Saab Barracuda utvecklar och tillverkar avancerade kamouflagesystem för skydd mot upptäckt och identifiering genom signaturanpassning. Signaturanpassning är en grundläggande del av taktiska strategin för militära styrkor och uppnås genom att reducera kontrasten mot bakgrunden för ändamålsenliga våglängdsområden inom det elektromagnetiska spektrumet. I det visuella området reduceras signaturskillnader främst genom färger och mönster, vilket anpassas till målets taktiska miljö. För att kunna optimera kamouflage är det viktigt att kunna utvärdera och bedöma de olika inverkande egenskapernas effektivitet när det kommer till att reducera ett objekts signatur, vilket syftar på de egenskaper som karaktäriserar ett objekt och särskiljer den från dess omgivning. Konventionellt sett görs detta genom studier i fältmiljö. Metoden ger en verklighetsförankring men kombinationen av olika objekttyper, terränger, taktiska avstånd och miljörelaterade parametrar gör utvärderingsmomentet snabbt till en tids- och resurskrävande process. Syftet med arbetet är att ta fram en metod för virtuell utvärdering av kamouflage visuella maskeringsförmåga som bidrar till att göra framtagningen mer tids- och resurseffektiv. Tillvägagångssättet består av dokumentstudier i kombination med simuleringsstudier. Metodiken efterföljer Design research methodology (DRM) som syftar till att ge en förståelse för processer samt utveckla stöd för att förbättra eller optimera dem. Resultatet från studien bildar sammantaget med en metod för att virtuellt kunna utvärdera mönster. En 3D modell av kamouflagenätet har tagits fram och en metod för insamling av 2D bilder av terränger beskrivs. Metoden möjliggör utvärdering av maskeringsförmågan hos kamouflage på olika observationsavstånd och betraktningsvinklar där byte av mönster och bakgrunder med enkelhet kan utföras. Soldata kan anpassas till bilden för att erhålla ett visuellt, realistiskt resultat. Utvärdering görs i programmet Adobe Dimension och modellen har skapats i Autodesk 3ds Max. Inställningar för att efterlikna det fysiska nätets mekaniska samt spektrala egenskaper approximativt togs fram genom att subjektivt jämföra den optiska konstrasten mellan simulering och foto. Resultatet presenterades för forskning- och utvecklingsavdelningen på Saab Barracuda med 14 personer närvarande. / Saab Barracuda develops and manufactures advanced camouflage systems for protection against detection and identification through signature management. Signature management is a fundamental part of the tactical strategy of military forces and is achieved by reducing the contrast against the background of appropriate wavelength ranges within the electromagnetic spectrum. In the visual field, signature differences are mainly reduced by colors and patterns, which are adapted to the target's tactical environment. In order to enable optimization of camouflage, it is important to be able to evaluate the effectiveness of the various influencing properties when it comes to reducing an object's signature, which further refers to the characteristics of an object that distinguish it from its surroundings. Nowadays, this is mainly done through field studies. The method provides an accurate picture of the dynamic range that occurs in reality, but the combination of different types of objects, terrains, tactical distances and environmental-related parameters quickly makes the evaluation process a time and resource consuming process. The purpose of this thesis is to develop a method for virtual evaluation of a camouflage visual signature in order to make the development process more time and resource efficient. The approach consists of document studies in combination with simulation studies. The methodology used to achieve the method follows Design research methodology (DRM), which aims to provide an understanding of processes and develop support to improve or optimize them. The results of the study together form a workflow for virtual evaluation of different patterns. A 3D model of the camouflage net has been developed and a method for collecting 2D images of terrains is described. The method enables evaluation at different observation distances and viewing angles where patterns and backgrounds easily can be changed. Sun and weather data can be adapted to the image to visually obtain a realistic result. Evaluation is done in Adobe Dimension and the model has been created in Autodesk 3ds max. The settings used to mimic the mechanical and spectral properties of the physical camouflage were approximated by subjectively comparing the optical contrast between simulation and photo. The result was presented for the research and development team on Saab Barracuda with 14 persons being present.

No description available.

In the field of control systems, testbeds are a pivotal step in the validation and improvement of new algorithms for different applications. They provide a safe, controlled environment typically having a significantly lower cost of failure than the final application. Vision systems provide nonintrusive methods of measurement that can be easily implemented for various setups and applications. This work presents methods for modeling, removing distortion, calibrating, and rectifying single and two camera systems, as well as, two very different applications of vision-based control system testbeds: deflection control of shape memory polymers and trajectory planning for mobile robots. First, a testbed for the modeling and control of shape memory polymers (SMP) is designed. Red-green-blue (RGB) thresholding is used to assist in the webcam-based, 3D reconstruction of points of interest. A PID based controller is designed and shown to work with SMP samples, while state space models were identified from step input responses. Models were used to develop a linear quadratic regulator that is shown to work in simulation. Also, a simple to use graphical interface is designed for fast and simple testing of a series of samples. Second a robot testbed is designed to test new trajectory planning algorithms. A templatebased predictive search algorithm is investigated to process the images obtained through a lowcost webcam vision system, which is used to monitor the testbed environment. Also a userfriendly graphical interface is developed such that the functionalities of the webcam, robots, and optimizations are automated. The testbeds are used to demonstrate a wavefront-enhanced, Bspline augmented virtual motion camouflage algorithm for single or multiple robots to navigate through an obstacle dense and changing environment, while considering inter-vehicle conflicts, iv obstacle avoidance, nonlinear dynamics, and different constraints. In addition, it is expected that this testbed can be used to test different vehicle motion planning and control algorithms.

Thesis (MMil)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: SUPPLY CHAIN MANAGEMENT APPLICABLE TO THE SOUTH AFRICAN ARMY CAMOUFLAGE CLOTHING COMMODITY There are many reasons for the popularity of the supply chain or the supply chain management concept. Through globalisation, entities are forced to look for more effective ways to coordinate the flow of goods and material between facilities, into and out of the business. Customers are consistently demanding products that are delivered faster, exactly on time, and with no damage. Supply chain management is the systemic, strategic coordination of the traditional business functions and the tactics across these business functions within a particular entity and across businesses within the supply chain, for the purpose of improving the long-term performance of the individual entities and the supply chain as a whole. One key objective of supply chain management is to lower the costs required to provide the necessary level of customer service, in order to gain a competitive advantage within a market segment. To be fully effective in today’s competitive environment, entities must expand their integrated behaviour to incorporate customers and suppliers. Low cost and differentiated service help build a competitive advantage for the supply chain. When entities take up a supply chain management philosophy, they must determine and establish management practices that permit them to operate and behave consistent with this philosophy. Performance measurement provides the necessary assistance for performance improvement in pursuit of supply chain excellence. The efficient and effective management of this supply chain with performance measurement and internal controls establishes a solid base for competitive advantage. The SA Army camouflage clothing logistics reveals elements of improvement, as compared to supply chain management principles. Camouflage clothing forms an important element of the total supplies of a soldier in sustaining military and warfare capabilities. Camouflage clothing logistics in the SA Army is a complex mix of physical entities, processes and rules that is governed by mostly conceptual concepts and principles. The SA Army lacks an integrated supply chain philosophy and clear supply chain management principles. Supply chain management can enhance camouflage clothing logistics in the SA Army, if the principles are properly applied. The SA Army is a military institution with peacekeeping operations as their core function. The manufacturing and distribution of clothing is not a core function of the SA Army and can therefore be outsourced to address most of the concerns raised under the present system. Although it would be difficult and cumbersome to implement an integrated supply chain, with supply chain management philosophy and practices, the principle will enhance efficiency and effectiveness in today’s economic environment. The level of outsourcing and the effectiveness of control will determine the degree of success the SA Army will achieve. / AFRIKAANSE OPSOMMING: AANVOERKETTINGBESTUUR VAN TOEPASSING OP DIE SUID-AFRIKAANSE LEëR KAMOEFLEERDRAG KOMMODITEIT Daar is verskeie redes vir die populariteit van die aanvoerketting of die aanvoerkettingbestuurskonsep. Globalisasie het entiteite gedwing om ondersoek in te stel na meer effektiewe maniere om die vloei van goedere en materiaal, tussen fasilitieite, asook in en uit die entiteit te koördineer. Kliënte eis gereeld produkte wat vinniger, presies op tyd en met geen skade afgelewer word. Aanvoerkettingbestuur is die sistemiese, strategiese koordinasie van al die tradisionele besigheidsfunksies, asook taktieke oor hierdie besigheidsfunksies, binne ‘n entiteit en oor besighede binne die aanvoerketting, met die doel om die langtermyn prestasie van die individuele entiteite en die aanvoerketting as geheel te verbeter. Een sleuteldoel van aanvoerkettingbestuur is om kostes te verminder. Hierdie kostes word geassosieer met ‘n sekere vlak van kliëntediens, wat voorsien moet word om ‘n kompeterende voordeel in die marksegment te verkry. Om in vandag se kompeterende omgewing ten volle effektief te wees moet entiteite hul geïntegreerde gedrag uitbrei om kliënte en verskaffers in te sluit. Lae koste en gedifferensieërde diens help om kompeterende voordeel binne die aanvoerketting te bou. Sodra entitieite ‘n aanvoerkettingfilosofie aanneem, moet hulle bestuurspraktyke bepaal en vastel hoe om in lyn met dié filosofie op te tree en te funksioneer. Prestasiemeting voorsien die nodige riglyn vir prestasieverbetering in die strewe na aanvoerketting uitnemendheid. Kamoefleerdrag vorm ‘n belangrike element in die uitrusting van die soldaat wanneer militêre- en oorlogsvermoë hanteer moet word. Kamoefleerdraglogistiek in die SA Leër is ‘n komplekse mengsel van fisiese entiteite, prosesse and reëls wat meestal deur konseptuele beginsels geregeer word. Die SA Leër kamoefleerdrag logistiek reflekteer elemente van verbetering, wanneer vergelyk word met aanvoerkettingbestuursbeginsels. Die SA Leër kort ‘n geïntegreerde aanvoerkettingfilosofie, asook duidelike aanvoerkettingbestuursbeginsels. Aanvoerkettingbestuur kan die kamoefleerdrag logistiek in die SA Leër verbeter, as die beginsels reg toegepas word. Die SA Leër is ‘n militêre instelling met vredesoperasies as primêre funksie. Die vervaardiging en verspreiding van klerasie is nie die SA Lëer se primêre funksie nie en kan daarom geprivatiseer word. Dit sal primêr die probleme wat onder die huidige stelsel voorkom, aanspreek. Al word dit voorsien dat dit moeilik en omslagtig sal wees om ‘n geïntegreerde aanvoerkettingfilosofie en -beginsel in die SA Leër te implimenteer, dit die doeltreffendheid en doelmatigheid van die huidige stelsel in vandag se ekonomie sal verbeter.

This thesis addresses the mechanisms regulating the evolution and maintenance of colour polymorphism in the shrimp Hippolyte obliquimanus. It includes four chapters that illustrate, in an integrative approach, the ecological and behavioural consequences of different camouflage and habitat use strategies selected in main colour morphs. In the first chapter entitled Camouflage through colour change: mechanisms, adaptive value, and ecological significance, the physiological and structural mechanisms underpinning colour change, and hence camouflage, in different species were detailed within a general framework. Also in this section, both the adaptive value and the ecological and evolutionary implications of these processes were discussed. In the second chapter entitled Shape, colour plasticity, and habitat use indicate morph-specific camouflage strategies in a marine shrimp morph-specific colour change and habitat selection were investigated as potential mechanisms affecting camouflage efficiency and the natural distribution of H. obliquimanus colour morphs between macroalgal habitats formed by Sargassum furcatum and Galaxaura marginata. Moreover, morph-specific morphology and behavioural traits were also assessed. Shrimp showing a homogeneous coloration (H) changed colour when placed in colour-mismatching backgrounds and also exhibited a more robust shape associated to high substrate fidelity and specialization. On the other hand, striped translucent shrimp (ST) were not capable of colour change and showed high mobility, consistent with a more streamlined shape and a generalised use of algal habitats. In the third chapter entitled The adaptive value of camouflage and colour change in a polymorphic shrimp visual models and predation trials were used to test the adaptive value of camouflage and colour change of H. obliquimanus colour morphs against colour-contrasting macroalgae, which provide different levels of colour concealment. The low colour discrimination predicted by a visual model of a seahorse predator for pink shrimp against the red weed Galaxaura was directly translated to lower detection and consumption rates on this morph by captive seahorses in a laboratory experiment, demonstrating the high adaptive value of camouflage in this species. Finally, in the fourth chapter entitled Habitat-dependent niche partitioning between colour morphs of the algal-dwelling shrimp Hippolyte obliquimanus the trophic ecology of H and ST morphs when using Sargassum and Galaxaura habitats were assessed through stable isotope analysis. Morphs showed different isotopic signatures only in Galaxaura, where the supply of food resources are limiting, leading to a tropic niche diversification between H and ST shrimp and a probable relaxation of intra-specific competition. Conversely, in Sargassum, where resources are abundant, morphs coexistence is possible even without niche partitioning. Altogether, the results of this thesis contributed to a better understanding of the adaptive value and the underlying mechanisms controlling for the maintenance of colour polymorphism in H. obliquimanus. From both an ecological and evolutionary perspective, morph-specific strategies of camouflage and habitat use likely promote the stability of shrimp populations in a spatially heterogeneous and markedly seasonal habitat. / Esta tese aborda os mecanismos que regulam a evolução e manutenção do polimorfismo de cor no camarão Hippolyte obliquimanus ao longo de quatro capítulos que ilustram de forma integrada as consequências ecológicas e comportamentais das distintas estratégias de camuflagem e de uso do habitat selecionadas nos principais morfótipos da espécie. No Capítulo 1, intitulado Camouflage through colour change: mechanisms, adaptive value, and ecological significance, são detalhados de maneira geral os mecanismos fisiológicos e estruturais responsáveis pelo processo de mudança de cor e obtenção de camuflagem em diferentes espécies de animais. Nessa seção também é detalhado o valor adaptativo e as implicações ecológicas e evolutivas desses processos. No Capítulo 2, intitulado Shape, colour plasticity, and habitat use indicate morph-specific camouflage strategies in a marine shrimp, são investigados os processos de mudança de cor e de seleção de habitat como possíveis mecanismos reguladores dos padrões de camuflagem e de distribuição dos morfótipos de cor de H. obliquimanus entre os bancos das algas Sargassum furcatum e Galaxaura marginata. Além disso, também são avaliadas diferenças morfológicas e comportamentais entre os morfótipos na utilização dos habitats vegetados. Camarões caracterizados por uma coloração homogênea (H) mudam de cor quando em contato com substratos de coloração diferente à sua, exibindo também uma morfologia mais robusta e um comportamento de alta fidelidade e especialização aos substratos de macroalgas. Por outro lado, camarões transparentes listrados (TL) não mudam de cor e apresentam elevada mobilidade, consistente com uma morfologia mais hidrodinâmica e com uso mais generalizado dos habitats estudados. No Capítulo 3, intitulado The adaptive value of camouflage and colour change in a polymorphic shrimp, são utilizados modelos visuais e experimentos de predação para testar o valor adaptativo da camuflagem e mudança de cor em diferentes morfótipos do camarão H. obliquimanus quando estes estão associados a macroalgas que fornecem diferentes graus de semelhança cromática. O baixo grau de discriminação cromática previsto para camarões rosa em associação à alga vermelha Galaxaura através da modelagem visual de um predador (cavalo-marinho) resultou em baixas taxas de detecção e predação desse morfótipo por cavalos-marinhos em um experimento de laboratório, demonstrando um alto valor adaptativo da camuflagem nessa espécie. Por fim, no Capítulo 4, intitulado Habitat-dependent niche partitioning between colour morphs of the algal-dwelling shrimp Hippolyte obliquimanus, a ecologia trófica dos morfótipos de cor H e TL na utilização dos bancos de Sargassum e Galaxaura é avaliada através de análises de isótopos estáveis. Os morfótipos de cor mostraram diferenças nas razões isotópicas apenas em Galaxaura, onde a abundância de recursos alimentares é limitante, levando à diversificação de nicho trófico entre camarões H e TL e uma provável redução da competição intraespecífica. Por outro lado, em Sargassum, onde há abundância de recursos, a coexistência entre os morfótipos é possível mesmo sem partição de nicho ecológico. Em conjunto, os resultados obtidos nessa tese detalham tópicos centrais sobre os mecanismos reguladores e o valor adaptativo do polimorfismo cromático em H. obliquimanus. Dentro de uma abordagem ecológica e evolutiva, as diferentes estratégias de camuflagem e de uso de habitat dos morfótipos de cor parecem ser essenciais para o equilíbrio populacional da espécie, uma vez que os bancos de macroalgas utilizados como habitat pelos indivíduos são bastante heterogêneos e sua disponibilidade varia sazonalmente.

Τα φύλλα κάποιων φυτών γίνονται παροδικά κόκκινα, λόγω της συσσώρευσης ανθοκυανινών. Εξετάστηκαν δύο από τις πολλές υποθέσεις που έχουν διατυπωθεί για το ρόλο των χρωστικών αυτών στα φύλλα: ο φωτοπροστατευτικός τους ρόλος και η εμπλοκή τους στις σχέσεις φυτών και φυτοφάγων εντόμων. Χρησιμοποιήθηκαν δύο είδη φυτών (Quercus coccifera και Cistus creticus) τα οποία παρουσιάζουν ενδοειδική ποικιλομορφία όσον αφορά στη συσσώρευση ανθοκυανινών στα φύλλα τους. Στο Q. coccifera, τα νεαρά φύλλα κάποιων ατόμων είναι κόκκινα και κάποιων άλλων πράσινα, ενώ κατά την ενηλικίωση τους γίνονται όλα πράσινα. Τα ώριμα φύλλα του C. creticus το καλοκαίρι είναι πράσινα (“πράσινη” περίοδος) αλλά συσσωρεύονται παροδικά ανθοκυανίνες στα ώριμα φύλλα κάποιων θάμνων κατά τη περίοδο του χειμώνα (“κόκκινη” περίοδος), ενώ γειτονικά άτομα παραμένουν πράσινα. Συγκρίθηκαν παράμετροι του in vivo φθορισμού της χλωροφύλλης, τα επίπεδα των συστατικών του κύκλου των ξανθοφυλλών και των ολικών φαινολικών, τα φάσματα ανακλαστικότητας και η ένταση της φυτοφαγίας, σε κόκκινα και πράσινα φύλλα από αντίστοιχους φαινοτύπους που αναπτυσσόντουσαν στο ίδιο ενδιαίτημα. Δεν διαπιστώθηκε κάποιο συγκριτικό πλεονέκτημα (ή μειονέκτημα) των ανθοκυανικών φύλλων όσον αφορά στη φωτοσυνθετική τους λειτουργία ή στην ανθεκτικότητά τους έναντι της φωτοαναστολής, στις συνθήκες που αναπτύσσονται. Στα διαφορετικού χρώματος, νεαρά φύλλα του Q. coccifera, είναι σαν να γίνεται ένας “συμβιβασμός” όπου στα κόκκινα φύλλα φτάνει λιγότερο φως στους χλωροπλάστες (ή/και λειτουργούν οι ανθοκυανίνες ως αντιοξειδωτικά), ενώ τα πράσινα φύλλα έχουν μεγαλύτερη δυνατότητα για μη φωτοχημική απόσβεση λόγω μεγαλύτερης συγκέντρωσης συστατικών του κύκλου των ξανθοφυλλών. Στο C. creticus, κατά την “πράσινη” περίοδο τα μελλοντικά ερυθρά φύλλα παρουσιάζουν φωτοσυνθετική και φωτοπροστατευτική κατωτερότητα, σε σχέση με τα φύλλα του πράσινου φαινοτύπου, που όμως δεν τους δημιουργεί πρόβλημα, όσο οι περιβαλλοντικές συνθήκες είναι ευνοϊκές. Κατά τη δυσμενή εποχή του χειμώνα, τα πράσινα φύλλα αυξάνουν την ικανότητα τους για μη φωτοχημική απόσβεση, ενώ τα κόκκινα όχι. Μπορεί σε αυτή την περίπτωση οι ανθοκυανίνες να αποτελούν μια προσαρμογή ώστε να αντισταθμίζεται αυτή η κατωτερότητα και να μειώνεται ο κίνδυνος φωτοαναστολής. Ωστόσο, τα νεαρά κόκκινα φύλλα του C. coccifera, είχαν υποστεί λιγότερες απώλειες από φυτοφάγα. Η μη ύπαρξη διακυμάνσεων στο φάσμα ανακλαστικότητας των κόκκινων φύλλων στην περιοχή 400-700 nm, σε συνδυασμό με τις δυνατότητες της χρωματικής όρασης πολλών φυτοφάγων εντόμων, υποδεικνύει ότι τα ερυθρά φύλλα πιθανόν να μην μπορούν εύκολα να εντοπιστούν από τους θηρευτές τους. Επίσης, κάποια φυλλοβόρα έντομα μπορεί να αποφεύγουν τα κόκκινα φύλλα, γιατί εκεί γίνονται περισσότερο ευδιάκριτα από τα αρπακτικά. Η αυξημένη συγκέντρωση των κόκκινων φύλλων σε φαινολικά μπορεί να αποθαρρύνει την περεταίρω κατανάλωση μετά από τυχαία προσέγγιση. / Leaves of some plants are transiently red due to anthocyanin accumulation. Among the many hypotheses for the function of foliar anthocyanins, two are tested in this field study: the sun screen, photoprotective function against excess visible light and the handicap signal against herbivory. Two plant species (Quercus coccifera and Cistus creticus) were used which display intraspecies variation in the expression of the anthocyanic character. Young leaves of some individuals of Q. cocifera are transiently red due to anthocyanin accumulation, while redness disappears upon maturation. Mature leaves of C. creticus are green during summer (“green” period) but in some individuals they turn transiently to red during winter (“red” period), while neighboring individuals remain green. In vivo chlorophyll fluorescence parameters, xanthophyll cycle pool sizes, reflectance spectra, total phenolics and extent of herbivory were compared in green and red leaves sampled from the corresponding phenotypes occupying the same habitat. An appreciable photosynthetic and photoprotective superiority (or inferiority) of anthocyanic leaves in both plant species under field conditions was not found. It seems that there is a compromise in differently coloured young leaves of Q. coccifera where red leaf chloroplasts enjoy less light due to its attenuation by anthocyanins (and/or anthocyanins participate in photoprotection through their anti-oxidant capacity) while green leaf chloroplasts are better equipped to dissipate excess light as heat through their higher size of xanthophyll cycle pool. During the “green” period, future red leaves of C. creticus show photosynthetic and photoprotective inferiority compared to the leaves of the green phenotype which is possibly insignificant for plant performance during the favourable period of the year. During the winter stress green leaves increase their ability for non-photochemical quenching while red phenotypes do not. In this case, anthocyanins may be an adaptation to compensate for this deficiency and alleviate the risk of photodamage. However, young red leaves of Q. coccifera are less attacked by insect consumers. The leveling of reflectance in anthocyanic leaves throughout the 400-570 nm band together with the spectral discriminating capabilities of leaf eating insects, may make red leaves less discernible to some insects. Furthermore, some insect herbivores may avoid red leaves because there are more discernible to predators. Incidental attack may be a posteriori discouraged due to the high phenolic investment of red leaves.

This thesis addresses the mechanisms regulating the evolution and maintenance of colour polymorphism in the shrimp Hippolyte obliquimanus. It includes four chapters that illustrate, in an integrative approach, the ecological and behavioural consequences of different camouflage and habitat use strategies selected in main colour morphs. In the first chapter entitled Camouflage through colour change: mechanisms, adaptive value, and ecological significance, the physiological and structural mechanisms underpinning colour change, and hence camouflage, in different species were detailed within a general framework. Also in this section, both the adaptive value and the ecological and evolutionary implications of these processes were discussed. In the second chapter entitled Shape, colour plasticity, and habitat use indicate morph-specific camouflage strategies in a marine shrimp morph-specific colour change and habitat selection were investigated as potential mechanisms affecting camouflage efficiency and the natural distribution of H. obliquimanus colour morphs between macroalgal habitats formed by Sargassum furcatum and Galaxaura marginata. Moreover, morph-specific morphology and behavioural traits were also assessed. Shrimp showing a homogeneous coloration (H) changed colour when placed in colour-mismatching backgrounds and also exhibited a more robust shape associated to high substrate fidelity and specialization. On the other hand, striped translucent shrimp (ST) were not capable of colour change and showed high mobility, consistent with a more streamlined shape and a generalised use of algal habitats. In the third chapter entitled The adaptive value of camouflage and colour change in a polymorphic shrimp visual models and predation trials were used to test the adaptive value of camouflage and colour change of H. obliquimanus colour morphs against colour-contrasting macroalgae, which provide different levels of colour concealment. The low colour discrimination predicted by a visual model of a seahorse predator for pink shrimp against the red weed Galaxaura was directly translated to lower detection and consumption rates on this morph by captive seahorses in a laboratory experiment, demonstrating the high adaptive value of camouflage in this species. Finally, in the fourth chapter entitled Habitat-dependent niche partitioning between colour morphs of the algal-dwelling shrimp Hippolyte obliquimanus the trophic ecology of H and ST morphs when using Sargassum and Galaxaura habitats were assessed through stable isotope analysis. Morphs showed different isotopic signatures only in Galaxaura, where the supply of food resources are limiting, leading to a tropic niche diversification between H and ST shrimp and a probable relaxation of intra-specific competition. Conversely, in Sargassum, where resources are abundant, morphs coexistence is possible even without niche partitioning. Altogether, the results of this thesis contributed to a better understanding of the adaptive value and the underlying mechanisms controlling for the maintenance of colour polymorphism in H. obliquimanus. From both an ecological and evolutionary perspective, morph-specific strategies of camouflage and habitat use likely promote the stability of shrimp populations in a spatially heterogeneous and markedly seasonal habitat. / Esta tese aborda os mecanismos que regulam a evolução e manutenção do polimorfismo de cor no camarão Hippolyte obliquimanus ao longo de quatro capítulos que ilustram de forma integrada as consequências ecológicas e comportamentais das distintas estratégias de camuflagem e de uso do habitat selecionadas nos principais morfótipos da espécie. No Capítulo 1, intitulado Camouflage through colour change: mechanisms, adaptive value, and ecological significance, são detalhados de maneira geral os mecanismos fisiológicos e estruturais responsáveis pelo processo de mudança de cor e obtenção de camuflagem em diferentes espécies de animais. Nessa seção também é detalhado o valor adaptativo e as implicações ecológicas e evolutivas desses processos. No Capítulo 2, intitulado Shape, colour plasticity, and habitat use indicate morph-specific camouflage strategies in a marine shrimp, são investigados os processos de mudança de cor e de seleção de habitat como possíveis mecanismos reguladores dos padrões de camuflagem e de distribuição dos morfótipos de cor de H. obliquimanus entre os bancos das algas Sargassum furcatum e Galaxaura marginata. Além disso, também são avaliadas diferenças morfológicas e comportamentais entre os morfótipos na utilização dos habitats vegetados. Camarões caracterizados por uma coloração homogênea (H) mudam de cor quando em contato com substratos de coloração diferente à sua, exibindo também uma morfologia mais robusta e um comportamento de alta fidelidade e especialização aos substratos de macroalgas. Por outro lado, camarões transparentes listrados (TL) não mudam de cor e apresentam elevada mobilidade, consistente com uma morfologia mais hidrodinâmica e com uso mais generalizado dos habitats estudados. No Capítulo 3, intitulado The adaptive value of camouflage and colour change in a polymorphic shrimp, são utilizados modelos visuais e experimentos de predação para testar o valor adaptativo da camuflagem e mudança de cor em diferentes morfótipos do camarão H. obliquimanus quando estes estão associados a macroalgas que fornecem diferentes graus de semelhança cromática. O baixo grau de discriminação cromática previsto para camarões rosa em associação à alga vermelha Galaxaura através da modelagem visual de um predador (cavalo-marinho) resultou em baixas taxas de detecção e predação desse morfótipo por cavalos-marinhos em um experimento de laboratório, demonstrando um alto valor adaptativo da camuflagem nessa espécie. Por fim, no Capítulo 4, intitulado Habitat-dependent niche partitioning between colour morphs of the algal-dwelling shrimp Hippolyte obliquimanus, a ecologia trófica dos morfótipos de cor H e TL na utilização dos bancos de Sargassum e Galaxaura é avaliada através de análises de isótopos estáveis. Os morfótipos de cor mostraram diferenças nas razões isotópicas apenas em Galaxaura, onde a abundância de recursos alimentares é limitante, levando à diversificação de nicho trófico entre camarões H e TL e uma provável redução da competição intraespecífica. Por outro lado, em Sargassum, onde há abundância de recursos, a coexistência entre os morfótipos é possível mesmo sem partição de nicho ecológico. Em conjunto, os resultados obtidos nessa tese detalham tópicos centrais sobre os mecanismos reguladores e o valor adaptativo do polimorfismo cromático em H. obliquimanus. Dentro de uma abordagem ecológica e evolutiva, as diferentes estratégias de camuflagem e de uso de habitat dos morfótipos de cor parecem ser essenciais para o equilíbrio populacional da espécie, uma vez que os bancos de macroalgas utilizados como habitat pelos indivíduos são bastante heterogêneos e sua disponibilidade varia sazonalmente.

Orientadores: João Vasconcellos Neto, Marcelo de Oliveira Gonzaga / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T19:28:17Z (GMT). No. of bitstreams: 1 Messas_YuriFanchini_M.pdf: 5292618 bytes, checksum: e9d4cb4630aa094506b01fcaa93c218a (MD5) Previous issue date: 2014 / Resumo: Aranhas vivem em ambientes estreitamente definidos, limitados por condições físicas, como temperatura, umidade, ventos e intensidade luminosa; e também por fatores biológicos, como o tipo de vegetação, disponibilidade de presas, competidores e inimigos naturais. A família Araneidae é a principal família de aranhas construtoras de teias orbiculares. A aranha Eustala perfida ocorre preferencialmente no interior da mata, construindo a teia próxima a uma concavidade em troncos de árvores. Possui coloração críptica semelhante a musgos e liquens, adaptação que confere à espécie dupla vantagem, pois dificilmente são percebidas por suas presas e seus predadores. A falta de estudos sobre este gênero de aranhas e sua história de vida, bem como o papel ecológico que desempenha, motivou a elaboração do presente estudo, que foi realizado na Serra do Japi ¿ Jundiaí (SP) e tem como objetivo elucidar aspectos da história natural de Eustala perfida, tais como distribuição espacial, especificidade por substrato, fenologia, flutuação da população, caracterização da teia, diversidade de presas e seus inimigos naturais. A espécie Eustala perfida ocorre em altitudes que vão desde 850 até 1294 m, sendo mais abundante em altitudes intermediárias. Todos os indivíduos foram encontrados no interior da mata, com maior ocorrência em troncos contendo musgos, líquens e concavidades, que servem como pontos de fixação para a construção das teias. A espécie foi encontrada com maior frequência em árvores com diâmetros maiores do que 30 cm e construindo suas teias em alturas de até 1,5 m. Observou-se que a população de Eustala perfida apresenta picos de frequência sucessivos dos diferentes estádios de desenvolvimento, com início nos meses quentes do ano (janeiro), quando os indivíduos começam a emergir. A população parece ter apenas um ciclo reprodutivo ao longo do ano, com picos fenológicos em todas as fases de desenvolvimento. Observou-se maior frequência de presas potenciais com até 1 mm de comprimento, sendo que os grupos mais amostrados foram Diptera e Hymenoptera. Houve diferença nas frequências de tamanho das presas potenciais e predadas por Eustala sendo que presas com mais de 1 mm de comprimento foram mais predadas do que o esperado ao acaso. Eustala perfida apresentou dinâmica e fenologia semelhante à de Misumenops argenteus (Thomisidae). Nestas duas espécies o ciclo de vida e a fenologia parecem ajustados às estações climáticas e à disponibilidade de presas. Foram encontrados sete indivíduos de E. perfida parasitados por larvas de Acrotaphus sp. (Pimplinae: Icheneumonidae). Trata-se do terceiro caso de manipulação comportamental de aranhas em sua construção de teia envolvendo parasitoides deste gênero / Abstract: Spiders live in narrowly defined environments, limited by physical conditions such as temperature, humidity, winds and light intensity; and also by biological factors such as vegetation type, prey availability, competitors and natural enemies. Araneidae is the principal family of orb-weaver spiders. The spider of the present study, Eustala perfida, occurs preferentially within the forest, along tree trunks, building its web in regions where there are concavities on the trunk. It has cryptic coloration similar to mosses and lichens, adaptation that presents a dual advantage, because the spiders are hardly perceived by their prey and also their predators. The lack of studies of this genus and its natural histories, as well as the ecological role that it plays, motivated the development of this project, which was conducted at Serra do Japi ¿ Jundiaí (SP) and aims to elucidate aspects of the natural history of Eustala perfida, such as spatial distribution, substrate specificity, phenology, population fluctuation, characterization of the web, prey diversity and natural enemies. Eustala perfida occurred at altitudes ranging from 850 to 1294 m, being significantly more abundant in intermediate altitudes. All individuals were found within the forest, with the highest occurrence in trunks containing mosses, lichens and concavities, which serve as attachment points for the construction of the web. The species was found more frequently on trees with diameters larger than 30 cm and building their webs in heights up to 1.5 m. The population dynamics of Eustala perfida is well defined, showing successive peaks of different developmental stages starting in the warm months of the year (January), when individuals begin to hatch. The population seems to have only one reproductive cycle throughout the year, with peaks in all phases of phenological development. There was a higher frequency of potential prey up to 1 mm in length, and the most sampled groups were Diptera and Hymenoptera. There were differences in the size frequencies of potential and predated prey of E. perfida, and prey with more than 1 mm in length were predated more than expected. Eustala perfida presented dynamic and phenology similar to Misumenops argenteus (Thomisidae). In these two species, the life cycle and phenology seem to set seasons and prey availability. Seven individuals of E. perfida were found parasited by Acrotaphus sp. (Pimplinae: Icheneumonidae) larvae. This is the third case of behavioral manipulation of spiders on your web construction involving this genus of wasp / Mestrado / Biodiversidade Animal / Mestre em Biologia Animal

Convergent evolution is a central theme in biology. Birds are an ideal system to examine the mechanisms underlying convergent evolution. Although bird patterning is diverse, within-feather patterns have repeatedly converged on the same four types: mottled patterns, scales, bars and spots. Other avian patterns occur, e.g. stripes, but are rare. In my thesis I examine the four main mechanisms underlying convergent evolution in plumage patterns: evolutionary genetics, evolutionary development, natural selection for signaling and camouflage. Japanese quail (Coturnix japonica) is a model system in developmental biology. Examining the developmental basis of pattern formation using molecular techniques, the dorsal patterning of embryonic quail is likely due to activation of the melanocortin-1 receptor, which is a highly conserved pathway in vertebrates. I examined whether a reaction-diffusion based theoretical model of pattern formation may predict developmental constraint in two groups that have different lifestyles and spectacular patterns: waterfowl (Anseriformes) and gamebirds (Galliformes). Tracing the evolutionary trajectory of pattern evolution with Bayesian comparative modeling there was evidence for developmental constraint in pattern evolution. Adaptive explanations may also result in convergence. Cuckoo-hawk mimicry has been demonstrated in the common cuckoo (Cuculus canorus) and the Eurasian sparrowhawk (Accipiter nisus), but may be prevalent in Old World cuckoos. Randomly selecting a parasitic cuckoo from each genera of Old World cuckoos and <8 sympatric raptors, I quantified their barred patterns using digital image analysis and found that parasitism can explain convergent evolution in the patterns of parasitic cuckoos and raptors. Patterns may have evolved due to ecological selection. Examining the patterns of 80% of all avian species worldwide, I found that habitat does not predict patterning, and that all four patterns are found in all habitats. These results demonstrate that the mechanisms of convergent evolution are diverse, and that development and natural selection have contributed to pattern evolution.

Orientadores: João Vasconcellos Neto, Marcelo de Oliveira Gonzaga / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T05:04:24Z (GMT). No. of bitstreams: 1 Souza_HebertdaSilva_M.pdf: 4147716 bytes, checksum: 886fc92941a725beb4f3c73d25b6a031 (MD5) Previous issue date: 2013 / Resumo: O grupo das aranhas é extremamente diverso e está distribuído em praticamente todos os habitats terrestres. No entanto, a ocorrência de grande parte das espécies é condicionada por fatores abióticos e bióticos bem definidos. Dessa forma, elementos como altitude, intensidade luminosa, temperatura, umidade, bem como as interações existentes com outros organismos, como a relação entre presas e predadores, podem influenciar o padrão de distribuição e os ajustes populacionais de aranhas ao longo do tempo. A vegetação é um fator determinante para a biologia de aranhas orbitelas, pois além de providenciar condições microclimáticas adequadas, fornece abrigo e pontos de apoio para a construção de teia... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The Group of spiders is extremely diverse and is distributed in practically all terrestrial habitats. However, the occurrence of most species is conditioned by abiotic and biotic factors. Thus, elements such as altitude, light intensity, temperature, humidity, as well as existing interactions with other organisms, such as the relationship between prey and predators, may influence the distribution pattern and population adjustments of spiders over time. The vegetation is a determining factor for the biology of Orb-Weavers spiders, because, in addition to providing adequate microclimatic conditions, it provides shelter and support spots for construction of webs. Eustala taquara (Araneidae) inhabits herbaceous plants and shrubs, and are difficult to be seen by blending with the dry vegetation where they lie... Note: The complete abstract is avaiable with the full electronic document / Mestrado / Biodiversidade Animal / Mestre em Biologia Animal