Dissertations / Theses on the topic 'Tree frogs'

Tree frogs adhere to surfaces using their toe pads. These pads secrete a fluid which enables them to adhere using a temporary adhesive mechanism known as wet adhesion. In keeping with the principles that govern this type of mechanism, the toe pads should be capable of adhering sufficiently and detaching effortlessly. However, the vast majority of research in this area has centred on static experiments, thus giving no real indication of the dynamic activity of the animal. Therefore, one aspect of this PhD project was to investigate the biomechanics of tree frog locomotion, focussing particularly on the kinematics and forces involved during toe pad detachment. Tree frog toe pads do indeed possess a rapid, efficient detachment mechanism, the toe pads simply peeling off of the surface from the rear, requiring very little force. The impact of this at higher scales was reflected in the force profiles of individual limbs, and in the global kinematics of the frog during locomotion. In addition to this, the wet adhesive mechanism itself was investigated by assessing the performance of tree frogs in a range of challenging conditions, including on overhangs and flooded surfaces. The latter condition compromises a key component of the wet adhesive mechanism; however, torrent frogs perpetually clamber across wet rocks in the vicinity of waterfalls, and yet are able to maintain their attachment. Therefore, the second aspect of this project was to compare the adhesive capabilities of tree- and torrent frogs, and propose explanations for the differences in their performance. Whilst comparable on dry, smooth surfaces, the adhesion of torrent frogs on rough, flooded substrates was far superior to that of tree frogs. Several explanations for this are offered, including the utilisation of a greater proportion of their ventral contact area, and a toe pad morphology that is optimised for such conditions. The results of this PhD project may provide a functional and morphological ‘blueprint’ for the development of toe pad mimics that can adhere in wet conditions.

Thesis (M.S.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 26, 2007) Includes bibliographical references.

Cladistic analyses of morphological data support a monophyletic group for Polypedates but do not support a monophyletic group for Rhacophorus. Five groups of Rhacophorus are recognized:(1) Group I: R. Appendiculatus; R. Verrucosus; R. Bisacculus; R. Everetti; R. Baliogaster and R. Cavirostris. DIAGNOSIS: post cloacal region with tubercles and/or papillae; skin on dorsum with glandular warts; tip of fingers and toes round; webbing between fingers III-IV small; dermal ridge running along outer edge of fourth finger crenulated; presence of numerous small papillae on heel; dermal ridge running along outer edge of tarsus crenulated; and webbing on toes medium or large. (2) Group II: R. Jarujini; R. Lateralis; R. Turpes; R. Edentulus; R. Monticola and R. Poecilonotus. DIAGNOSIS: presence of two papillae on heel; inner metatarsal tubercle elongate; and webbing between toe I-II large or complete. (3) Group III: R. Hoanglienensis; R. Orlovi; R. Margaritifer; R. Gauni; R. Bimaculatus; R. Angulirostris; R. Baluensis; R. Calcaneus and R. Pleurostictus. DIAGNOSIS: absence of vomerine ridge; dermal ridge along forearm smooth; absence of dermal ridge or flap running along outer edge of tarsus; webbing between fingers II-III small; and webbing between toe II-III complete. (4) Group IV: R. Reinwardtii; R. Nigropalmatus; R. Malabaricus; R. Exechopygus; R. Prominanus; R. Dulitensis; R. Htunwini; R. Kio; R. Bipunctatus; R. Rhodopus; R. Annamensis; R. Pardalis; R. Harrissoni; R. Fasciatus; R. Rufipes and R. Robinsoni. DIAGNOSIS: distance from tip of snout to nostril equal to distance from nostril to eyes; presence of dermal flap along forearm; webbing between fingers II-III almost complete or complete; webbing between fingers III-IV complete; presence of dermal flap running along outer edge of fourth finger; presence of ridge or flap on heel; webbing on toes complete; presence of supra-cloacal fold or flap; post cloacal region with ridge or flap. (5) Group V: R. Dennysi; R. Feae; R. Maximus; R. Schlegelii; R. Dorsoviridis; R. Viridis; R. Moltrechti; R. Arboreus; R. Burmanus; R. Arvalis; R. Chenfui; R. Taipeianus; R. Owstoni; R. Minimus; R. Taronensis; R. Duboisi; R. Dugritei; and R. Omeimontis. DIAGNOSIS: head shape in dorsal view sub-elliptical or semicircular; webbing on hand small or medium; webbing between fingers II-III medium; and snout shape in lateral view round or obtuse. (6) Group VI: Polypedates: P. Nasutus; P. Eques; P. Otilophus; P. Megacephalus; P. Leucomystax; P. Macrotis; P. Maculatus; P. Zed; P. Colletti; P. Mutus; and P. Cruciger. DIAGNOSIS: presence or absence of co-ossified skin between eyes; webbing between toes I-II long; webbing between fingers III-IV rudimentary; and tympanum shape oval. Genera names available: Group I - Aquixalus; Groups II-V currently are members of genus Rhacophorus but cladistic analysis of morphological data show that groups are different based on several morphological characters; Group III - Leptomantis; Group IV – Rhacophorus.

Tree frogs have evolved specialised toe pads which allow them to efficiently climb vertical surfaces. The toe pad stick by using ‘wet adhesion’ – a combination of forces produced by a thin layer of fluid between the pad and the surface which provide temporary adhesion to allow quick attachment and detachment for climbing. Most studies on tree frogs have been based on their adhesive capabilities on surfaces which are flat, clean and dry (usually glass). However, climbing tree frogs in the wild will come across a variety of surfaces which could affect their adhesive abilities. This PhD investigated whether tree frog adhesion is affected by various ‘challenging’ surfaces, which reflect conditions that tree frogs may encounter whilst climbing. These include rough surfaces, wet conditions, surfaces with loose particulate and hydrophobic surfaces. Experiments were predominantly conducted using a force transducer to measure adhesive and frictional forces of single toe pads, as well as whole animal attachment experiments involving a rotating tilting board. The toe pads of tree frogs were shown to possess a self-cleaning mechanism, whereby the pads will remove contaminants (and subsequently recover adhesive forces) through repeated use, thanks to shear movements of the pad and the presence of pad fluid which aids contaminant deposition. To investigate how torrent frogs (frogs which inhabit waterfalls) can adhere to rough and flooded surfaces, the performance of torrent frogs species Staurois guttatus was compared to a tree frog species (Rhacophorus pardalis). Torrent frogs could produce higher adhesive forces than tree frogs with their toe pads, and possess a specialised toe pad morphology (directional fluid channels on the pad periphery) which may contribute to better performance in flooded conditions. Torrent frogs utilise large areas of ventral skin to stay attached on overhanging surfaces, while tree frogs display a reduction in contact area resulting in a failure to stay attached. This combination of ability and behaviour will help torrent frogs to stay attached on the rough and flooded surfaces that make up their waterfall habitat. On rough surfaces, tree frogs showed improved (compared to smooth surface performance) performance on smaller scale roughness (asperity size <10 µm), and poorer performance on the larger scale roughnesses tested (30 – 425 µm). Interference reflection microscopy (IRM) revealed that larger asperities result in pad fluid being unable to fill the larger gaps of such surfaces, which was confirmed by adding water to rough surfaces to improve attachment performance. The soft pad does however aid in conforming to some rough surfaces, which could account for the better performance on the smaller scale roughness. Many plant surfaces exhibit hydrophobic properties, and so the adhesive performance of tree frogs on hydrophobic surfaces was compared to that on hydrophilic surfaces. It was found that the toe pads could produce similar adhesive and frictional forces on both surfaces. The pad fluids contact angles were then measured on hydrophobic surfaces using IRM, where droplets of pad fluid formed lower contact angles (and are therefore exhibiting higher wettability) than water. Though the exact composition of pad fluid is unknown, some form of surfactant must be present which aids wetting of surfaces (either a surface modification or detergent present in the fluid) to allow wet adhesion to occur - goniometer experiments of water on dried footprints on hydrophobic surfaces confirmed this. The ability to stick in a variety of conditions could provide inspiration for ‘smart’ adhesives, which mimic the adaptable adhesion of tree frog toe pads.

Estudamos o modelo dos sapos na árvore homogênea, um sistema de partículas a tempo discreto cuja dinâmica é sintetizada a seguir. No instante inicial, existe em cada vértice da árvore um número aleatório independente e identicamente distribuído de partículas; aquelas posicionadas em um vértice fixado estão ativas, as demais inativas. Partículas ativas realizam passeios aleatórios simples, independentes, a tempo discreto, com probabilidade de desaparecimento (1 - p) em cada instante. Uma partícula inativa torna-se ativa assim que seu vértice é visitado por uma partícula ativa. Consideramos nesta tese o valor crítico p_c que separa a fase em que o processo se extingue quase certamente da fase em que existem partículas ativas em todos os instantes com probabilidade positiva. Provamos um limitante superior para a probabilidade crítica p_c, o qual melhora o resultado anteriormente conhecido para o caso de configuração inicial de uma partícula por vértice. O argumento utilizado consiste na descrição do modelo dos sapos como um modelo de percolação orientada que domina processos de ramificação convenientemente definidos. Obtemos também o valor assintótico do limitante superior estabelecido, mostrando ser igual ao valor assintótico da probabilidade crítica.
We study the frog model on the homogeneous tree, a discrete-time particle system whose dynamics is summarized next. Initially there is an independent and identically distributed random number of particles at each vertex of the tree; those placed at a fixed vertex are active, the others being inactive. Active particles perform independent discrete-time simple random walks, with probability of disappearance (1 - p) at each instant. An inactive particle becomes active once its vertex is hit by an active particle. We consider in this thesis the critical value p_c that separates the phase in which the process dies out almost surely from the phase in which there exist active particles at all times with positive probability. We prove an upper bound for the critical probability p_c, which improves the formerly known result for the case of one particle per vertex initial configuration. The employed argument builds on the description of the frog model as an oriented percolation model which dominates suitably defined branching processes. We also obtain the asymptotic value of the stated upper bound, showing that it equals the asymptotic value of the critical probability.

Simple content analysis methods, such as the Bechdel test and measuring percentage of female talk time or characters, have seen a surge of attention from mainstream media and in social media the last couple of years. Underlying assumptions are generally shared with the gender role socialization model and consequently, an importance is stated, due to a high degree to which impressions from media shape in particular young children’s identification processes. For young girls, the Disney Princesses franchise (with Frozen included) stands out as the number one player commercially as well as in customer awareness. The vertical lineup of Disney princesses spans from the passive and domestic working Snow White in 1937 to independent and super-power wielding princess Elsa in 2013, which makes the line of films an optimal test subject in evaluating above-mentioned simple content analysis methods. As a control, a meta-study has been conducted on previous academic studies on the same range of films. The sampled research, within fields spanning from qualitative content analysis and semiotics to coded content analysis, all come to the same conclusions regarding the general changes over time in representations of female characters. The objective of this thesis is to answer whether or not there is a correlation between these changes and those indicated by the simple content analysis methods, i.e. whether or not the simple popular methods are in general coherence with the more intricate academic methods.

Betyg VG (skala IG-VG)

This thesis demonstrates that many frog species, when stressed or challenged, produce odours that are associated with the skin gland secretions, and that the source of these odours can vary. The role of many of these odorous compounds is still unknown. However, it would appear that some odorous compounds have a defensive function and are important components of the secretions.
Thesis (Ph.D.) - University of Adelaide, Dept. of Environmental Biology and Dept. of Soil and Water, 2002

Many arthropods and vertebrates can cling to surfaces using adhesive pads on their legs. These pads are either smooth and characterised by a specialised, soft cuticle or they are hairy, i.e. densely covered with flexible adhesive setae. Animals climbing with adhesive organs are able to control attachment and detachment dynamically while running. The detailed mechanisms of how tarsal pads generate adhesive and frictional forces and how forces are controlled during locomotion are still largely unclear. The aim of this study was to clarify the attachment mechanism of smooth adhesive pads as present in many insects and tree frogs. To understand the function of these fluid-based adhesive systems, I characterized their performance under standardized conditions. To this end, experiments were conducted by simultaneously measuring adhesion, friction, and contact area in single adhesive pads. The first result of this study showed that friction in stick insect attachment pads is anisotropic: Attachment pads regularly detached when slid away from the body. Further analyses of "immobilized" arolia revealed that this anisotropy is not caused by an increased shear stress in the proximal direction, but by the instability of the tarsus when pushed distally. In the second part of this study, I analysed the role of the pad secretion present in insects and tree frogs. In stick insects, shear stress was largely independent of normal force and increased with velocity, seemingly consistent with the viscosity effect of a continuous fluid film. However, measurements of the remaining force two minutes after a sliding movement showed that adhesive pads could sustain considerable static friction in insects and tree frogs. Repeated sliding movements and multiple consecutive pull-offs of stick insect single legs to deplete adhesive secretion showed that on a smooth surface, friction and adhesion strongly increased with decreasing amount of fluid in insects. In contrast, stick insect pull-off forces significantly decreased on a rough substrate. Thus, the secretion does not generally increase attachment but does so only on rough substrates, where it helps to maximize contact area. When slides with stick insect arolia were repeated at one position so that secretion could accumulate, sliding shear stress decreased but static friction remained clearly present. This suggests that static friction in stick insects, which is biologically important to prevent sliding, is based on non-Newtonian properties of the adhesive emulsion rather than on a direct contact between the cuticle and the substrate. % Analogous measurements in toe pads of tree frogs showed that they are also able to generate static friction, even though their pads are wetted by mucus. In contrast to the mechanism proposed for insects, static friction in tree frogs apparently results from the very close contact of toe pads to the substrate and boundary lubrication. In the last section of this study, I investigated adhesive forces and the mode of detachment by performing pull-off measurements at different velocities and preloads. These experiments showed that preload has only an increasing effect on adhesion for faster pull-offs. This can be explained by the viscoelastic material properties of the stick insect arolium, which introduce a strong rate-dependence of detachment. During fast pull-offs, forces can spread over the complete area of contact, leading to forces scaling with area. In contrast, the pad material has sufficient time to withdraw elastically and peel during slow detachments. Under these conditions the adhesive force will concentrate on the circumference of the contact area, therefore scaling with a length, supporting models such as the peeling theory. The scaling of single-pad forces supported these conclusions, but large variation between pads of different stick insects did not allow statistically significant conclusions. In contrast, when detachment forces were quantified for whole insects using a centrifuge, forces scaled with pad contact area and not with length
Viele Arthropoden und Vertebraten können sich mit Hilfe tarsaler Haftorgane an Oberflächen festhalten. Diese Organe sind entweder glatt, mit einer spezialisierten, weichen Cuticula oder haarig, d.h. dicht besetzt mit mikroskopisch kleinen, biegsamen Hafthaaren. Mit Haftorganen kletternde Tiere können während des Laufens Haftkräfte dynamisch kontrollieren. Die genaueren Mechanismen, mit denen Adhäsions- und Reibungskräfte erzeugt werden und mit denen die Kräfte während des Laufens schnell kontrolliert werden können, sind allerdings noch immer weitgehend unklar. Das Ziel dieser Arbeit war es, den Haftmechanismus von glatten Haftorganen bei Insekten und Baumfröschen näher aufzuklären. Um die Funktion dieser flüssigkeitsbasierten Haftsysteme zu verstehen, charakterisierte ich ihr Adhäsions- und Reibungsverhalten unter standardisierten Bedingungen. Dazu führte ich Experimente an einzelnen Haftorganen durch, bei denen ich gleichzeitig Adhäsion, Reibung, und Kontaktfläche erfasste. Das erste Ergebnis dieser Arbeit war, dass die Reibung von Insektenhaftorganen von der Bewegungsrichtung abhängt. Ein Haftorgan, das vom Körper weg bewegt wird (distale Richtung), löst sich meist von der Oberfläche ab. Weitere Untersuchungen an Haftorganen bei fixiertem Tarsus zeigten, dass die Richtungsabhängigkeit nicht durch eine erhöhte Scherspannung in der proximalen Richtung hervorgerufen wird, sondern durch die Instabilität des Tarsus, wenn der Fuß vom Körper weg bewegt wird. Im zweiten Teil der Arbeit untersuchte ich die Rolle des Haftsekrets bei Stabheuschrecken und Baumfröschen. Bei Stabheuschrecken war die Scherspannung unabhängig von der Normalkraft und nahm mit der Bewegungsgeschwindigkeit zu, scheinbar in Einklang mit der viskosen Reibung eines durchgehenden Flüssigkeitsfilms. Jedoch ergaben Scherspannungsmessungen bei Stabheuschrecken und Fröschen selbst zwei Minuten nach einer Gleitbewegung ein beträchtliches Maß an statischer "Rest"-Reibung. Um den Einfluss geringer werdender Haftflüssigkeit zu untersuchen, wurden wiederholte Gleitversuche sowie aufeinanderfolgende Ablöseversuche auf glatten Oberflächen durchgeführt. Diese Experimente zeigten, dass sowohl die Reibungs- als auch die Adhäsionskraft mit abnehmender Flüssigkeitsmenge anstieg. Im Gegensatz hierzu nahm die Adhäsionskraft auf rauen Oberflächen mit abnehmender Haftflüssigkeitsmenge ab. Demzufolge führte die Haftflüssigkeit nur auf rauen Oberflächen zu einer Vergrößerung der Kontaktfläche und zu einer Erhöhung der Adhäsionskraft. Reibungskräfte auf glatten Oberflächen wurden bei Stabheuschrecken umso geringer, je häufiger Reibungsversuche an ein und der selben Stelle durchgeführt wurden (um die Menge an Haftflüssigkeit zu erhöhen). Dennoch blieb immer eine statische Reibung vorhanden. Das Vorhandensein von statischer Reibung ist biologisch wichtig um das unfreiwillige Ausrutschen zu verhindern. Meine Ergebnisse weisen darauf hin, dass die Haftreibung bei Insekten nicht auf direkte Kontakte zwischen Cuticula und Untergrund zurückzuführen ist, sondern auf die (scherverdünnende) nicht-Newtonschen Eigenschaften des zweiphasigen Haftsekrets. Analoge Messungen an Haftzehen von Baumfröschen zeigten, dass auch diese statische Reibungskräfte erzeugen können, obwohl sie von einem flüssigen Schleim benetzt sind. Im Gegensatz zu dem bei Insekten gefundenen Mechanismus, entsteht bei Fröschen die statische Reibung wahrscheinlich durch Trockenreibung und den sehr nahen Kontakt zur Oberfläche. Im letzten Teil dieser Arbeit untersuchte ich Adhäsionskräfte und den Ablösevorgang durch Haftkraftmessungen bei verschiedenen Geschwindigkeiten und Normalkräften. Diese Experimente zeigten, dass die Normalkraft nur bei schnellem Ablösen zu höheren Adhäsionskräften führt. Dies ist durch die viskoelastischen Materialeigenschaften der Stabheuschrecken-Arolien erklärbar, die zu einer starken Geschwindigkeitsabhängigkeit des Ablösevorgangs führen. Bei schnellem Ablösen breiten sich die Kräfte über die gesamte Kontaktzone aus, was zu einer Flächenskalierung der Adhäsion führt. Im Gegensatz dazu hat das Haftorgan bei einem langsamen Ablöseprozess genügend Zeit, sich elastisch zurückzuziehen und abzuschälen. Unter diesen Bedingungen konzentriert sich die Kraft am Rand der Kontaktzone, wodurch die Adhäsionskräfte mit einer Länge skalieren, wie z.B. von der "peeling" Theorie vorhergesagt. Die Skalierung von Einzelbein-Haftkräften bestätigte diese Schlußfolgerungen, aber die starke Variation zwischen verschiedenen Stabheuschrecken erlaubte es nicht, diese statistisch abzusichern. Im Gegensatz dazu zeigten die Haftkräfte ganzer Insekten, welche mit Hilfe einer Zentrifuge gemessen wurden, eine deutliche Flächenskalierung

In dense mating aggregations, such as insect and anuran choruses, signals produced at the same time can overlap and interfere with one another, reducing the ability of receivers to discriminate between individual signals. Thus, evolution by sexual selection is expected to result in mating signal timing strategies that avoid overlap. Patterns of signal alternation between competing males are commonly observed in leks and choruses across taxa. In some species, however, signalers instead deliberately overlap, or ‘synchronize’, their mating signals with neighboring conspecifics. Given the assumed high cost of reduced mate attraction when signals overlap, mating signal synchronization has remained an evolutionary puzzle. Synchronization may be beneficial, however, if overlapping signals reduce the attraction of nontarget receivers (predator avoidance hypothesis). Synchronized signals could also constructively interfere, increasing female attraction to the mating aggregation (the beacon effect hypothesis). I investigate these functions of synchronized signaling in two species of tree frogs that synchronize their mating calls: the pug-nosed tree frog (Smilisca sila) and the Ryukyu Kajika frog (Buergeria japonica). To examine the trade-offs imposed by call synchronization in each species, I conduct a series of field and laboratory playback experiments on target (female frogs) and nontarget (eavesdropping predators) receivers of frog calls. Results from these experiments support both hypotheses, suggesting that synchronized frog calls can reduce the attraction of predators and attract mates to the chorus. In addition, I found reduced preferences for fine-scale call timings in female S. sila and B. japonica, deviating from the expected preferences observed in many other anuran and non-anuran species. Thus, while males may enjoy multiple benefits from synchronized mating signals, relaxed sexual selection for non-synchronous signals may be key to the evolution and maintenance of mating signal synchrony.

碩士
國立中興大學
獸醫學系暨研究所
105
Spot-legged tree frogs （ Polypedates megacephalus ） as a foreign species and it reduced habitat area and food of native tree frogs after the rapid propagation in Taiwan. In recent years, some groups have carried out alien species removal plan for the spot-legged tree frogs, but the methods of euthanasia are still in line with the humanitarian way to be sure. The most common anaesthesia agents used for bath immersion in frogs including of tricaine, benzocaine, and clove oil. None of above can be considered to be optimal for amphibians due to their high variability in terms of effectiveness, reliability, safety and reversibility. Azaperone is butyrophenone derivatives a kind of neuroleptic drug with sedative and antiemetic effects, which is used mainly as a tranquilizer in veterinary medicine. Dimethyl sulphoxides （DMSO） is one of the earliest and most widely studied penetration enhancers and enhances the transdermal permeation of a variety of drugs like B- blockers and other antihypertensive drugs. The objective of this study to determine the sedation effect of the combination azaperone and DMSO in differentand propotions find out the best combination for immersion anaesthesia in spot-legged tree frogs. The study comprised three phases. The first phase was carried out to identify the concentration of azaperone-DMSO combination capable of producing anaesthetic induction in the frogs. The second phase was aimed at testing the concentrations in other eight additional animals. The third phase was aimed at testing the most effective combination in two times the sedation time. Heart rate, respiratory rate, righting, myotatic corneal reflexes and nociceptive withdrawal reflex were measured at 5 min intervals until normal righting reflex was observed. Azaperone 800 mg/L combined with 12.5% （v/v） DMSO administered via immersion produced the best effective anaesthesia in spot-legged tree frogs. The average duration of producing anaesthetic induction was 767±86 seconds and the recovery time was 1823.63±572.09 seconds. Only one of the frogs enrolled in the study died but the anaesthesia and long-term complications in the others did not occur. However, undesired side-effects likely skin rash, myoclonus and prolonged recovery, were noticed during the perianaesthetic period. This is of one of the first studies of anaesthesia in the shrub frogs and offer an effective sedation in spot-legged tree frogs by the azaperone- DMSO immersion anaesthesia.

碩士
國立花蓮教育大學
生態與環境教育研究所
95
The purpose of this research was to understand the reproductive ecology of Chinese Tree Frog (Hyla chinensis). This research was conducted at Yuanshan , Yilan County from February 2005 to May 2006. The breeding population and their reproductive behaviors were investigated. The breeding season of Chinese Tree Frog lasted form March to September at Yilan. Frogs’ activities during the breeding season, measured as (the number of the frogs being caught ) / night, were significantly correlated with the accumulative rainfall one day before the investigating day. The number of the egg masses was positively correlated with the average temperature and the accumulative rainfall of the month. Frogs’ reproductive peak was the beginning of the breeding season (March) and the typhoon seasons (July and August). At night under different weathers the males chorused at different times. The males’ chorus would last for 24 hours, and then their calling intensity would be weakened. Before the daytime rain, the humidity rose suddenly, and then the males would start to chorus. The habitats of the females were significantly higher than the males’. The heights of the males’ habitats have shown a significantly negative correlation with the humidity, but not with the temperature, the captured time intervals and the body lengths. The females’ habitats were significantly positive correlated with the temperature, and significantly negative correlated with the humidity and the body lengths, but were not correlated with the captured time intervals. The amplexus and oviposition of Chinese Tree Frog lasted 74 minutes and they lay 288 eggs in 32 minutes. The females preferred to mate with males whose body length were 77% to 98% of females’ body length. Chinese Tree Frog’s reproductive activities were influenced by the rainfall strongly. The beginning time and the duration of the males’ choruses were affected by the weather. The females’ oviposition was also influenced by the rainfall. The rainfall change caused by climatic change may influence the reproduction of Chinese Tree Frog. Therefore the understanding of Chinese Tree Frog’s reproductive ecology will contribute to the conservation of amphibians.

碩士
國立東華大學
自然資源與環境學系
102
Polypedates megacephalus has been an invasive species in Taiwan, since 2006. It’s likely to have a negative impact on ecological of Taiwan, because of their high reproductive and high population density. Diet analysis is a basic and important project for understanding ecological characteristics of animal. Stomach contents were gotten by dissection in this study. Pali Waziwei was chosen as the study site, due to its large population size of P. megacephalus and being easy to sample. The study began in August 2012, for a period of one year. The results suggested that P. megacephalus is a non-ant feeding species with broad diets, the non-breeding seasons were its main feeding period, and individuals usually use a sit-and-wait feeding behavior during this period. Blattellidae is the most important food resource for P. megacephalus because it has highest in number percentage, frequency of occurrence, index of relative importance and availability. The diet competition between P. megacephalus and native frogs are not obvious in spring and in summer. According to this study, we suggest to put more effort on removing P. megacephalus in non-breeding season, which are their main feeding period and it’s easier to detect them. Furthermore, a better effect of control can be got by using the feeding preferences of P. megacephalus to maintain habitat management.

碩士
國立臺灣師範大學
生物研究所
88
ABSTRACT The reproductive behaviors of the Farmland green tree frog (Rhacophorus arvalis) were studied at Yunling in central Taiwan from April to September 1999. The investigation took fifty-eight days in the field. The toe clipping and the waist-banded marking methods were employed to mark frogs. Rhacophorus arvalis shows obvious sexual dimorphism and in general, females are larger than males in body length Female mean snout-vent length (SVL) is 62.2±2.7 mm and male mean SVL is 46.2±2.3 mm. We have observed that the breeding season of Rhacophorus arvalis lasted five months in 1999. Rhacophorus arvalis is a prolonged breeder; its reproductive peaks were in July and August. Rainfall and temperature are the two major factors that affected the reproductive activitiea. The operational sex ratio (OSR) skewed toward males (♂:♀=13.8:1). Via the minimum convex polygon method, the mean home range of the male was 185.9 m2. Via the maximum length method, the estimated mean moving distance of males was 11.7 m. Females are attracted by calls of males and actively come to mate. Females could determine which male to mate with and select the egg-depositing site. The process of egg-depositing took 92.6±21.1minutes, while the mean time from amplexus to the completion of the foamy egg spawning took 501±59.9minutes. The mean pickaback distance was 1032±851.4 cm. The number of eggs in a clutch was 386±97.1. The mating system of Rhacophorus arvalis is lek polygyny. The number of days that males stay in the breeding area and the male mating success shows a significant positive correlation. Size-assortative mating is observed during amplexus.

碩士
國立成功大學
生物學系
88
This study compares daily vocalization pattern, call properties, and energy consumption of vocalization, in altitudinal populations of moltrechti’s tree frog, Rhacophorus moltrechti. Daily vocalization pattern did not differ significantly among different periods of a reproductive season, nor among different sites at the same altitude. However, daily vocalization pattern between altitudinal populations did vary significantly. Vocalization in the high altitude frogs (Alishan, 2300 m) remained high throughout the night and also peaked at 9:00~10:00 in the morning, whereas, that in the low altitude frogs (Nanjenshan, 300 m) peaked at the beginning of the night, then decreased at midnight and remained low in the daytime. The Alishan frogs call less frequently than the Nanjenshn frogs with longer duration in each segment of the call and greater numbers of notes in the fast phase. Vocalization of the Nanjenshan frogs recorded at different temperatures in the laboratory showed that call rate decreased and both duration in each segments and the numbers of notes in fast phase of a call increased with decreasing temperature. Fundamental frequency of the call does not differ between altitudinal populations, nor at different temperatures. Oxygen consumption for the calling males increases with rising temperature and is positively related to call rates. Based on the call rates and durations recorded in the field, I estimate that the Alishan frogs spend about only 1/4 of energy used by the Nanjenshan frogs for calling and this may be the explanation for maintenance of high vocalization activity throughout the night in the Alishan frogs. Whether the differences in call properties causes differentiation between the altitudinal populations remained to be studied.

碩士
國立臺灣師範大學
生命科學研究所
93
Abstract Farmland green tree frog, Rhacophorus arvalis is an endemic species of Taiwan. Its main habitats include rice fields, bamboo plantations, and orchards. These environments are frequently disturbed through various types of human activities. Currently it is found only in limited farmlands in Yunlin, Chiayi, and Tainan counties. Apparently this species is greatly threatened by habitat fragmentations and other human activities. Farmland green tree frogs have limited dispersal capabilities due to low mobility and site fidelity. It is one of the best candidate animals to study the impacts of habitat fragmentations on wildlife. Based on their current distribution, farmland green tree frogs can be separate into four populations: north bank of Peikang stream、south bank of Peikang stream、Potz stream and Madou. A total of 120 individuals were used to analyze with partial mitochondrial COX1, cyto b and D-loop gene fragments. Haplotypes, nucleotide diversity, FST, Nm, AMOVA (analysis of molecular variance), minimum spanning network and NCA (Nested clade analysis) methods were applied. The Farmland green tree frog’s maximum intra-specific genetic variance is 0.004, which is the lowest among amphibian being investigated in Taiwan. Even the genetic variance of Madou population is 0. Molecular data showed that four populations all derived from small effective breeding populations. We suspected that the historical stochastic factors and human disturbance might play important roles in this aspect. The north and south bank of Peikang stream populations both were rapid growing. Nevertheless, Potz and Madou population have experienced a period of bottleneck. The phylogeographic evidences indicate that Potz population might come from Peikang population. Data also revealed a consistent phylogeographic pattern, and indicated the results of “past fragmentation”. This leads to low gene flow among populations and bottleneck effect. Genetic variations were lost greatly among population and formed four significantly different populations. We suggest madou population given the higher priority for species conservation in short term. Population of Peikang stream is the genetic hotspot for conservation.

碩士
國立成功大學
生物學研究所
88
This study compares daily vocalization pattern, call properties, and energy consumption of vocalization, in altitudinal populations of moltrechti’s tree frog, Rhacophorus moltrechti. Daily vocalization pattern did not differ significantly among different periods of a reproductive season, nor among different sites at the same altitude. However, daily vocalization pattern between altitudinal populations did vary significantly. Vocalization in the high altitude frogs (Alishan, 2300 m) remained high throughout the night and also peaked at 9:00~10:00 in the morning, whereas, that in the low altitude frogs (Nanjenshan, 300 m) peaked at the beginning of the night, then decreased at midnight and remained low in the daytime. The Alishan frogs call less frequently than the Nanjenshn frogs with longer duration in each segment of the call and greater numbers of notes in the fast phase. Vocalization of the Nanjenshan frogs recorded at different temperatures in the laboratory showed that call rate decreased and both duration in each segments and the numbers of notes in fast phase of a call increased with decreasing temperature. Fundamental frequency of the call does not differ between altitudinal populations, nor at different temperatures. Oxygen consumption for the calling males increases with rising temperature and is positively related to call rates. Based on the call rates and durations recorded in the field, I estimate that the Alishan frogs spend about only 1/4 of energy used by the Nanjenshan frogs for calling and this may be the explanation for maintenance of high vocalization activity throughout the night in the Alishan frogs. Whether the differences in call properties causes differentiation between the altitudinal populations remained to be studied.

碩士
臺北市立大學
地球環境暨生物資源學系環境教育與資源碩士班
104
Population distribution of species is influenced by ecological characteristics and the dispersion capacity of the species. The geological event and the environmental alteration in the history are the two important factors that decide the population structure of species nowadays. Amphibians are considered having limited migration ability. Due to the diversity of the terrain structure and latitude, the island of Taiwan is a great location to study the impact of geographic factors on the population structure of amphibians. Here, we investigated the relationship between geological factors of the island of Taiwan and the genetic and voiceprint structure of Kurixalus eiffingeri. We used mitochondrial cytochrome oxidase coenzyme Ι (cytochrome oxidase subunit Ι; COX 1) and 16S rRNA to construct the genetic structure of Kurixalus eiffingeri population. Avisoft SASLab Pro software was selected to analyze the voiceprint structure of mating calls. We used Kurixalus eiffingeri as indicator species and investigate the association among geological factors, the topology of the phylogenetic tree, and variation of mating calls.

碩士
國立清華大學
人力資源與數位學習科技研究所
105
Environmental education (EV) has been implemented for dozens of years in Taiwan, the goals of EV are waring humans to realize and discuss the issues of environments where we are living in. Most of these EV activities were designed and acted at schools; however, people may have difficulties when learning the environmental knowledge in classroom without observing the real environment in wild. This thesis proposes a situated game of wild environment based on two types of virtual reality technologies(MHD-VR and PC-VR) to motivate learners to learn the related knowledge of Taipei frog. The difference of learning outcomes, the impact of virtual reality, technology acceptance and anxiety are discussed in this research. There are 81 participants divided into two groups. The experimental group uses a HMD Virtual Reality of 40 people, and the control group uses the Desktop Virtual Reality(PC-VR) of 41 people. The experimental result indicates that the learning outcome of both groups have been improved significantly. The average scores of students with HMD Virtual Reality is better than the average scores of students with Desktop Virtual Reality, and the presence of HMD Virtual Reality is higher than Desktop Virtual Reality. Furthermore, the anxiety level of control group is as the same as the level of experimental group.

碩士
國立東華大學
自然資源與環境學系
106
The spot-legged tree frog (Polypedates megacephalus) is an alien species that colonized Taiwan in or before 2005 and it has established several distinct populations during the past ten years. I investigated the population genetic structure of the populations of spot-legged tree frog in Taiwan based on microsatellite DNA markers. Comparing the allelic diversity across 6 loci among 8 sites, the population in New Taipei City had the highest number of alleles, effective alleles and private alleles. The fixation index (FST) ranged from 0 to 0.292, showing the significant genetic differentiation among all sampling populations. The correlation between FST and the geographic distances among sites is not significant. The bottleneck effect was detected in the population of New Taipei City, Taoyun City, Changhua County and Yunlin County. The analysis of invasion history of 8 populations showed that New Taipei City population was most likely to be the first established P. megacephalus population in Taiwan.

碩士
環球技術學院
環境資源管理所
97
Abstract Farmland tree frogs（Rhacophorus arvalis）, which are endemic in Taiwan, distribute mainly in Yunlin, Chiayi and Tainan counties. They usually choose bamboo gardens as their habitats. However, the bamboo forestry in the above areas is now rapidly vanishing, thus threatens the quality of farmland tree frogs’ habitat. In order to increase incentives for bamboo farmers to preserve the habitat of farmland tree frogs, we establishing promotion mechanisms for the eco-labeled bamboo shoots for conserving farmland tree frogs on the basis of a former study about the certification system. The foreseen outcomes will not only provide supporting forces to farmland tree frog conservation, but also increase the value-added of bamboo forestry. Therefore, economy and ecology can be balanced. We chose Shanjiau Li in Dalin Township, Chiayi County as the demonstration area of our eco-labeled bamboo shoot system. Field survey, literature analysis and the ad Hoc method are adapted to establishing the certification system and the succeeding promotion mechanisms. According to the conclusions of the ad Hoc meeting, the key promotion mechanisms include: (a) the production-operation system which main tasks are to assist local farmers to set up a cooperative for bamboo production and marketing and to examine the feasibility of various business models, such as joint procurement, the shareholder system, etc; (b)the well-designed certification/ accreditation system which increase the confidence of consumers towards the eco-labeled bamboo shoot; (c)the administration system which is mostly realized by the Farmland-tree-frog Conserving and Promotion Association, will coordinate farmers, accreditation committee and consumers. (d)the education and promotion system which elevate the awareness of farmers and the general public towards this eco-labeling system. According to the results of interviews with the relevant experts, most propaganda work can be done by the relatives and friends of members. Nevertheless, internet promotion and participating related expos are also important. Concerning the future marketing channel, patterns with relatively low costs, for example, internet-ordering, joint-purchasing and farmers’ fairs, get higher priorities. About the pricing, 20 to 30 percent higher than the common market prices is suggested. Concerning the preserving techniques for bamboo shoots, the pre-cooling method is recommended during delivery. Results of ecological monitoring for farmland tree frog within the demonstrative area showed that, there were 33 habitats recorded in 2008, more than which of 2007(29). However, the areas of 82% habitats found are smaller than 5,000m2, while the corresponding number in 2007 is 65%. This finding implies that most habitats of farmland tree frogs became smaller and showed the tendency of over-dividing. We draw a zone measured 1,322,571 m2 in area which covered 26 distribution points, i.e., 42% of total sites, to mark the key area for farmland tree frog. Comparing the outcomes of the two years found that the median points of all habitats slightly moved 80 meters South. During the implementation of the demonstration project we found, with various education camp and training courses, the local community, as well as, the public, were more aware of the situation of farmland tree frogs. While we also received some queries from consumers and dealers about the eco-labeling system simply because it had not been approved by the official agriculture departments. Key words: Farmland tree frog, Promotion mechanism ,certification system, Eco-agriculture

Males of European tree frog are clustered in the chorus in order to attract females. Males were re-captured, their body size and position in chorus was recorded. Goal of this thesis was investigated a correlation between the males' body size and mating behaviour and their position in the chorus.