Early-successional habitats have become rare in much of the eastern United States, largely due to landuse change, forest maturation and the disruption of natural disturbance regimes. In addition to providing nesting habitat for shrubland species of high conservation concern, wildlife openings may be an important habitat for mature-forest birds during the postfledging period – a critical phase in the avian lifecycle with the potential for high mortality. The habitat requirements of birds during this time period are poorly understood. In this study I examined the relationship between habitat and landscape characteristics on; 1) the abundance of forest nesting birds in shrubland habitat during the postfledging season, and 2) the reproductive success of shrubland bird species. And lastly, I also examined the relationship between avian body condition and seed dispersal, with a focus on comparing native and invasive species. I found that the abundance of forest birds was strongly influenced by landscape characteristics, as well as food abundance and structurally complex vegetation. Shrubland birds varied in their response to habitat variables, but overall productivity was positively related to taller vegetation structure, and was negatively related to lower-dense vegetation. Frugivore diets were generalized, yet they selected native fruit more often than invasive fruit, and invasive fruit negatively affected condition. My findings are consistent with the results of previous studies of habitat use among postfledging birds, and suggest that, like for forest birds, habitat requirements for shrubland birds during the postfledging period differ from those during the nesting season. Hopefully these results will encourage other studies of this important, but poorly understood stage of the avian lifecycle.

Forelimbs in many mammals are used in both locomotion and the acquisition of food. In bats, the forelimbs are highly specialized for flight, but the thumb is free to preform other functions. Using morphological data from museum specimens and field observations of feeding behavior, I documented how Neotropical leaf-nosed bats (family: Phyllostomidae) use their thumbs during feeding, and examined how thumb structure and function are linked with diet. I then used these data to test when changes in thumb morphology and feeding behaviour evolved, focusing on two specific time points: the evolution of frugivory in phyllostomids; and the diversification point at the base of the clade Stenodermatinae, which are hard canopy fruit specialists. I found that size-corrected thumb length was weakly associated with diet, but the frequency and duration of thumb use were higher in frugivorous species than in their insectivorous counterparts. Likewise, the function for which frugivores used their thumbs differed from insectivores, although variation in specific thumb movements could not be teased apart in the analyses. When I modeled selective regimes of diet, I found that species that consumed fruit showed selection for increased frequency and duration of thumb movements, but there was no evidence of selection for increased thumb length at either of the two evolutionary time points tested. This suggests that a shift in how thumbs are used during feeding, and not thumb morphology, may be linked to a transition from a mainly insectivorous diet to frugivory in phyllostomid bats.

No description available.

Seed dispersal is crucial for plants to colonize new habitats and facilitate gene flow between populations. However, Pleistocene extinctions of large-bodied fruit-eating and seed-dispersing animals, known as ‘megafrugivores’, may have hindered the dispersal of plants with large fruits (> 4cm fruit length – ‘megafruits’). Plants with megafruits are common across the flora of Madagascar, especially within the palm (Arecaceae) family. This dissertation investigates the macro-ecological and micro-evolutionary consequences of dispersal limitation on palms with megafruits in Madagascar. Specifically, I investigated three key aspects: (i) turnover or beta-diversity of palms on Madagascar and the distribution of their dispersal-related traits, (ii) the genetic diversity and genetic structure of three palms with megafruits compared to one palm with small fruits, and (iii) population size and migration rate changes over time of several Malagasy palm species with different ecological characteristics. To address these questions, historical ranges of extinct megafrugivores were reconstructed based on fossil sites, and data on extant frugivores, human activities, and climate were collected. Fieldwork in Madagascar provided genetic data for 12 palm species across 46 populations, from which I generated double digest restriction-site associated DNA sequencing data. Various interdisciplinary methods were employed, including redundancy analyses, variation partitioning, linear mixed effect models, species distribution models, and demographic modelling. The findings indicate that the current turnover of palms in Madagascar is primarily influenced by extant frugivores and climate, with limited impact from extinct frugivores. Surprisingly, there is no evidence of decreased genetic diversity or increased genetic differentiation in megafruited palms due to the loss of their megafrugivore dispersers. Genetic diversity is positively associated with human population density but negatively influenced by road densities, possibly reflecting habitat fragmentation by humans. Connectivity between populations is linked to the number of shared extinct and extant (mega)frugivore species, for megafruited and small-fruited palm populations, respectively. This highlights the importance of past long-distance dispersal events by megafrugivores and human-mediated dispersal possibly maintaining connectivity for megafruited palms. Population declines are observed across palms since the Last Glacial Maximum, particularly in humid forest species rarely used by humans, while humid forest species with megafruits show recent migration disruption. In contrast, palm species with smaller fruits that are highly used by humans show less pronounced declines and more stable historical migration rates. Overall, this dissertation illustrates that while the role of megafrugivores as seed dispersers is still evident in the genome of megafruited palms, other factors such as human-mediated dispersal and climate have an influence over the distribution, genetics and demographic histories of palms in Madagascar. It further shows how integrating genetic data with ecological data on species distributions, climate, human activities, can provide novel insights into the drivers of different facets of biodiversity of such a diverse group of plants such as palms.:Chapter 1 - General introduction ....................................................................................... 7 Background and problem statement...................................................................................... 7 Plant seed dispersal, fleshy fruits and frugivory ............................................................ 7 Megafauna and megafruits ............................................................................................ 9 Thesis scope .......................................................................................................................... 12 Madagascar as a model system .................................................................................... 12 Palms as a model system .............................................................................................. 16 Thesis aims and importance ................................................................................................. 19 Overview of methodologies used ......................................................................................... 19 Field data collection ..................................................................................................... 19 Double digest restriction-site associated DNA (ddRAD) .............................................. 21 Outline of the thesis ............................................................................................................. 22 Chapter 2 - Megafrugivores as fading shadows of the past: extant frugivores and the abiotic environment as the most important determinants of the distribution of palms in Madagascar .................................................................................................................... 25 Chapter 3 - Genomic signatures of past megafrugivore-mediated dispersal in Malagasy palms ............................................................................................................................. 39 Chapter 4 - Insights into the demographic history of Malagasy palms: exploring the role of global change and species-specific characteristics ........................................................... 57 Chapter 5 – General discussion ....................................................................................... 73 Summary and key findings.................................................................................................... 73 The fate of megafruited plants in the post-megafrugivore era ........................................... 74 Vulnerability and resilience in megafruited plants .............................................................. 76 Understanding the complex role of humans in the distribution and genetics of megafruited plants ……………………………………………………………………………………………………………………………..77 The influence of abiotic factors over the distribution and genetics of Malagasy palms ..... 78 Outlook ................................................................................................................................. 79 References ...................................................................................................................... 83 Appendix ...................................................................................................................... 101 Appendix Chapter 2 ............................................................................................................ 101 Appendix Chapter 3 ............................................................................................................ 123 6 Appendix Chapter 4 ............................................................................................................ 145 Summary ...................................................................................................................... 159 Zusammenfassung ........................................................................................................ 163 Acknowledgments ........................................................................................................ 169 Curriculum Vitae ..................................................................................................................... 171 List of publications and scientific presentations .................................................................... 171 Selbstständigkeitserklärung……………………………………………………………………………………….……..168

The decline of kereru (Hemiphaga novaeseelandiae) may limit dispersal of large-seeded plants in New Zealand, but the consequences of this are unknown. I determined kereru disperser effectiveness by modelling seed dispersal distances (using seed retention times and movement patterns). Mean seed retention time was significantly longer for larger-seeded species, ranging from 37-181 minutes. Wild radiotracked kereru were sedentary, remaining at one location for up to 5.25 hours. The mean flight distance was 77 m and the maximum was 1, 457 m. Estimated mean seed dispersal distances for tawa (Beilschmiedia tawa), puriri (Vitex lucens), and fivefinger (Pseudopanax arboreus) were 95, 98, and 61 m respectively. Kereru dispersed 66-87% of ingested seeds away from the parent tree, with 79-88% of seeds dispersed <100 m and < 1% dispersed over 1,000 m. In a field seed-fate experiment, "pre-human" conditions (cleaned seeds, low density, away from parent, and protected from mammals) increased survival compared to "post-human" conditions (whole fruits, high density, under parent, not protected) for both taraire (Beilschmiedia tarairi; 15% vs. 2% survival to one year respectively) and karaka (Corynocarpus laevigatus; 60% vs. 11% to two years, respectively). Fruit diameter varied considerably within karaka, taraire, and tawa, although theoretically not enough for them to be swallowed by other birds. Nevertheless, other birds are reported to occasionally take fruits of nearly all large-seeded species. Small tawa seeds produced smaller seedlings in the glasshouse; therefore selection of only smaller seeds by alternative dispersers may negatively affect tawa recruitment. Kereru are generally not gape-limited, and fruit size preferences were independent of mean fruit size. Kereru provide effective dispersal by moving most seeds away from the parent, and enhancing seed and seedling survival. Therefore, both dispersal failure and introduced mammals negatively affect the regeneration of large-seeded trees in New Zealand.

Orientador: Mauro Galetti Rodrigues / Resumo: Invasões biológicas são uma das principais ameaças à biodiversidade, razão pela qual é campo de interesse de investigações científicas dos ecólogos. Os Neotrópicos abrigam uma das maiores riquezas de espécies do planeta e ao longo dos últimos anos vem sofrendo um aumento expressivo no número de introduções de espécies exóticas. Uma delas é o javali Sus scrofa e suas raças cruzadas com porcos domésticos, que em sua forma silvestre e de vida livre chamamos suídeos asselvajados. Ao longo dessa tese procuro investigar algumas das consequências ecológicas da invasão dessa espécie, assim como apresentar um panorama do controle populacional empregado hoje no Brasil, buscando sempre que possível fazer uma discussão dos resultados aplicada ao manejo da espécie. No Capítulo 1 mostro como a introdução acentuada dessa espécie ocorrida nos últimos 20 anos no Brasil fez com que ela se distribuísse amplamente por todo território nacional, principalmente nas regiões Sul, Sudeste e Centro-Oeste. No Capítulo 2 eu procurei fazer uma avaliação da efetividade do papel ecológico de frugivoria e dispersão de sementes prestado por esses animais. O Capítulo 3 mostra como as paisagens agrícolas estão subsidiando a invasão dos suídeos asselvajados potencializando a expansão da espécie e no Capítulo 4 busco revelar o papel do invasor no deslocamento do nicho trófico dos pecarídeos nativos.Já o Capítulo 5 apresenta um breve relato da interação entre os suídeos asselvajados e morcegos vampiros e, ao final... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Biological invasions are one of the main threats to biodiversity, which is why it is a field of interest for scientific investigations by ecologists. The Neotropics are home to one of the planet's greatest species richness, and over the last few years it has been experiencing a significant increase in the number of exotic species introduction. One of them is the wild boar Sus scrofa and their crossed-breeds with domestic pigs, that in its free-living wild-form we call wild pigs. My effort throughout this thesis is to investigate some of the ecological consequences of the invasion of this species, as well as present an outlook of the population control employed in Brazil, always seeking to make a discussion of the results applied to the management of the species. In Chapter 1 I show how the severe introduction of this species that occurred in the last 20 years in Brazil has made it widely distributed throughout the country, especially in the South, Southeast and Midwest regions. In Chapter 2 I evaluated the effectiveness of the ecological role of frugivory and seed dispersal provided by these animals. Chapter 3 shows how agricultural landscapes are subsidizing the invasion of wild pigs enhancing the species' expansion. In Chapter 4 I seek to reveal the role of the invader in displacing the trophic niche of native peccaries and Chapter 5 presents a brief account of the interaction between wild pigs and vampire bats. In the end, Chapter 6 outlines a profile of the methods and mo... (Complete abstract click electronic access below) / Doutor

O papel do mico-leão-dourado ( Leontopithecus rosalia) como dispersor de sementes na Reserva Biológica União foi avaliado pelo acompanhamento mensal de dois grupos de micos, de dezembro de 1998 a dezembro de 2000, num total de 871,9h de observações no campo. No período de estudo os micos se alimentaram dos frutos de 57 espécies de árvores de pelo menos 17 famílias, ingerindo sementes de 39 espécies,das quais 23 foram colocadas para germinar em laboratório e/ou no campo. Leontopithecus rosalia pode ser considerado como agente dispersor legítimo para as espécies estadas, porque as sementes de todas as espécies germinaram, mesmo que em baixas porcentagens, após a ingestão. Também foi avaliada a velocidade de germinação das sementes. Estes primatas não apresentam um efeito consistente na germinação final de sementes, pois beneficiam algumas espécies, enquanto prejudicam a porcentagem e/ou velocidade da germinação de outras. Para as espécies de frutos mais consumidas foram anotados o tamanho e formato das sementes engolidas, o número de árvores visitadas, além dos hábitats de ocorrência das árvores e dos locais onde as fezes foram depositadas. O tempo de retenção das sementes no trato digestório e a distância de dispersão foram medidos, bem como foram procuradas sementes predadas e digeridas nas fezes. O tempo médio de passagem para as sementes das espécies ingeridas foi de 1,1 + 0,3h e a distância média de dispersão de 107,8 + 70,6m, sendo que de modo geral as sementes dispersadas por mamíferos não são depositadas próximo às árvores parentais. O hábitat de deposição das fezes foi adequado para a germinação das sementes para 88,9% das espécies testadas, estando de acordo com o ambiente das árvores visitadas pelos micos-leões. O mico-leãodourado é um dos primatas mais ameaçados de extinção do mundo, e estudos sobre seu comportamento e ecologia irão contribuir para a preservação da espécie, de seu hábitat, e da Reserva Biológica União, uma das últimas áreas de Mata Atlântica de Baixada Costeira do Estado do Rio de Janeiro. / The role of the golden lion tamarins (Leontopithecus rosalia) as a seed disperser was studied in União Biological Reserve. Two groups of golden lion tamarins were studied during 24 months from December 1988 to December 2000, on a total of 871.9h. During the study period the tamarins fed on fruits of 57 species of trees at least from 17 families. Seeds from 39 species were ingested, and of them, 23 were put to germinate in lab and/or in the field. Leontopithecus rosalia can be considered as a legitimate seed disperser for the tested species, because seeds of all species germinated after ingestion, even in low ercentages. It was still considered the seed germination velocity. These primates do not have a consistent effect on seed germination, since benefit the germination percentage and/or velocity of some species and decrease of others. It was noted the size and shape of swallowed seeds from most frequently eaten species, the total number of visited trees, the habitat where these trees occur and where the faeces were deposited. The retention time of the seeds in the gut and the dispersion distance was noted, and damage and digested seeds were searched in the faeces. The mean time of gut passage from seeds of ingested species was 1.1+0.3h and the mean distance of dispersion was 107.8 + 70.6m, and the seeds dispersed by mammals were not usually defecated near the parental trees. The habitats of faecal deposition and of visited trees were the same in 88.9% of tested species, being possibly appropriated for seed germination and establishment. The golden-liontamarin is one of the most threatened primates in the world, and studies on their behaviour and ecology will contribute to preserve the species the habitat, and the União Biological Reserve, one of the last areas of lowland Atlantic Forest of southeast Brazil.

Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-30Bitstream added on 2014-06-13T20:21:33Z : No. of bitstreams: 1 rother_dc_dr_rcla.pdf: 2462027 bytes, checksum: c33bd50a18fd50beab5b4f95e4d965a4 (MD5) / Em florestas tropicais, ainda são incipientes os estudos que tratam da influência dos bambus na dinâmica da vegetação. Pela grande capacidade de se expandir rapidamente no ambiente seja por crescimento vegetativo ou por produção massiva de sementes, os bambus promovem alterações significativas na estrutura das comunidades vegetais. Desta forma, esse estudo teve como objetivo avaliar o ciclo de vida das plantas em ambientes com (B) e sem bambus (SB) em uma área de floresta Atlântica densamente ocupada pelo bambu nativo Guadua tagoara. Os objetivos específicos deste estudo foram separados em capítulos. Para o capítulo 1, conhecer a composição de aves associadas aos ambientes com e sem bambus, identificar as aves que compõem a guilda de dispersores de sementes de Euterpe edulis, Sloanea guianensis e Virola bicuhyba e avaliar o potencial de dispersão das aves registradas em censos. Para o capítulo 2, avaliar o padrão espacial dos estágios iniciais da regeneração da comunidade de plantas nos ambientes B e SB. Finalmente para o capítulo 3, quantificar as perdas de propágulos e as probabilidades de transição entre cada etapa demográfica das três espécies de plantas selecionadas, e identificar os gargalos demográficos do recrutamento que podem colapsar a regeneração natural das três espécies de plantas nos ambientes B e SB. Verificamos que nos ambientes B foi registrado maior número de espécies de aves do que em ambientes SB. A maioria das aves registradas em censos nos dois ambientes foi insetívora, seguida por espécies frugívoras. A efetividade da dispersão de Euterpe, Sloanea e Virola, esteve restrita a um pequeno grupo de dispersores efetivos. As aves que mais contribuíram para a dispersão de Virola ocorreram mais freqüentemente em B. Este padrão foi similar para Sloanea, enquanto Euterpe apresentou um padrão misto, com algumas espécies de aves... / Studies about the bamboo influence in the plant dynamic process are still incipient. Given that bamboos are able to quickly expand in environment by either vegetative growth or massive seed production, bamboos promote significant changes in plant community structure. Thus, this work aimed at assessing the plant life cycles in bamboo (B) and non bamboo stands (NB) in an Atlantic forest area where the native bamboo Guadua tagoara occurs at high densities. The specific goals of this study were showed in chapters. For chapter 1, to know bird species associated with bamboo and non bamboo stands, identify the birds which belong to seed dispersers guild of Euterpe edulis, Sloanea guianensis and Virola bicuhyba and evaluate dispersal effectiveness and potential contribution to seed dispersal for the three plant species. For chapter 2, assess the spatial pattern of early regeneration stages of plant communities in B and NB stands. Finally, for chapter 3, quantify propagule losses as well as the probabilities of transition between each stage for all three plant species, and identify the demographic bottlenecks in recruitment that could collapse natural regeneration of the three plant species in B and NB stands. We verified that a higher number of bird species was registered in B stands than in NB. Most of registered birds in both B and NB stands were insectivorous followed by frugivorous species. The dispersal effectiveness of Euterpe, Sloanea and Virola depended on a restricted subset of effective bird dispersers. Birds which mostly contributed to the seed dispersal of Virola occurred more frequently in B. This pattern was similar for Sloanea while Euterpe exhibited a mixed pattern with some bird species contributing to the dispersal in the B stands and other species contributing in NB stands. We conclude that a substantial number of frugivorous bird species can favor borders of bamboo patches... (Complete abstract click electronic access below)

The decline of kereru (Hemiphaga novaeseelandiae) may limit dispersal of large-seeded plants in New Zealand, but the consequences of this are unknown. I determined kereru disperser effectiveness by modelling seed dispersal distances (using seed retention times and movement patterns). Mean seed retention time was significantly longer for larger-seeded species, ranging from 37-181 minutes. Wild radiotracked kereru were sedentary, remaining at one location for up to 5.25 hours. The mean flight distance was 77 m and the maximum was 1, 457 m. Estimated mean seed dispersal distances for tawa (Beilschmiedia tawa), puriri (Vitex lucens), and fivefinger (Pseudopanax arboreus) were 95, 98, and 61 m respectively. Kereru dispersed 66-87% of ingested seeds away from the parent tree, with 79-88% of seeds dispersed <100 m and < 1% dispersed over 1,000 m. In a field seed-fate experiment, "pre-human" conditions (cleaned seeds, low density, away from parent, and protected from mammals) increased survival compared to "post-human" conditions (whole fruits, high density, under parent, not protected) for both taraire (Beilschmiedia tarairi; 15% vs. 2% survival to one year respectively) and karaka (Corynocarpus laevigatus; 60% vs. 11% to two years, respectively). Fruit diameter varied considerably within karaka, taraire, and tawa, although theoretically not enough for them to be swallowed by other birds. Nevertheless, other birds are reported to occasionally take fruits of nearly all large-seeded species. Small tawa seeds produced smaller seedlings in the glasshouse; therefore selection of only smaller seeds by alternative dispersers may negatively affect tawa recruitment. Kereru are generally not gape-limited, and fruit size preferences were independent of mean fruit size. Kereru provide effective dispersal by moving most seeds away from the parent, and enhancing seed and seedling survival. Therefore, both dispersal failure and introduced mammals negatively affect the regeneration of large-seeded trees in New Zealand.

O papel do mico-leão-dourado ( Leontopithecus rosalia) como dispersor de sementes na Reserva Biológica União foi avaliado pelo acompanhamento mensal de dois grupos de micos, de dezembro de 1998 a dezembro de 2000, num total de 871,9h de observações no campo. No período de estudo os micos se alimentaram dos frutos de 57 espécies de árvores de pelo menos 17 famílias, ingerindo sementes de 39 espécies,das quais 23 foram colocadas para germinar em laboratório e/ou no campo. Leontopithecus rosalia pode ser considerado como agente dispersor legítimo para as espécies estadas, porque as sementes de todas as espécies germinaram, mesmo que em baixas porcentagens, após a ingestão. Também foi avaliada a velocidade de germinação das sementes. Estes primatas não apresentam um efeito consistente na germinação final de sementes, pois beneficiam algumas espécies, enquanto prejudicam a porcentagem e/ou velocidade da germinação de outras. Para as espécies de frutos mais consumidas foram anotados o tamanho e formato das sementes engolidas, o número de árvores visitadas, além dos hábitats de ocorrência das árvores e dos locais onde as fezes foram depositadas. O tempo de retenção das sementes no trato digestório e a distância de dispersão foram medidos, bem como foram procuradas sementes predadas e digeridas nas fezes. O tempo médio de passagem para as sementes das espécies ingeridas foi de 1,1 + 0,3h e a distância média de dispersão de 107,8 + 70,6m, sendo que de modo geral as sementes dispersadas por mamíferos não são depositadas próximo às árvores parentais. O hábitat de deposição das fezes foi adequado para a germinação das sementes para 88,9% das espécies testadas, estando de acordo com o ambiente das árvores visitadas pelos micos-leões. O mico-leãodourado é um dos primatas mais ameaçados de extinção do mundo, e estudos sobre seu comportamento e ecologia irão contribuir para a preservação da espécie, de seu hábitat, e da Reserva Biológica União, uma das últimas áreas de Mata Atlântica de Baixada Costeira do Estado do Rio de Janeiro. / The role of the golden lion tamarins (Leontopithecus rosalia) as a seed disperser was studied in União Biological Reserve. Two groups of golden lion tamarins were studied during 24 months from December 1988 to December 2000, on a total of 871.9h. During the study period the tamarins fed on fruits of 57 species of trees at least from 17 families. Seeds from 39 species were ingested, and of them, 23 were put to germinate in lab and/or in the field. Leontopithecus rosalia can be considered as a legitimate seed disperser for the tested species, because seeds of all species germinated after ingestion, even in low ercentages. It was still considered the seed germination velocity. These primates do not have a consistent effect on seed germination, since benefit the germination percentage and/or velocity of some species and decrease of others. It was noted the size and shape of swallowed seeds from most frequently eaten species, the total number of visited trees, the habitat where these trees occur and where the faeces were deposited. The retention time of the seeds in the gut and the dispersion distance was noted, and damage and digested seeds were searched in the faeces. The mean time of gut passage from seeds of ingested species was 1.1+0.3h and the mean distance of dispersion was 107.8 + 70.6m, and the seeds dispersed by mammals were not usually defecated near the parental trees. The habitats of faecal deposition and of visited trees were the same in 88.9% of tested species, being possibly appropriated for seed germination and establishment. The golden-liontamarin is one of the most threatened primates in the world, and studies on their behaviour and ecology will contribute to preserve the species the habitat, and the União Biological Reserve, one of the last areas of lowland Atlantic Forest of southeast Brazil.