. Abrahamson Ii

Faculty Journal Articles

Fruits of saw palmetto (Serenoa repens) provide crucial, high-quality resources to wildlife while providing a matrix for many southeastern US ecosystems. As a foundation species, saw palmetto plays a major role in structuring fire-maintained plant communities. Often living on nutrient-poor soil conditions, the thick leaves of saw palmetto are long lived, up to 2.8 years in shaded sand pine scrub.


Evidence Of Rock Kangaroo Seed Dispersal Via Faecal Seed Storage In A Tropical Monsoon Community, Chris Martine, Ally Boni, Elizabeth Capaldi, Gemma Lionheart, Ingrid E. Jordon-Thaden Jan 2016

Evidence Of Rock Kangaroo Seed Dispersal Via Faecal Seed Storage In A Tropical Monsoon Community, Chris Martine, Ally Boni, Elizabeth Capaldi, Gemma Lionheart, Ingrid E. Jordon-Thaden

Faculty Journal Articles

While some of the plant species of the ‘Sandstone Country’ along the escarpment of western Arnhem Land produce fleshy fruits and appear to rely on biotic methods of seed dispersal, little is known about the methods by which this is achieved – and few potential dispersers co-occur in the sandstone outcrop communities. For the present study, scat collections were made on outcrops in the northeastern area of Kakadu National Park with the hope of uncovering relationships between local frugivores and fruit-producers, and providing evidence for seasonal storage of mammal-dispersed seeds in scat prior to germination. The goals of the present …


No Cortex, No Cry, Vladimir Dinets Jan 2016

No Cortex, No Cry, Vladimir Dinets

Animal Sentience

In his target article, Key (2016) argues that since fish don’t have a frontal cortex (part of the brain known to be important for feeling of pain in humans and rodents), they cannot feel pain or other noxious stimuli. I comment on the logic used in this extrapolation and other arguments presented in the paper.


Mediating Claims Through Critical Anthropomorphism, Gordon Burghardt Jan 2016

Mediating Claims Through Critical Anthropomorphism, Gordon Burghardt

Animal Sentience

Key’s (2016) discussion of his claim that fish do not feel pain ignores the history of attempts to study the attribution of mental states to other species. Although willing to accept that mammals feel pain, Key claims that fish lack the mammalian neural mechanisms underlying pain and are unconscious of their experiences. Consequently, we do not need to be overly concerned about fishing practices that would otherwise be viewed as painful. Key uses a flawed anthropomorphic lens. All attributions of mental events to organisms other than oneself involve inferences derived from anthropomorphic processes through which we process physiological and behavioral …


Pain And Other Feelings In Humans And Animals, Antonio Damasio, Hanna Damasio Jan 2016

Pain And Other Feelings In Humans And Animals, Antonio Damasio, Hanna Damasio

Animal Sentience

Evidence from neuroanatomy, neurophysiology, and neuropsychology suggests that the experience of feelings in humans does not depend exclusively on structures of the cerebral cortex. It does not seem warranted to deny the possibility of feeling in animals on the grounds that their cerebral cortices are not comparable to those of humans.


Where Is Pain In The Brain?, Marshall Devor Jan 2016

Where Is Pain In The Brain?, Marshall Devor

Animal Sentience

Key argues that fish cannot experience pain based on (1) brain imaging in humans, (2) consequences of lesions and (3) direct brain stimulation. Imaging indeed shows that pain-relevant signals reach the cortex, but not that they underlie the subjective experience of pain. Lesions and stimulation data are more to the point, but Key paints an idiosyncratic and misleading picture of their effects. S1 and S2 ablation does not eliminate evoked or spontaneous pain, although there may be up- or down-modulation. Likewise, stimulation of pain-associated cortical areas rarely induces pain, and pain almost never occurs at the onset of epileptic seizures. …


Fish Pain: Would It Change Current Best Practice In The Real World?, B. K. Diggles Jan 2016

Fish Pain: Would It Change Current Best Practice In The Real World?, B. K. Diggles

Animal Sentience

Much of the “fish pain debate” relates to how high the bar for pain should be set. The close phylogenetic affinities of teleosts with cartilaginous fishes which appear to lack nociceptors suggests caution should be applied by those who seek to lower the bar, especially given the equivocal and conflicting nature of the experimental data currently available for teleosts. Nevertheless, even if we assume fish “feel pain,” it is difficult to see how current best practice in aquaculture would change. This is because of the need to avoid stress at all stages of the rearing process to optimize health, growth …


Falsifying The Null Hypothesis That “Fish Do Not Feel Pain", Brian Key Jan 2016

Falsifying The Null Hypothesis That “Fish Do Not Feel Pain", Brian Key

Animal Sentience

The reader of Animal Sentience may surmise that because the weight of the commentaries on my target article, “Why fish do not feel pain,” is leaning towards not supporting my argument, it follows that the premise "fish do not feel pain" is incorrect. However, science does not prevail by popular opinion. History is plagued with numerous (and often widely accepted) examples of biological phenomena being explained by mysterious forces. In the absence of a mechanistic understanding, the many different guises of vitalism (the principle that life involves a vital energy) are often invoked to explain the unknown. Spurious …


The Microbiome In Light Of Host Evolution, Alexander M. Waldrop Jr. Jan 2016

The Microbiome In Light Of Host Evolution, Alexander M. Waldrop Jr.

Theses and Dissertations

Recent advances in sequencing technologies have provided an unprecedented window in the unseen biological world. Accompanying this revolution is a growing appreciation for the ubiquity and diversity of beneficial interactions between animals and the microbes they carry. Given the symbiotic roles of microbes in host nutrition, immunity, behavior, development, and nearly every other facet of host biology, it is becoming increasingly clear that any understanding of hosts and their evolution would be incomplete without also considering the microbial dimension. Yet despite the growing body of evidence that many of these partnerships are rooted deep in evolutionary time, the majority of …


Demographics And Parasites Of Spotted Bass In The Wabash River, Evan C. Boone Jan 2016

Demographics And Parasites Of Spotted Bass In The Wabash River, Evan C. Boone

Masters Theses

Spotted Bass Micropterus punctulatus Rafinesque are a popular sport fish primarily found in the streams and reservoirs of the south. The Wabash River, a large tributary of the Ohio River, contains a naturally reproducing population on the northern boundary of their range. Currently, the lower Wabash River is monitored using two different sampling designs, the Long Term Electrofishing Program monitors community assemblages using stratified random sampling whereas the Illinois Department of Natural Resources uses a fixed sampling design. Due to the wide distribution but low abundance of Spotted Bass throughout this drainage, captures from each design were compared to assess …


Diel And Seasonal Patterns Of Channel Catfish Movement And Habitat Use In The Lower Wabash River, Hanna Gibbs Kruckman Jan 2016

Diel And Seasonal Patterns Of Channel Catfish Movement And Habitat Use In The Lower Wabash River, Hanna Gibbs Kruckman

Masters Theses

Channel catfish Ictalurus punctatus are commonly found throughout the Mississippi River basin and support commercial and recreational fisheries in many large river systems. Understanding population demographics as well as movement patterns and habitat usage can provide a more holistic approach to species management and conservation. Within a 16-km stretch of the lower Wabash River, 27 channel catfish were implanted with acoustic transmitters to monitor fine scale movement and habitat use from September 2014 through April 2016. Channel catfish were located using active tracking during two types of tracking events. Site tracking occurred only during daylight hours and diel tracking monitored …


Stopover Ecology Of Neotropical Migratory Songbirds In The Northern Yucatan Peninsula, Mexico, Lauren E. Solomon Jan 2016

Stopover Ecology Of Neotropical Migratory Songbirds In The Northern Yucatan Peninsula, Mexico, Lauren E. Solomon

Masters Theses

Chapter I. Full-service hotels, convenience stores or fire escapes? Evaluating function of stopover sites for Neotropical migrants in the northern Yucatan Peninsula

Nearctic-Neotropical migratory songbirds incur the highest mortality rates during their annual migrations. Migratory songbirds use a network of stopover sites to rest, refuel, or seek refuge during times of poor weather conditions; and the time and energy expended at these sites exceeds that of migratory flight. In order to conserve stopover sites with the highest value to Neotropical migrants, a conceptual framework was developed to classify stop over sites into three functional categories based on their function for …


Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff Jan 2016

Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff

Masters Theses

Bats have an astonishing diversity and provide vital ecosystem services in an array of different niches. In North America, most species of bats are insectivores and tend to be frequently overlooked for their important ecosystem role providing insect control. As bat populations have declined in recent years, farmers, land managers, conservationists, and bat enthusiasts have wondered what we can do to protect our local bat populations. As a first step, we need to develop methods that more effectively survey for rare species of bats. By performing inefficient surveys, we are doing a disservice to our funding agencies providing misinformation that …


Responses To Familiar And Unfamiliar Humans By Belugas (Delphinapterus Leucas), Bottlenose Dolphins (Tursiops Truncatus), & Pacific White-Sided Dolphins (Lagenorhynchus Obliquidens): A Replication And Extension, Heather M. Hill, Deirdre Yeater, Sarah Gallup, Sara Guarino, Steve Lacy, Tricia Dees, Stan A. Kuczaj Ii Jan 2016

Responses To Familiar And Unfamiliar Humans By Belugas (Delphinapterus Leucas), Bottlenose Dolphins (Tursiops Truncatus), & Pacific White-Sided Dolphins (Lagenorhynchus Obliquidens): A Replication And Extension, Heather M. Hill, Deirdre Yeater, Sarah Gallup, Sara Guarino, Steve Lacy, Tricia Dees, Stan A. Kuczaj Ii

Psychology Faculty Publications

Previous research has documented that cetaceans can discriminate between humans, but the process used to categorize humans still remains unclear. The goal of the present study was to replicate and extend previous work on the discrimination between familiar and unfamiliar humans by three species of cetaceans. The current study manipulated the familiarity and activity level of humans presented to 12 belugas (Delphinapterus leucas) housed between two facilities, five bottlenose dolphins (Tursiops truncatus), and six Pacific white-sided dolphins (Lagenorhynchus obliquidens) during free-swim conditions. Two measures of discrimination were coded from video recordings of each trial: …


An Examination Of Plant Community Composition In Six Carolina Bays On The Coastal Plain Of South Carolina, Katherine L. Altman-Goff Jan 2016

An Examination Of Plant Community Composition In Six Carolina Bays On The Coastal Plain Of South Carolina, Katherine L. Altman-Goff

Electronic Theses and Dissertations

Historically high rates of human impact and recent Supreme Court cases, which have affected the regulation of geographically isolated wetlands in the United States, suggest that Carolina bays may be at high risk of human impacts in the future. Conservation efforts should be established based on applied ecological data and, if regulations by state and federal agencies are unable to conserve Carolina bay wetlands, it may be important to prioritize individual bays for preservation on protected lands. I examined plant community composition, diversity, richness, and rarity and soil parameters in six Carolina bays across South Carolina, using a replicated ecological …


Constructing A River, Building A Border: An Environmental History Of Irrigation, Water Law, State Formation, And The Rio Grande Rectification Project In The El Paso/Juárez Valley, Joanne Kropp Jan 2016

Constructing A River, Building A Border: An Environmental History Of Irrigation, Water Law, State Formation, And The Rio Grande Rectification Project In The El Paso/Juárez Valley, Joanne Kropp

Open Access Theses & Dissertations

The Rio Grande in the El Paso, Texas, U.S./Juárez, Chihuahua, Mexico, Valley has a long history of human use from prehistoric to modern times. Formal irrigation began in the 1600s, mainly for viticulture, changing to cotton and pecans in the 1900s. The Rio Grande was subject to bed shifting and flooding that, after 1848, affected the location of the international boundary. During the Great Depression the U.S. and Mexican governments sponsored conservation projects to provide jobs and increase agricultural production. The 1933 “Convention - Rectification of the Rio Grande” was the culmination of interstate and bi-national agreements to divide Rio …


Comparing Process-Based And Constraint-Based Approaches For Modeling Macroecological Patterns, Xiao Xiao Jan 2016

Comparing Process-Based And Constraint-Based Approaches For Modeling Macroecological Patterns, Xiao Xiao

Biology Faculty Publications

Ecological patterns arise from the interplay of many different processes, and yet the emergence of consistent phenomena across a diverse range of ecological systems suggests that many patterns may in part be determined by statistical or numerical constraints. Differentiating the extent to which patterns in a given system are determined statistically, and where it requires explicit ecological processes, has been difficult. We tackled this challenge by directly comparing models from a constraint-based theory, the Maximum Entropy Theory of Ecology (METE) and models from a process-based theory, the size-structured neutral theory (SSNT). Models from both theories were capable of characterizing the …


Clusters Of Alpha Satellite On Human Chromosome 21 Are Dispersed Far Onto The Short Arm And Lack Ancient Layers, William Ziccardi, Chongjian Zhao, Valery Shepelev, Lev Uralsky, Ivan Alexandrov, Tatyana Andreeva, Evgeny Rogaev, Christopher Bun, Emily Miller, Catherine Putonti, Jeffrey Doering Jan 2016

Clusters Of Alpha Satellite On Human Chromosome 21 Are Dispersed Far Onto The Short Arm And Lack Ancient Layers, William Ziccardi, Chongjian Zhao, Valery Shepelev, Lev Uralsky, Ivan Alexandrov, Tatyana Andreeva, Evgeny Rogaev, Christopher Bun, Emily Miller, Catherine Putonti, Jeffrey Doering

Bioinformatics Faculty Publications

Human alpha satellite (AS) sequence domains that currently function as centromeres are typically flanked by layers of evolutionarily older AS that presumably represent the remnants of earlier primate centromeres. Studies on several human chromosomes reveal that these older AS arrays are arranged in an age gradient, with the oldest arrays farthest from the functional centromere and arrays progressively closer to the centromere being progressively younger. The organization of AS on human chromosome 21 (HC21) has not been well-characterized. We have used newly available HC21 sequence data and an HC21p YAC map to determine the size, organization, and location of the …