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Pigmentary color is used across nature for signaling, camouflage, and protection. Consequently, the menagerie of colors seen in avian feathers presents an intriguing puzzle for materials engineers, as the same building blocks, pigments and keratin, are used to produce radically different plumage. While the showier coloration mechanism of structural color has been investigated from a materials science perspective, the production of pigmentary color, which may be less constrained, has largely been neglected from a structural perspective. I used Scanning Electron Microscopy (SEM) to image the internal feather structure of twelve species of Southern Capuchino Seedeaters (genus Sporophila) over a range of species, colors, and body feather patches. This group of birds is of particular interest due to its low level of genetic differentiation, which shows divergence mainly in the melanogenesis pathway, and therefore represents an opportunity to study the evolution of the mechanisms of plumage coloration. Key findings include: (1) Fontana Masson stain can be used with backscattered electron SEM to image individual granules of melanin within feathers, (2) white feathers are produced by an absence of melanin, (3) either round or oblong melanosomes can contain primarily eumelanin and produce black or grey feathers while only round melanosomes containing a majority of pheomelanin produce cinnamon or rufous colors, (4) oblong melanosomes are associated with the crown patch, and (5) all oblong melanosomes were found in feathers with at least seven times more eumelanin than pheomelanin. This work contributes to our understanding of the link between plumage differences in the Southern Capuchino Seedeaters and specific genetic changes in the deposition of melanosomes and melanin pigments. Furthermore, it presents a new technique for in situ feather melanin visualization, opening the door for analysis of intra-feather melanin patterning and melanin placement within periodic structural color systems.

Birds are hosts to a variety of bacteria and fungi including some that are keratinolytic. These feather degrading bacteria, including Bacillus licheniformis, are capable of degrading β-keratin which is a major component of feathers. While there is little evidence to indicate that feather degrading bacteria are capable of degrading feathers on live birds, there is ample evidence to indicate that many bird species experience altered feather coloration. There is significant variation in the reported prevalence of B. licheniformis on birds with percentages ranging from 6.7% to 99%. This study sought to provide further support for an overall prevalence of B. licheniformis on Northern Saw-Whet Owls. 14 possible B. licheniformis colonies were isolated resulting in a prevalence of 85.7%.

The modern musician faces a new challenge: how can technology be used to enhance a performance? This thesis documents the development of a Bluetooth remote controller that will aid today’s performing musicians by interacting with a digital display (e.g., an iPad) to flip musical score pages remotely. At its core, while mimicking a Bluetooth pedal (the current industry standard), this device attaches to the musician’s hand. In its pilot stages, the device has been referred to “MBC” (Music Bluetooth Controller).

A key element in computer-graphics research is representing the world around us, and immense inspiration may be found in nature. Algorithms and procedural models may be developed that can describe the three-dimensional shape of objects and how they interact with light. This thesis focuses particularly on bird and other dinosaur feathers and their structure. More specifically, it addresses the problem of procedurally generating biologically driven geometry for modeling feathers in computer graphics. As opposed to previously published methods for generated feather geometry, data is derived from a myriad of real-world specimens of feathers and used in creating graphical models of feathers. Modeling feathers is of interest both for media production and also for various fields of research such as ornithology, paleontology, and material science. In order to create realistic, computer-graphics feathers, the anatomy of feathers is analyzed in detail with the aim of understanding their structure and variation in order to apply that understanding to modeling. Data concerning the shape of actual feathers was collected and analyzed to drive attribute parameters for modeling accurate synthetic feathers, during which methods for generating geometry informed by the data were investigated. Synthesized image results, capabilities, limitations, and extensions of the developed techniques are presented.

Melanins are a class of ubiquitous pigments that provide not only coloration to the organisms in which they produced, but also serve as a mechanism for thermoregulation, protection from ultraviolet radiation and cytotoxicity induced by free radicals, as well as numerous other beneficial roles. In most animals, melanins are housed in organelles called melanosomes. Melanosome morphology correlates with melanin-based coloration in birds and mammals, but melanosome diversity is limited in basal amniotes. Approximately 10 years ago, the study of melanosomes, melanin, and coloration was extended to the fossil record by the reinterpretation of microbodies preserved in fossil feathers initially interpreted as bacteria as remains of melanosomes. However, despite countless lines of evidence for this hypothesis that have been described since, some authors argue that the bacterial hypothesis is equally parsimonious.This dissertation will address some of the concerns of purveyors of the bacterial hypothesis and discuss the evolutionary history of melanosomes and melanins. We first tested the hypothesis that striped fossil feathers are the result of bacterial preservation through taphonomic experimentation. We found that modern keratinolytic bacteria preferentially colonize unpigmented stripes in modern feathers over melanized stripes, so it is unlikely that this hypothesis was supported in ancient ecosystems. We also found that bacteria and biofilms preserved in association with fossil integument are dissimilar to microbodies interpreted as fossil melanosomes. We began the second part of this dissertation by describing an enantiornithine bird that exhibits a mix of juvenile skeletal characteristics and sexual ornaments. Melanosomes preserved in its feathers are similar in morphology and arrangement to those in modern iridescent feathers, which are predominantly used to attract mates. We also described melanosomes associated with the fossilized skin of amphibians and lampreys, which do not exhibit diverse melanosome morphologies. Convergent shifts in melanosome diversity in mammals and pennaraptoran dinosaurs may have occurred due to changes in physiology between these two groups and their ancestors. Finally, we reviewed the functions of melanins in modern organisms and evidence for these functions in the fossil record. Based on their modern ubiquity, we hypothesized that melanin may have evolved early in the history of life.

This dissertation aims to contribute toward the understanding of water-entry and -exit behaviors in nature. Since water is nearly a thousand times denser than air, transitioning between the two mediums is often associated with significant changes in force. Three topics with implications in water-entry are discussed, along with a fourth topic on water-exit. For a plunge-diving seabird, the first two stages of water-entry (initial impact and air-cavity formation) create large stresses on the bird's neck. Linear stability analysis of a cone-beam system impacting water shows buckling and non-buckling behaviors on the beam, which is extended to the diving birds. The next topic is related to the third stage of water-entry (air-cavity pinch-off), in which the chest feathers come in contact with the water. Here, the elasticity of Northern Gannet contour feathers is calculated using the nonlinear bending equation. The third topic will explore the formation of ripples along air cavity walls and their resulting force after pinch-off. An acoustic model predicts the observed wavelengths of the ripples. The final topic will delve into the mechanics of how animals leap out of water. A scaling law that balances the power of thrust and drag will predict the height of the jump. Finally, a bio-inspired robot was built to help identify physical conditions required to jump out of water.

Due to their unique physicochemical and enhanced immunostimulatory properties, quantum dot (QD) nanoparticles have shown increasing promise in biomedical research applications including bioimaging, drug delivery, and as vaccine adjuvants. Toxicity, however, remains a concern for the use of QD in these applications and thus, there is an increased demand for effective in vitro and in vivo systems to measure the bioactivity of QD. In this study in vitro and in vivo chicken models were used to investigate the effects of QD on innate and adaptive immunity. Chicken macrophage cultures were treated in vitro with QD to measure macrophage activation and the effect of QD on cell viability. The chicken growing feather (GF) injection model was used as the cutaneous test-site to monitor leukocyte infiltration in response to intradermal injection of QD without and with conjugation to a protein antigen. Additionally, the humoral and cellular adaptive immune responses to protein antigen conjugated to QD were examined in chickens. In vitro results showed negligible macrophage activation in response to QD treatment; however, cell viability was negatively affected by QD in a dose-dependent manner. Leukocyte infiltration results of in vivo GF injections with QD revealed immunostimulatory activity of QD, independent of whether or not QD were conjugated to protein antigen. When used as a vaccine platform, immunization with QD conjugated with protein antigen generated a higher primary and secondary antibody response compared to antigen mixed with alum adjuvant. The adaptive cellular responses to protein antigen examined in GF of immunized chickens also support an important role of B cells in the local effector phases of the responses, while T cells appear to primarily help in B cell activation and differentiation, including antibody isotype switching from IgM to IgG. These results provide additional evidence that QD possess promising vaccine adjuvant properties while demonstrating the viability and utility of the minimally invasive chicken GF cutaneous test-site to study the immunostimulatory effects of nanoparticles initiated in vivo. Further investigation of nanoparticles using the chicken GF injection model should provide additional valuable knowledge of the relative risks and rewards of using QD in biological applications.

Structurally colored feathers render color through physical scattering of light rather than pigments. There is an expected, but heretofore unexplored, effect of adhesive choice and pressure on the color of these materials. Further, such feathers are generally considered to be more light-stable than their pigmented counterparts. In the current study, structurally colored blue kingfisher feathers are used to examine these effects in order to guide conservation treatments and preventive care. The Chinese tradition of diancui, literally "dotting [a surface] with [kingfisher-feather] blue", describes a technique of cloisonné style jewelry that utilizes blue, blue-green, and purple feathers instead of fused glass powder. The feathers are adhered to a substrate, usually metallic, though occasionally composed of thick layers of paper. This technique appears in Chinese culture from as early as the first century BCE, though surviving examples date most prevalently to the Qing dynasty (19th century) (Chambers et al. 1981, 32). The early featherwork items were not restricted to jewelry, but also appeared in the form of feather mosaics on clothing, bed coverings, and palanquins (Chambers et al. 1981, 32; Garrett 1994, 86). Such items are now ubiquitous in museum collections. Through a technical study of kingfisher feather jewelry from the Ruth Chandler Williamson Gallery at Scripps College in Claremont California, as well as accelerated light aging studies and pressure tests completed on mocked up samples of recently plucked kingfisher feathers at both the UCLA/Getty and the Getty Conservation Institute labs, I evaluate the effects of original and conservation/restoration adhesives and coatings, and effects of mechanical interactions, on the structural colors of the feathers. For the experimental part of the study, feather specimens from skins of Halcyon smyrnensis, the White-breasted Kingfisher, donated by the United States Fish and Wildlife Department, were plucked, trimmed, and adhered onto inert quartz glass plates and subjected to three methods of light aging, with color measurements occurring after aging with an integrating sphere. The accelerated light aging methods included museum conditions (free of ultraviolet radiation), window conditions (ultraviolet radiation present), and high intensity UVA conditions, with an additional control group kept in the dark. Adhesive systems tested were those documented as having been used originally or in the conservation of kingfisher featherwork, including: protein glues (gelatin and isinglass), funori, methylcellulose, and Paraloid B-72. Characterizing the adhesives used on the Scripps collection items provided supporting technical evidence. Taken together, the results of this study provide insights into kingfisher feather diancui technology, and the effect of adhesive systems and mechanical actions on the preservation of color within these structurally colored feathers. The color stability is strong, with little visible alteration in the color of unadhered feather samples from all aging chambers. However, feathers subjected to high intensity UVA radiation displayed the most significant shift in a* and b* values, becoming more colorless or grey. Adhesive choice does not result in a major difference in feather color, except Paraloid B-72, which results in darker, more saturated blue-greens. The yellow-green spots apparent on the kingfisher jewelry were not recreated on the mocked up samples and require further investigation. As the likely source for original adhesives, animal glue (or gelatin), isinglass, and funori are not recommended for conservation intervention. Methylcellulose, of the tested adhesives, may be the best choice for stabilizing comparative objects.

Abstract: Chicken feathers are an abundant by-product from poultry industry. Feathers are composed of around 90% keratin, a valuable protein bioresource that have great potential for non-food applications. Keratin is characterized by a high content of cysteine residues forming disulfide bonds. This feature makes keratin an interesting biopolymer for the fabrication of mechanically resistant materials, including thermoplastics and tissue engineered scaffolds. Therefore, the overall objectives of the thesis are 1) to fabricate and improve mechanical properties of chicken feather thermoplastics; 2) to study and characterize the self-assembly of feather keratin hydrogels and their physical and biological properties; 3) to compare hydrogel properties of hair, wool and feather keratins; and 4) to evaluate the feasibility of electrospinning of feather keratin for the fabrication of nanofibrous scaffolds. Chicken feathers were mixed with glycerol/propylene glycol plasticizers and thermally processed into plastic films. The tensile mechanical properties of films were evaluated. Incorporation of up to 2% graphite oxide nanoparticles resulted in enhanced tensile strength and Young modulus of plastic films, which were attributed to keratin intercalation into graphene oxide nanosheets and interaction between oxygen functionalities of graphite oxide with amino acid side groups of keratin, and plasticizers. Chicken feather keratin was also studied for developing scaffolds for potential application in tissue engineering. Keratin from chicken feathers was solubilized in a solution containing urea, thiourea, and sodium metabisulfite. Keratin hydrogels were spontaneously formed during controlled dialysis of extracted keratin solution. Keratin gelation and stability of gels was mainly controlled by the extent of disulfide bond re-formation. Gelation at neutral pH proceeded slowly towards the formation of transparent gels, whereas rapid gelation occurred at pHs of 3 and 9 due to isoelectric aggregation and increased rate of disulfide exchange reactions, respectively. Hydrogels had similar viscoelastic properties of adipose and dermal tissue. Increasing keratin concentration resulted in increased storage modulus of hydrogels; however, swelling capacity and porosity decreased with increased concentration. Hydrogel scaffolds supported the growth of human dermal fibroblasts (HDFa) over a period of 21 days. Cells infiltration was affected by the dense arrangement of keratin and lower porosity in hydrogels prepared at (10 and 12.5%), where the growth of cells was limited to the surface of scaffolds. Keratin from different sources was compared for their hydrogel properties. Keratin from hair, wool and feathers were characterized by their molecular weight, amino acid composition, and thermal and conformational properties. Hydrogels from feather keratin demonstrated substantially higher storage modulus (~10 times higher) than others. However, higher swelling capacity (>3000%) was determined in hair and wool over feather keratin (1500%) hydrogels. The smaller molecular weight and -sheet structure of feather keratin facilitated the self-assembly of rigid hydrogels. Whereas, higher molecular weight stretchable -helix keratins in hair and wool resulted in weaker hydrogels. Fibroblasts showed the highest proliferation rate on feather keratin hydrogel scaffolds, which was attributed to their superior viscoelastic properties. In the last part of the thesis, the potential of forming keratin nanofibers through electrospinning was evaluated. Electrospun keratin nanofiber were fabricated with non-toxic solvents and crosslinking reagents. Keratin was solubilized at room temperature in a 1 M NaOH solution. Poly(vinyl alcohol) (PVA)/citric acid aqueous solution was used as an aid for electrospinning. Solutions containing 10, 20, and 30% keratin/PVA mass ratio were successfully electrospun. The diameter of nanofibers decreased from 565 ± 154 nm in PVA to 274 ± 42nm in 20% keratin electrospun mats, which was attributed to a reduction in the viscosity of the solutions. Further decrease in viscosity with 30% keratin resulted in beads-on-fiber. The resultant nanofibrous mats were thermally cross-linked by esterification of PVA hydroxyl groups with carbonyl groups in citric acid. The incorporation of keratin in PVA nanofiber was confirmed by FTIR and XPS results. Proliferation of fibroblasts after 14 days was higher in scaffolds containing 20% keratin, which was attributed to the superior biological properties of keratin and higher surface area to volume ratio compared to 30% keratin. Feather keratin is a valuable bioresource for material applications. Feather plastics can be evaluated for applications including agricultural films. Keratin hydrogel and electrospun mat scaffolds support the proliferation of fibroblasts, making them potential materials for in vivo studies in skin tissue engineering. 

Biomimicry refers to the work of people who realize that the organic structures or survivingoutcomes of nature are not only seemingly beautiful but also durable and who apply them tohuman inventions by designing with the methods of nature. There are many projects around theworld utilizing biomimicry, even from before the term was commonly used. Furthermore,biomimicry is increasingly employed in architecture. In this thesis, I will examine the design ofan airport building through biomimicry. Because of a correlation between flights, airplanes,airports, and feathers, I have selected a feather for my biological inspiration. The structuralpattern of feathers allows them to sustain their shape and function in flight. Understanding theprinciple of this structure, which is based on interlocking systems of hooks (barbicels) with threedifferent hierarchies (rachis, barbs and barbules), allows a plausible formulation for a lightweightlong-span structure of an airport by designing a feather-like canopy unit. The site I have selectedfor this examination is Cincinnati/Northern Kentucky International Airport (CVG), which is indecline due to decreased demand. Hoping for a revitalization, the airport management plans tocombine Concourse A and Concourse B as one compact concourse in 2023 to reduce the waste,maintenance fees, and unnecessary spaces. Based on these needs from CVG, I propose a newconcourse by mimicking a feather’s structure to design an innovative new airport facility.

With our global population on the rise, there is a need not only for alternative sources of energy for both humans and animals, but also for alternative food sources to maintain food security. Microalgae from biofuel production and poultry feather waste are both rich in protein, and stand as promising candidates for supplementation into animal diets as protein-rich feed additives. In doing so, the corn and soybean meal that traditionally make up the majority of an agricultural animal's diet, may be re-allocated for human consumption. Additionally, developing new uses for a waste product of the biofuel industry (microalgae) and poultry industry (feathers) would help alleviate environmental pollution. We aimed to 1) determine the nutritional potential of supplementing microalgae biomass into the diets of weanling pigs, without negatively affecting their growth performance or health, and 2) improve the digestibility of poultry feathers in vivo through the use of cloned and expressed microbial enzymes in in vitro feather hydrolysis. Protein-rich microalgal biomass from biofuel production stands as a promising new animal feed source, and may serve as an alternative to corn and soybean meal (SBM) in animal diets. Our objective was to determine potential and limitation of a new diatom microalgal species Staurosira sp (full-fat microalgae) and its defatted algal biomass generated from biofuel production in replacing SBM and corn in diets for weanling pigs. Two experiments were conducted. In the first experiment pigs were fed a corn and SBM basal diet (BD), BD + 7.5% defatted algae replacing SBM, and BD + 7.5% or 15% de-fatted algae replacing corn and SBM for 6 wk. We found that the inclusion of algae in the diet to replace a significant portion of SBM lowered the average daily gain and feed efficiency of the pigs. Feeding pigs 15% defatted algae resulted in lower fecal microminerals Cu, Se, and Zn. The health status of the pigs, as determined by plasma biochemical assays, was not negatively affected. It was hypothesized that either the micromineral deficiencies, or the acid:base balance of the algae biomass negatively affected the growth performance of the pigs. A second study was conducted on the full-fat algae with and without the inclusions of either fumaric acid or the minerals found to be limited in Experiment 1. The inclusion of fumaric acid with algae alleviated the growth losses of algae fed to pigs alone. It was feasible to supplement 7.5% de-fatted algae or 10% full-fat with an organic acid for a replacement of the same amount of corn and SBM in diets for weanling pigs, without adverse effect on growth performance, biochemical status, or fecal excreta. Previous research on hydrolyzing keratinous feathers suggests that microbial proteases and reductases may be key players in their effective degradation. We describe the first heterologous protein expression of 3 predicted serine proteases and 7 predicted thioredoxin disulfide reductases from Streptomyces fradiae var. k11. The in vitro feather hydrolysis assay showed that the inclusion of reductases and proteases, with the additions of a known chemical reducing agent ([beta]-mercaptoethanol) and protease (Proteinase K), apply a synergistic effect in feather keratinolysis. As such, these cloned and expressed enzymes have promising potential for industrial uses and feather keratin.

Birds have evolved diverse plumage through sophisticated morphological modifications. The interaction of light with these modifications alters the reflectance from feathers, producing complex and directionally-variable visual signals. I hypothesize that structural modifications of the feather produce anisotropic reflectance, the direction of which is determined by the orientation of the structure of the vane. Variation in reflectance originates from the interplay of light with two classes of feather structure: its surface and subsurface volume. Different structural scales within the two structural classes influence light scattering within the UV-visible spectrum. The overall shape and surface of the feather vane (the macro-scale) and of its component members (the milli-scale) scatter light according to principles of geometric optics. Subsurface nano-scale structure in many feathers generate socalled "structural coloration," which is a purely physical optics phenomenon and can differ drastically from ordinary coloration mechanisms such as pigmentation. Iridescence, from which many feathers derive their vivid, eye-catching changeable color, is one type of structural color that varies as a function of viewing angle. This thesis presents investigations into a previously understudied aspect of avian visual signaling: directional reflectance and its relationship to milli-scale structure. Having observed that the stratified nano-scale morphology of structurallycolored plumage contours the milli-scale cortex of the vane, I determined that measurements of the milli-scale could be substituted for a more complex study of directional reflectance from the nano-scale. I thereby hypothesize that the direction of the reflectance from a vaned feather can be predicted from the orientation of its milli-scale morphology-its barbs and barbules. In collaboration with my colleagues at Cornell University, I developed non-destructive tools and methods to investigate the signaling potential of the feather. I correlate measurements of directional light scattering to the milli-scale morphology of select samples of structurally-colored bird plumage. The results of these analyses lead to a more thorough understanding of the relationships between directional reflectance and the structure of the feather itself. Having found the reflectance to be anisotropic, I demonstrate that the change in the direction of the reflectance over the surface of the vane can in fact be predicted from the orientation of the different branches of the barb. The improved understanding of the variation in directional reflectance over the surface of the feather, a phenotypic component, should allow for better comprehension of avian behavior, evolution of morphological adaptations, and the synthesis of more accurate predictive models.

การศึกษาในครั้งนี้มี จุด มุ่งหมายเพื่อวิเคราะห์หาปริมาณการสะสมของสารตะกั่ว ในขนหางของนกประจำถิ่นที่อาศํย อยู่ในนบริเวณพื้นที่ชุ่มน้ำบึงบอระเพ็ดจังหวัดนครสวรรค์ ซึ่งเป็นพื้นที่ชุ่มน้ำที่มีขนาดใหญ่ที่สุดในพื้นที่ภาคเหนือ ตอนล่างของประเทศไทย โดยเก็บตัวอย่างในช่วงเดือนมิถุนายนจนถึงเดือนธันวาคม พ.ศ.2554 ด้วยการตั้งตาข่าย ดักนกในพื้นที่จุดเก็บตัวอย่าง 7 แห่งรอบพื้นที่ เมื่อได้นกมาแล้วจะทำ การติดเครื่องหมายประจำ ตัวนกและจำแนก อุปนิสัย การกิน อาหารของนกแต่ละชนดิ ออกเป็น 3 กล่มุ แบ่งเป็นนกกิน พืช นกกิน สัตว์ และนกที่กิน ทั้ง พืชและสัตว์ จากนั้นนำ ขนหางของนกแต่ละตัวมาวิเคราะห์ในห้องปฏิบัติการ โดยใช้เครื่องอะตอมมิกแอบซอร์พชันสเปกโทร สโกปีแบบไม่ใช้เปลวไฟ (Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS) จากการวิเคราะห์ นกจำนวน 74 ตัว ในนก 24 ชนิดพันธุ์ พบว่านกกินพืชมีการสะสมของสารตะกั่วมากที่สุด ส่วนนกที่กินทั้งพืชและ สัตว์มีการสะสมน้อยที่สุด โดยที่นกกินพืช นกกินสัตว์ และนกที่กินทั้งพืชและสัตว์ มีค่าการสะสมของสารตะกั่ว อยู่ในช่วง 0.88 - 40.83, 0.18 - 28.09 และ 0.06 - 7.17 ไมโครกรัมต่อกรัม น้ำหนักแห้ง ตามลำดับ และมีค่าเฉลี่ย 14.44 ± 2.73, 7.69 ± 2.23 และ 2.84 ± 0.74 ไมโครกรัมต่อกรัม น้ำหนักแห้ง ตามลำดับ สำหรับนกที่พบว่ามีการ สะสมของสารตะกั่วมากที่สุดคือ นกสีชมพูสวน โดยมีค่าอยู่ในช่วง 40.83 ± 8.02 ไมโครกรัมต่อกรัม น้ำหนักแห้ง ความเข้มข้นของสารตะกั่วที่พบในการศึกษาครั้งนี้มีระดับต่ำเมื่อเปรียบเทียบกับนกที่อาศัยในเขตมลพิษ แต่ในบาง ชนิดพันธุ์พบว่ามีค่าใกล้เคียงกับนกที่อาศัยในเขตอุตสาหกรรม ซึ่งรายงานนี้เป็นรายงานการสะสมของสารตะกั่ว ในขนนกของประเทศไทยเป็นครั้งแรก