Thesis (M. Phil.)--University of Hong Kong, 2000. / Includes bibliographical references.

Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references.

Title from title page of PDF (University of Missouri--St. Louis, viewed February 23, 2010). Includes bibliographical references.

No description available.

Thesis (Ph.D.)--University of Wollongong, 2004. / Typescript. Includes bibliographical references: p. 169-180.

Thesis (MS)--University of Montana, 2007. / Contents viewed on March 30, 2010. Title from author supplied metadata. Includes bibliographical references.

published_or_final_version / abstract / toc / Ecology and Biodiversity / Master / Master of Philosophy

Thesis (Ph. D.)--University of Nevada, Reno, 2007. / "December, 2007." Includes bibliographical references . Online version available on the World Wide Web.

Made available in DSpace on 2014-06-11T19:23:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-05-29Bitstream added on 2014-06-13T20:10:18Z : No. of bitstreams: 1 genini_j_me_rcla.pdf: 456803 bytes, checksum: 6182367c1c334ef43c439af45aeda354 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As florestas tropicais estão entre os ambientes mais produtivos do planeta, sendo que a quantidade de frutos kg/ha pode chegar a 180-1000 kg/ha. Apesar dessa alta produtividade, a fenologia é altamente sazonal, ocorrendo períodos de escassez de recursos e alta produtividade no mesmo ano e/ou entre anos. Os frugívoros exibem uma ampla variedade de adaptações comportamentais e ecológicas para superar esses períodos de escassez. O presente trabalho avaliou as variações temporais na disponibilidade de frutos consumidos por vertebrados frugívoros na Ilha Anchieta, São Paulo, Brasil. Nós procuramos responder às seguintes questões: Os padrões de frutificação e disponibilidade de frutos diferem entre arbóreas e palmeiras? e Os padrões fenológicos de frutificação diferem entre grupos de palmeiras com diferentes síndromes de dispersão?. Os padrões fenológicos foram sazonais para ambos os grupos, no entanto, as datas de ocorrência dos eventos de frutificação foram diferentes. A produção de frutos também foi diferente entre palmeiras e arbóreas, sendo que as palmeiras constituíram mais de 80 por cento do total da biomassa coletada. Os padrões fenológicos foram diferentes entre as palmeiras com diferentes sub-síndromes de dispersão (dispersas por roedores, mistas e aves) fornecendo recursos alimentares para diferentes grupos de frugívoros ao longo do ano. As palmeiras poderiam constituir um recurso alimentar alternativo em períodos de baixa disponibilidade de frutos embora não forneçam recursos para os diferentes tipos de frugívoros da Ilha Anchieta o ano todo. / Tropical rainforest is considered one of the world s most productive habitats where fruit biomass ranges between 180-1000 kg/ha/yr. Despite this broad fruit production, phenology is highly seasonal in tropical forests, showing alternate periods of fruit scarcity and high resource production both in the same year and/or between different years. Frugivores exhibit a variety of ecological and behavioral adaptations to overcome these fluctuations. We evaluate the temporal variation in the availability of fruits consumed by vertebrate frugivores on Anchieta Island, in the Brazilian Atlantic Forest, Northeast São Paulo State. We aim to answer the following questions: Do fruiting patterns and the availability of fruits consumed by vertebrate frugivores differ between palms and trees? Do palm fruiting patterns differ among seed dispersed groups (rodent, mixed and bird)? Phenological patterns were seasonal for both trees and palms; however, the times of occurrence of fruiting differed. Fruit fall biomass was also different between trees and palms, and palms constituted more than 80 percent of the overall fruit fall biomass. Phenological patterns differed between the seed dispersed palms groups (rodent, mixed and bird seed dispersed palms) providing food resources in distinct periods for different assemblages of vertebrate frugivores. Palms may constitute an alternative food resource in periods of low fruit availability, although they do not provide resources for the entire assemblage of vertebrate frugivores on Anchieta Island all year.

Ripe fleshy fruits contain an enormous diversity of metabolites that influence ecological interactions with mutualistic and antagonistic species. This dissertation investigates the impact of fruit secondary metabolites on the foraging behavior and digestive physiology of bats (Chapters 2-4) while applying insights from basic chemical ecology to inform forest regeneration strategies (Chapter 5). The studies were conducted in northeastern Costa Rica at La Selva Biological Station. Chapter Two examines the variability and associations between nutrients and secondary metabolites within ripe Piper sancti-felicis fruits, showing that intraindividual variation of chemical traits can surpass interindividual variation and associations between chemical traits are scale-dependent, varying in strength and direction. Chapter Three explores how bats balance nutrient acquisition with defensive metabolite avoidance and the impact of metabolite consumption on bat nutrient absorption. It reveals that nutrient composition is the primary driver of bat foraging behavior and that defensive metabolites can interfere with protein absorption. Chapter Four further uses untargeted metabolomics to explore the influence of secondary metabolites on nutrient absorption, demonstrating that four commercial secondary metabolites induce dose-dependent changes in bat fecal metabolome, altering essential nutrient absorption. Chapter Five translates principles of chemical ecology into practical use by demonstrating the effectiveness of synthetic volatiles in attracting fruit bats and increasing seed rain. Taken together, this dissertation shows the impact of defensive metabolites on a key seed disperser while demonstrating the potential application of chemical ecology to address forest regeneration challenges. / Doctor of Philosophy / Fleshy fruits exhibit a remarkable chemical complexity. Fruit pulp is not only rich in essential nutrients (sugars, proteins, and lipids) but also contains a diverse array of other chemicals collectively known as secondary metabolites. These metabolites shape ecological interactions between fruits and frugivores. This dissertation focuses on understanding the ecological and physiological effects of fruit chemistry on frugivores. The studies were conducted at La Selva Biological Station in northeastern Costa Rica, focusing on fruit bats and pepper plants. Chapter two examines the relationships and variation between nutrients and toxins within ripe fruits of pepper plants (Piper sancti-felicis), finding that the chemical variation within a single plant can exceed the differences between separate plants. Also, depending on the scale studied, toxins and nutrients can be positively or negatively associated. Chapters Three and Four describe the preferences of a fruit bat (Carollia perspicillata) for nutrients and toxins, showing that nutrients are the primary driving force behind food choices and demonstrating that certain fruit toxins alter the ability of bats to absorb nutrients, including different sugars, proteins, and lipids. Chapter Five demonstrates the potential of synthetic chemical lures to attract fruit bats and enhance seed dispersal, offering a promising strategy to promote forest regeneration in degraded areas. Overall, this research demonstrates how fruit chemicals can significantly impact fruit bats, which play a crucial role in dispersing seeds and maintaining forest diversity.