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A biologia reprodutiva dos Amphisbaenia é uma das menos estudadas entre os répteis, havendo na literatura informações sobre o ciclo reprodutivo, dimorfismo sexual e fecundidade de poucas espécies do grupo, além de informações pontuais acerca de oviposturas. A histologia das vias genitais, da mesma forma, foi pouco estudada, tornando difícil uma melhor caracterização dos ciclos de machos e fêmeas. No Brasil são encontradas cerca de um terço das espécie do grupo, distribuídas por regiões com diferentes características macroclimáticas. Este trabalho teve por objetivo caracterizar o ciclo reprodutivo de machos e fêmeas de onze espécies brasileiras da família Amphisbaenidae, com base em dados de dissecção e histologia, e analisá-los comparativamente tendo como referência a filogenia molecular já proposta para as Amphisbaenidae do Brasil. Objetivou-se ainda realizar uma análise preliminar da relação entre os ciclos reprodutivos observados e variações sazonais de temperatura e precipitação. Para tanto, foram analisados espécimes depositados em coleções zoológicas, que tiveram suas gônadas e órgãos urogenitais examinados e medidos. Foram ainda realizadas análises histológicas de ovidutos, testículos, ductos deferentes e rins de espécimes coletados em diferentes meses do ano, para análise de sua morfologia e caracterização dos ciclos espermatogênico, de estocagem de esperma e de atividade do segmento sexual renal. Foram ainda analisados espécimes e lâminas histológicas de duas espécies da família Blanidae e uma da família Trogonophidae, permitindo uma melhor discussão das características observadas tendo como referência a filogenia do grupo. Foram analisados também dados de dimorfismo sexual de tamanho do corpo e de fecundidade. Os machos de quatro espécies de Amphisbaenidae amostradas apresentaram ciclos reprodutivos assazonais, com períodos de repouso não sincrônicos entre os indivíduos. Os machos de outras sete espécies de Amphisbaenia, duas de Blanidae e uma de Trogonophidae apresentaram ciclos sazonais. Todas as sete espécies para as quais o ciclo das fêmeas pôde ser caracterizado são sazonais nesse aspecto. Os ciclos de machos foram comparados quanto à época e duração das fases de espermatogênese, estocagem de esperma e atividade secretora do segmento sexual renal, tendo sido obtidas evidências de relação entre essas características e a filogenia do grupo. As fases reprodutivas das espécies de Amphisbaenia brasileiras são mais extensas em comparação com aquelas observadas em Blanidae e Trogonophidae. Também se obtiveram evidências preliminares da relação entre sazonalidade dos ciclos reprodutivos e variações anuais de temperatura e precipitação. Em sete espécies de Amphisbaenidae, foi observado dimorfismo sexual quanto ao comprimento rostro-cloacal ou ao comprimento da cauda. A fecundidade das fêmeas varia entre um e quatro ovos, na maioria das espécies analisadas, mas pode chegar a sete em Amphisbaena mertensi e nove em Amphisbaena trachura. / The reproductive biology of the Amphisbaenia is one of the less known among reptiles. In the literature, there are information on the reproductive cycle, sexual dimorphism, and clutch size for few species, and scarce data on clutches of eggs. Similarly, the histology of the genital tract was studied in few species, which makes difficult to characterize properly the reproductive cycles of males and females. Almost one third of the species of the group occur in Brazil, in regions with different climates. This study aimed to characterize the reproductive cycle of males and females of eleven Brazilian species of the family Amphisbaenidae, based on the dissection and histological analysis of gonads and genital ducts, and to compare the obtained data with regard to the molecular phylogeny already proposed for the Brazilian species of this family. It also aimed to analyze preliminarily the relation between the observed reproductive cycles and seasonal variations of temperature and precipitation. Specimens from zoological collections were analyzed to examination and measuring of the gonads and urogenital organs. Samples of the oviducts, testis, ductus deferens and kidneys from specimens collected in various months were also analyzed using light microscopy to characterize the cycles of spermatogenesis, sperm storage, and activity of the sexual segment of the kidney. Specimens and histology slides of two Blanidae species and one Trogonophidae species were also analyzed, allowing a better discussion of the characteristics of the reproductive cycles referring to the phylogeny of the group. Sexual size dimorphism and clutch size were also analyzed. The males of four Amphisbaenidae species presented aseasonal reproductive cycles, with testicular recrudescence and rest phases not synchronized among individuals. The males of the other seven Amphisbaenidae species, two Blanidae species and one Trogonophidae species presented seasonal reproductive cycles. The seven species for which the reproductive cycles of females could be characterized are seasonal in this regard. The male reproductive cycles were compared considering seasonality and the length of spermatogenesis, sperm storage and secretory activity of the sex segment of the kidney. Evidence of relation between the reproductive cycle characteristics and the phylogeny of the family Amphisbaenidae was obtained. The reproductive seasons of Brazilian Amphisbaenia are longer than those observed in Blanidae e Trogonophidae. Preliminary evidence on the relation between reproductive cycle seasonality and annual variations of temperature were also obtained. Seven Amphisbaenidae species presented sexual dimorphism in snout-vent length or caudal length. Clutch size varies from one to four eggs in most species, but reaches seven eggs in Amphisbaena mertensi and nine in Amphisbaena trachura.

The salamander family Sirenidae is composed of two extant genera, Siren and Pseudobranchus, each with two known species. Several questions regarding Sirenidae life history persist, and much of the available life history data for Pseudobranchus are attributed to studies of P. axanthus in northern Florida. Information on the reproductive biology of P. axanthus is limited, and historical references often suggest contradictory results. This study was undertaken to clarify information and expand on the limited data regarding P. axanthus reproductive biology, specifically for southern Florida populations. The study population was most likely the P. a. belli subspecies. P. axanthus in southern Florida exhibited year round, continuous reproduction with oviposition documented in nine months. Potential clutch size was positively correlated to female size. The largest observed potential clutch was a female with 58 pre-ovulatory oocytes. The largest observed bout was a female with 15 oviductal eggs. Female P. axanthus in southern Florida oviposited eggs singly and at total densities of 3-4 eggs/m2. Developmental time to egg hatching lasted about 30 days, larvae hatched at 16mm TL, and minimum size at female sexual maturity was 115mm TL and 72mm SVL. The reproductive biology of P. axanthus was distinctly contrasting to other members of the family Sirenidae, S. intermedia and S. lacertina, that occupy the same habitat at the same study location.

As part of a state-funded Gopher Tortoise (Gopherus polyphemus Daudin) translocation project, I monitored actively grazed improved pastures to determine if they could serve as suitable recipient sites for the threatened Gopher Tortoise displaced by human development. For cattle ranches to be considered suitable recipient sites females must be able to acquire sufficient energy to produce a clutch of viable eggs, and sufficiently high quality vegetation must be available to support juvenile recruitment into the population. Vegetation surveys were conducted to determine the composition and percent cover of plant species, especially those containing high amounts of nutrients, specifically nitrogen. Resident and relocated females were radiographed during the 2010 and 2011 nesting seasons for the presence of shelled eggs. I was able to determine clutch size and egg diameter for both relocated and resident gravid females. Mean clutch sizes were not significantly different between years. Resident females had larger mean clutch sizes than relocated females in both years, significantly so in 2011, suggesting a period of stress and adjustment for relocated females. Egg diameters were significantly larger by 2.5 to 4.5 mm in 2010 for relocated and resident females, respectively, compared to 2011. Three females were recaptured in both years and exhibited the same trend of similar clutch sizes between years but significantly smaller eggs in 2011. A total of 68 unique taxa from 31 families were found, grasses (Poaceae) were the most dominant and covered a mean of 57% of the total sampled area. Four forb species occurred at much greater percent covers than all others. However, only two species (Richardia and Desmodium) were found to have adequate nutritional content and occur at percent covers greater than five percent, indicating that forage availability may be high, but forage quality may be inadequate to support growing juveniles. Burrow surveys indicate that at least some hatchlings are able to successfully leave the nest by the presence of hatchling size burrows scattered throughout the fields, but the ratio of juveniles to eggs laid is especially low. Survivorship of eggs, hatchlings and juveniles may be too low to support a sustainable Gopher Tortoise population in improved pasture possibly because of lack of adequate forage, burrow compaction by cows, lack of available natural shelter material for protection from desiccation, and the reduced ability of movement in thick pasture grasses, especially by hatchling and yearling tortoises.

The song thrush (Turdus philomelos) was introduced to New Zealand from Britain during the mid 19th century and has become one of the most common terrestrial bird species in New Zealand. In this study, I surveyed a range of life-history traits in New Zealand song thrushes for comparison with traits of British thrushes. Clutch size, egg size and nest size have decreased, while the nestling period is shorter and the incubation period longer. This combination of changes suggests birds are investing less energy into each reproductive bout. Birds also appear unable to raise large broods, as nestling starvation is common in New Zealand, which suggests that food is limiting. I experimentally tested the ability of song thrushes to incubate enlarged clutches and broods, but productivity was not higher for enlarged broods and natural 3- and 4-egg clutches produced similar numbers of fledglings. Thus reduced clutch size may be an adaptation to the local environment. Differences in female incubation behaviour, with 3- and 4-egg clutches receiving higher levels of incubation and more visits per hour than 5-egg clutches, also suggest New Zealand thrushes have difficulty coping with clutches as large as those in Britain. The decrease in clutch size between New Zealand and Britain is in the direction and magnitude expected based on the change in latitude, which supports the hypothesis that factors affecting foraging time and food availability, such as daylength, temperature and rainfall, may be selecting for smaller clutches. Egg size was also found to have decreased in New Zealand, though this may be the result of smaller adult size. Hatchling mass was related to egg volume, but I found no effect of egg volume or clutch size on hatching success. However, nests containing more pointed eggs (i.e., abnormally-shaped eggs), had lower survival and hatching/fledgling success. Data from the national nest record database and my study both suggest that differences in song thrush productivity are the result of differential survival of nestlings. Nestling mortality due to starvation was common at Kowhai Bush, but rare in Britain, so either adult condition or food availability may be lowering reproductive success in New Zealand. High rates of nest failure (>65%) could also affect clutch size, but the strong directional selection imposed by food limitation during the nestling period suggests that increases in food supply would result in increased reproductive success even with the same levels of nest failure. When comparing clutch size throughout New Zealand, I found a significant, positive relationship with rainfall, which further suggests that food limitation may be the main factor driving changes in life-history traits of song thrushes in New Zealand.

Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 63-68). Description: viii, 68 leaves : map ; 29 cm. / The ability of the Pigeon Guillemot Cepphus columba to rear an additional chick was tested by manipulating clutch sizes. The effect of the manipulations on growth, and hatching, fledging, and egg success was measured in chicks from experimental, natural, and control nests. No significant differences were observed between the nest types. Data from 1983, 1984, 1985, and 1989 were analyzed for potential differences in reproductive success of one and two egg clutches. The ratio of one to two eggs was significantly higher in 1985 and 1989. Hatching and fledging success was significantly higher for two egg clutches in 1985 and 1989. No significant differences were observed for egg success. Egg volume was significantly greater in two egg clutches in 1983 and 1984. Egg volume was correlated with fledging but not with hatching success.

A biologia reprodutiva dos Amphisbaenia é uma das menos estudadas entre os répteis, havendo na literatura informações sobre o ciclo reprodutivo, dimorfismo sexual e fecundidade de poucas espécies do grupo, além de informações pontuais acerca de oviposturas. A histologia das vias genitais, da mesma forma, foi pouco estudada, tornando difícil uma melhor caracterização dos ciclos de machos e fêmeas. No Brasil são encontradas cerca de um terço das espécie do grupo, distribuídas por regiões com diferentes características macroclimáticas. Este trabalho teve por objetivo caracterizar o ciclo reprodutivo de machos e fêmeas de onze espécies brasileiras da família Amphisbaenidae, com base em dados de dissecção e histologia, e analisá-los comparativamente tendo como referência a filogenia molecular já proposta para as Amphisbaenidae do Brasil. Objetivou-se ainda realizar uma análise preliminar da relação entre os ciclos reprodutivos observados e variações sazonais de temperatura e precipitação. Para tanto, foram analisados espécimes depositados em coleções zoológicas, que tiveram suas gônadas e órgãos urogenitais examinados e medidos. Foram ainda realizadas análises histológicas de ovidutos, testículos, ductos deferentes e rins de espécimes coletados em diferentes meses do ano, para análise de sua morfologia e caracterização dos ciclos espermatogênico, de estocagem de esperma e de atividade do segmento sexual renal. Foram ainda analisados espécimes e lâminas histológicas de duas espécies da família Blanidae e uma da família Trogonophidae, permitindo uma melhor discussão das características observadas tendo como referência a filogenia do grupo. Foram analisados também dados de dimorfismo sexual de tamanho do corpo e de fecundidade. Os machos de quatro espécies de Amphisbaenidae amostradas apresentaram ciclos reprodutivos assazonais, com períodos de repouso não sincrônicos entre os indivíduos. Os machos de outras sete espécies de Amphisbaenia, duas de Blanidae e uma de Trogonophidae apresentaram ciclos sazonais. Todas as sete espécies para as quais o ciclo das fêmeas pôde ser caracterizado são sazonais nesse aspecto. Os ciclos de machos foram comparados quanto à época e duração das fases de espermatogênese, estocagem de esperma e atividade secretora do segmento sexual renal, tendo sido obtidas evidências de relação entre essas características e a filogenia do grupo. As fases reprodutivas das espécies de Amphisbaenia brasileiras são mais extensas em comparação com aquelas observadas em Blanidae e Trogonophidae. Também se obtiveram evidências preliminares da relação entre sazonalidade dos ciclos reprodutivos e variações anuais de temperatura e precipitação. Em sete espécies de Amphisbaenidae, foi observado dimorfismo sexual quanto ao comprimento rostro-cloacal ou ao comprimento da cauda. A fecundidade das fêmeas varia entre um e quatro ovos, na maioria das espécies analisadas, mas pode chegar a sete em Amphisbaena mertensi e nove em Amphisbaena trachura. / The reproductive biology of the Amphisbaenia is one of the less known among reptiles. In the literature, there are information on the reproductive cycle, sexual dimorphism, and clutch size for few species, and scarce data on clutches of eggs. Similarly, the histology of the genital tract was studied in few species, which makes difficult to characterize properly the reproductive cycles of males and females. Almost one third of the species of the group occur in Brazil, in regions with different climates. This study aimed to characterize the reproductive cycle of males and females of eleven Brazilian species of the family Amphisbaenidae, based on the dissection and histological analysis of gonads and genital ducts, and to compare the obtained data with regard to the molecular phylogeny already proposed for the Brazilian species of this family. It also aimed to analyze preliminarily the relation between the observed reproductive cycles and seasonal variations of temperature and precipitation. Specimens from zoological collections were analyzed to examination and measuring of the gonads and urogenital organs. Samples of the oviducts, testis, ductus deferens and kidneys from specimens collected in various months were also analyzed using light microscopy to characterize the cycles of spermatogenesis, sperm storage, and activity of the sexual segment of the kidney. Specimens and histology slides of two Blanidae species and one Trogonophidae species were also analyzed, allowing a better discussion of the characteristics of the reproductive cycles referring to the phylogeny of the group. Sexual size dimorphism and clutch size were also analyzed. The males of four Amphisbaenidae species presented aseasonal reproductive cycles, with testicular recrudescence and rest phases not synchronized among individuals. The males of the other seven Amphisbaenidae species, two Blanidae species and one Trogonophidae species presented seasonal reproductive cycles. The seven species for which the reproductive cycles of females could be characterized are seasonal in this regard. The male reproductive cycles were compared considering seasonality and the length of spermatogenesis, sperm storage and secretory activity of the sex segment of the kidney. Evidence of relation between the reproductive cycle characteristics and the phylogeny of the family Amphisbaenidae was obtained. The reproductive seasons of Brazilian Amphisbaenia are longer than those observed in Blanidae e Trogonophidae. Preliminary evidence on the relation between reproductive cycle seasonality and annual variations of temperature were also obtained. Seven Amphisbaenidae species presented sexual dimorphism in snout-vent length or caudal length. Clutch size varies from one to four eggs in most species, but reaches seven eggs in Amphisbaena mertensi and nine in Amphisbaena trachura.

Adaptation to local environments via natural selection is a powerful mechanism for population divergence and likely one of the primary causes of speciation. To understand how specific habitats shape local adaptation, it is helpful to study closely-related populations from widely differing ecosystems that have not had sufficient time to diverge by genetic drift. Throughout the following chapters I examine the distribution of morphological, behavioral, and reproductive phenotypes within and between two subspecies of the swamp sparrow. These two populations, the tidal salt marsh endemic Melospiza georgiana nigrescens and the nominant inland subspecies, M. g. georgiana were incompletely isolated from each other following the retreat of the Wisconsin glaciation. Since that time the increased nest predation, temperature, season length, salinity and tidal flow of the coastal marshes relative to inland wetlands has resulted in a number of adaptations among coastal sparrows due to natural selection, sexual selection, and phenotypic plasticity. Specifically I examine the habitat preferences of the coastal plain swamp sparrow, the difference in clutch size between the two subspecies, the rates of extrapair fertilization relative to male quality, the ecosystem-specific interactions between natural and sexual selection on plumage badges, and the role of conspecific attraction in nest placement. The environmental differences of the tidal salt marsh have played strong roles in the local adaptation and divergence of coastal plain swamp sparrows from their freshwater ancestors. Many of these divergent mechanisms may be similar among other tidal marsh endemics, although some (especially those related to sexual selection) may be specific to the swamp sparrow. In general, however, we see that the added environmental challenges of tidal ecosystems strongly alter selection regimes on a terrestrial vertebrate inhabiting this dynamic ecotone. The swamp sparrow system can further increase our understanding of how the interplay between environmental resources, sexual selection, and natural selection affects the local adaptations leading to evolutionary divergence. / Ph. D.

Agriculture and, more recently, oil and gas development have contributed to extensive degradation and loss of temperate grasslands. I investigated the landscape-scale effects of oil and gas development, and roads, on grassland birds in southern Alberta using abundance, clutch size and nesting success data collected from 2010-2014. I estimated: (i) the distance at which there are effects of edge, and effects of shallow gas well density, using piecewise regressions; (ii) the locations and extent of habitat affected by infrastructure for obligate grassland species– Baird’s Sparrow (Ammodramus bairdii), Chestnut-collared Longspur (Calcarius ornatus) and Sprague’s Pipit (Anthus spragueii); and generalist species – Clay-colored Sparrows (Spizella pallida), Horned Lark (Eremophila alpestris), Savannah Sparrow (Passerculus sandwichensis), Vesper Sparrow (Pooecetes gramineus) and Western Meadowlark (Sturnella neglecta), and (iii) the total area affected by wells and roads. My findings suggest that the effects of roads, overall, extended to further distances than edge effects associated with natural gas wells, obligate species had more habitat affected by infrastructure than generalist species and shallow gas wells affected more habitat than did oil wells, due to their greater density on the landscape. Additionally, obligates, on average, were negatively affected by proximity to edge where as generalists were more productivity closer to edge. Reducing fragmentation caused by roads, minimizing the spread of non-native vegetation and management of cattle around gas wells could improve habitat quality for these focal species. / February 2016