Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 17 of 17 for “"species recognition"”.
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An Analysis of Species Recognition in Sympatric, Allopatric and Reciprocally Cross-fostered PEROMYSCUS CALIFORNICUS and PEROMYSCUS EREMICUS (Rodentia, Cricetidae)
… mate selection in two closely related species, Peromyscus californicus and Peromyscus eremicus. Comparisons were made between allopatric and sympatric populations and between males and females for mate selection performance. Both species made significant choice for the homospecific …
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SPECIES RECOGNITION IS DRIVING EVOLUTION OF THE ACOUSTIC MATING SYSTEM OF SHIELD BACK KATYDIDS (ORTHOPTERA: TETTIGONIIDAE: AGLAOTHORAX): BEHAVIORAL AND PHYLOGENETIC EVIDENCE
Sexual selection and species recognition are two processes that may drive evolution of mating systems and contribute to speciation. Evidence from nature is rare. I asked whether song evolution in shield-back katydids (Aglaothorax) from southern California is consistent with either of these …
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EVALUATION OF POTENTIAL PRE-MATING REPRODUCTIVE ISOLATION IN TIGER BEETLES (CARABIDAE: CICINDELINAE)
The biological species concept depends on mechanisms isolating reproduction to taxonomically define a species and to explain the disadvantages, and subsequent lack, of hybridization. In co-occurring tiger beetles (Carabidae: Cicindelinae), these between-species barriers are not readily apparent. To …
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Evidence for the Role of Ecdysteroids in the Genital Sex Pheromone of Two species of Hard Ticks, <i>Dermacentor variabilis</i> (Say) and <i>Dermacentor andersoni</i> Stiles
… in washings of the vaginal lumen of these two species. <em>D. andersoni</em> females contained larger amounts of ecdysteroids than <em>D. variabilis</em> females. Males of <em>D. variabilis</em> and <em>D. andersoni</em> responded positively to authentic ecdysone, and 20-OH-ecdysone in neutered …
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Complex Acoustical Feature Representation in the Zebra Finch Caudomedial Neostriatum (Ncm)
… (songs) to mediate individual as well as species recognition. Although behaviorally obvious, it is unclear how these discrete auditory perceptual objects are represented in the brain and linked to appropriate behavioral responses. In the caudomedial neostriatum (NCM) of the zebra finches, …
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Impacts of ocean acidification on fitness and chemical communication in a model marine invertebrate, Nereis succinea
… impacts associated with OA are variable between species. The presented research shows long-term culture (4-6months) in near future OA conditions (CO₂ enriched to pH 7.8) delays metamorphosis in the marine polychaete, Nereis succinea. Culture in pH 7.8 seawater also caused interference with the …
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Population genetic studies of economically important Gracilaria and Gracilariopsis (Rhodophyta) in the south western Cape
… and Gracilariopsis), combine to impede species recognition. Gracilaria and Gracilariopsis occur naturally from the Eastern Cape Province, South Africa to northern Namibia and the genetic variation within this widespread species or species complex is unknown. In this study, samples were …
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Phylogeography and ecology of New Zealand freshwater Amphipoda (Paracalliope, Paraleptamphopus, and Phreatogammarus)
… and distributional data. It also examines how recognition behaviour can be used to delineate potential species boundaries and to assess the role of sexual selection. The endemic genus Phreatogammarus has been found in only a limited number of sites and is not very abundant. An analysis of the …
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Cooling Machines: Exploring the Heat Mitigation Effect of Urban Trees with Computer Vision
… how these impacts vary across trees of different species and morphology. This is due to both the complexity of studying vegetation life cycles at sufficient scale, as well as due to the dispersed nature of the issue across disciplines of biology, urban climate, design, and data science. …
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Evolution of colour vision in relation to colouration in weaverbirds (Family Ploceidae) and poison dart frogs (Family Dendrobatidae)
… mate choice and rival assessment, individual and species recognition, predator avoidance, prey acquisition, and other major behavioural decisions. The ability to capitalize on colour signals and cues therefore grants a large fitness advantage, making vision and especially colour vision a key …
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Fitness for the Ark : are zoo bred amphibians ready to go back to the wild?
… important role in the management of endangered species through the reintroduction of captive-bred animals into the wild. Reintroduction is becoming a high-profile management tool for many threatened species, but it is unknown how many generations of captive breeding can influence a species’ …
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Muscular control of vocal complexity in the túngara frog (Engystomops pustulosus)
… the study of the simplest case, in which a species with a single-note mating call evolves a second note. Túngara frogs ( Engystomops pustulosus ) provide the best-known example of complex calling among frogs. The initial part of the mating call, called "whine", is always present and mediates …
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The role of echolocation in communication in a high duty cycle echolocating bat, Rhinolophus clivosus (Chiroptera: Rhinolophidae): an experimental approach
Acoustic communication plays a pivotal role in species recognition across a number of taxa. Species must therefore maintain discrete acoustic signatures to facilitate communication and avoid misidentification. The Acoustic Communication Hypothesis (ACH) thus proposes that in multispecies …
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A neuro-genetic hybrid approach to automatic identification of plant leaves
… including conservation of endangered plant species, rehabilitation of lands after mining activities and differentiating crop plants from weeds. In recent times, many researchers have made attempts to develop automated plant species recognition systems. However, the current computer-based …
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Speciation and the evolution of male breeding coloration in darters
… is a topic of much debate and study. Darters, a species-rich clade of freshwater fishes that exhibit widespread sexual dichromatism, may represent a prime example of speciation by sexual selection. I investigated mechanisms of sexual selection and reproductive isolation in two closely related, …
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Statistical and Biological Analyses of Acoustic Signals in Estrildid Finches
… and signal processing. Discrimination and recognition further require cognitive processes and supporting mechanisms in order to successfully identify and appropriately respond to signal senders. Although acoustic communication is common across birds, classical research has largely …
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Linking ecological divergence and reproductive isolation: a tale of two killifish
… combinations that are unique to each population/species (Felsenstein 1981; Rieseberg 2001; Ortiz-Barrientos, Reiland et al. 2002; Butlin 2005). Under divergence with gene flow, either very strong selection or some other mechanism that reduces recombination rates is needed to maintain different …