published_or_final_version / Pharmacology / Doctoral / Doctor of Philosophy

The natural history, population dynamics, and community ecology of five small mammals from tropical deciduous and semideciduous (arroyo) forests were studied in western Mexico. I evaluated the influence of habitat heterogeneity and productivity on species diversity, population dynamics, and patterns of resource utilization. I expected higher biomass and species diversity and denser populations in the more complex and productive arroyo forest than in the deciduous forest. Species diversity was higher in the arroyo forest but total biomass, population density and fluctuations were very similar in both forests, despite strong differences in habitat heterogeneity and productivity. Reproduction of all species was associated to seasonality in food availability. Populations of all the species had qualitatively similar temporal patterns of reproduction and population fluctuations because they used similar food resources. Peaks in reproduction and population densities coincided with peaks in food production, suggesting that food availability is a limiting factor. Species differed in variables affecting resource utilization such as body mass, diet, and habitat selection. Results indicate that food resource partitioning and macro and microhabitat preferences permit coexistence. This study suggests that habitat heterogeneity and productivity have a profound influence in population and community ecology of small mammals in the Neotropics.

The primary object of this study is to provide a checklist of the mammals occurring within the Transvaal. A general biological account of each species forms the bulk of this treatise, - discussing, in order of sequence, firstly the taxonomic status of each species as based on a study of available museum specimens. Thereafter the distribution of each species is discussed, and illustrated with a map of known distribution. Remarks are presented on the various environmental factors that may influence individual species ranges. Habitat preferences, habits, and food preferences are then discussed. Available data on breeding seasonality, as based on the monthly ratio of reproductively active and inactive females, are given. External measurements and masses of males and females are tabulated. Records of occurrence based on the number of museum specimens from each locality, and the institution where these specimens are housed, are finally listed for each species. The text is supplemented by a gazetteer, giving the latitudinal and longitudinal coordinates of all the collecting localities. This study is based on some 12 000 museum specimens, the greatest majority housed in the Transvaal Museum collections. During the field work phase of this project, 57 localities were sampled. This yielded the majority of the specimens and the greater part of the data on which this book is based. Information gained from a study of earlier collected material supplements these data files. Additional information such as sight records, field observations, and the published accounts of other scientists, have also been incorporated into the central data files and have been discussed in relation to my own findings. The results of selected studies comprise the discussion. The basic behavioural trends and mean mass of all the carnivore species of the Transvaal are employed to speculate on how interspecific competition is avoided. The distribution of all southern African mammals is employed to statistically evaluate the validity of the biotic zones previously empirically recognized for this subcontinent. The distribution patterns of Transvaal mammals are statistically analysed to subdivide the biotic zones overlying the Transvaal into community types of zoogeographical significance. Other zoogeographical phenomena are discussed in relation to regional species diversity. Reprints of papers arising from this study, and particularly the discussion, are bound in as appendices to this report. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1978.

In this investigation energy demands from offspring were varied for the MF1 mouse after litter sizes were manipulated and set to 5 pups/litter or 16 pups/litter by cross-fostering to examine the effects on immediate lactation and subsequent reproductive performance. Pups reared in manipulated large litters grew slower and were weaned lighter (half the size of pups reared in small litters) than pups reared in manipulated small litters.  Mortality of pups was high in the large litters but pups did not die in small litters. The results of a subsequent reproduction that followed the first lactation suggested an apparent cost for the female group that previously reared pups in large litters.  This is because in the subsequent reproduction, the group raised litters that were significantly (P<0.05) 12.7g less in mass than litters raised by females that previously reared pups in small litters.  This apparent cost, however, did not appear to have severe negative impact on the general reproductive performance because data showed comparable litter sizes and masses at birth, growth rates of pups, and the number and masses of pups weaned between this group and females that previously reared pups in small litters. At reproductive age, female offspring previously weaned from large litters weighted significantly (P<0.05) 5.8g less than female offspring previously weaned from small litters.  During their first breeding attempt or episode, female offspring previously weaned from large litters did not catch-up in body mass with those previously weaned from small litters.  In spite of this, the two groups ingested similar quantities of food prior to mating and during lactation.  The groups did not differ significantly (P>0.05) in efficiencies of energy utilization, milk energy output and daily energy expenditure.  Consequently, they showed comparable breeding success. Different age groups of male and female offspring previously weaned from manipulated small (5 pups/litter) or large litters (16 pups/litter) and unmanipulated normal litters (10 pups/litter) varied significantly in body mass and did not show compensatory growth at the time they were examined for susceptibility to obesity and glucose intolerance.  A batch of six months old male offspring previously weaned from litters whose mothers were fed a particular macronutrient diet during lactation did not differ significantly in body mass when they were also examined for susceptibility to obesity.  All groups and sexes showed a tendency to develop obesity when they were challenged with a diet that contained up to 45% fat by calories.  Development of obesity did not appear to depend on  a particular litter size in which the mice were previously reared and weaned or whether the mice were previously suckled by mothers that were fed a particular macronutrient diet.  However, the development of obesity exhibited sexual dimorphism with the male offspring showing a higher tendency to develop obesity than female offspring.

Titi monkeys have long been known for their complex vocal behaviour with numerous high- and low-pitched calls, which can be uttered singly or combined in more complex structures. However, up to date very little is known concerning the function, meaning and context-specific use of these vocal utterances, and virtually nothing is known about their vocalisations in the predation context. This thesis presents a detailed description of the form and function of the anti-predator behaviour of one species of titi monkeys, the black-fronted titi monkey (Callicebus nigrifrons), with a specific focus on their alarm call behaviour. A second aim was to determine the exact mechanisms of alarm calling behaviour, with an emphasis on production and comprehension. Data were collected from several habituated groups in the Caraça Reserve, Minas Gerais, Brazil. Results showed that, when detecting predator species, C nigrifrons produce sequences that initially contain two types of brief, high-pitched calls with distinct frequency contours. Further evidence suggested that some of these sequences are meaningful to conspecific receivers, by indicating the general predator class and location of threat. There were also indications that, within the terrestrial threats, additional information may be encoded by acoustic and compositional differences. Analyses of call order and number of calls per sequence suggested that callers may be able to convey information on both predator type and location. The black-fronted titi monkeys’ vocal system thus provides a further example of zoo-syntax, in which acoustically fixed units of a vocal repertoire are combined into higher order sequences that are meaningful to recipients. According to current definitions, this type of calling behaviour qualifies as functionally referential, by indicating general predator class, terrestrial predator type and location. As such, this is the first empirical demonstration of a sequence-based alarm call system that conveys information on both predator category and location.

A Floresta Atlântica, principalmente sua porção localizada no interior do Estado de São Paulo, encontra-se altamente fragmentada e seus remanescentes, em sua maioria, encontram-se envoltos por uma matriz essencialmente agrícola. Este estudo foi realizado no Campus "Luiz de Queiroz", Universidade de São Paulo, localizado no município de Piracicaba, Estado de São Paulo. O mesmo encontra-se inserido no perímetro urbano da cidade de Piracicaba, tendo como limite duas rodovias e o Rio Piracicaba. A paisagem da área de estudo caracteriza-se por um mosaico de pequena áreas florestais envoltas por áreas de pastagens, agricultura e florestamento com espécies exóticas. Os objetivos principais do presente estudo foram: levantamento de mamíferos não-voadores, em escala local, incluindo sua distribuição e abundância de acordo com o mosaico de ambientes resultantes do expressivo impacto causado pelo desenvolvimento humano na área. A coleta de pequenos mamíferos ocorreu durante nove meses, entre fevereiro e outubro de 2001, com um esforço de 7056 armadilhas/dia, tendo sido amostrados sete dos ambientes mais representativos do Campus(florestamento de Eucalyptus e Pinus, fragmento florestal nativo, várzea, plantio de seringueira, área de agricultura e área de pastagem). Para o registro de mamíferos de médio e grande portes foi construída uma trilha pelo Campus, que foi percorrida durante 12 meses, entre novembro de 2000 e outubro de 2001, no período da manhã e da tarde. Em todo o Campus foram registradas 16 espécies de mamíferos não-voadores, sendo dez de médio e grande portes e seis de pequeno porte, sendo a capivara (Hydrochaeris hydrochaeris) e o coati (Nasua nasua) as espécies mais abundantes. / The remaining portion of the Atlantic Forest within the State of Sao Paulo is highly fragmented and most of the remainders are wrapped up in an essentially agricultural mosaic. This study aims local surveying of non-flying mammals, including their distribution and relative abundance within the humanimpacted environments of Campus "Luiz de Queiroz", University of Sao Paulo, Piracicaba, SP, Brazil, an urbanized area bordered by two highways and the Piracicaba River. The landscape of the study area is characterized by a mosaic of small forest fragments surrounded by pastures, agriculture, and planted forests. Small mammals were captured from February to October, 2001, with an effort of 7056 traps.day -1 , sampling seven of the most representative environments of the Campus - planted Eucalyptus and Pinus forests, native forest fragments, meadow, rubber tree plantation, agriculture and pasture areas. Occurrence of medium and large frame mammals was recorded daily (morning and afternoon) from November of 2000 to October of 2001 along a trail set up to merge the studied environments. Sixteen species of non-flying mammals were recorded, ten of medium or big frames, and six of small frame. Capybara (Hydrochaeris hydrochaeris) and coati (Nasua nasua) were the most abundant species.

Chez les mammifères, IDO1, une enzyme induite dans les situations inflammatoires, joue des rôles multiples et complexes dans le cadre des réponses immunes innées et acquises. De façon intéressante, IDO1 est constitutivement exprimée par l’épithélium épididymaire où il est envisagé qu’elle participe à l’installation d’une situation d’immunotoloréance vis à vis des spermatozoïdes lesquels constituent un « challenge »immunologique pour le mâle qui les fabrique. Afin d’aborder le(les) rôle(s) joué(s) parIDO1 et ses produits d’activité (ie. les kynurénines) dans la physiologie de l’épididyme et, plus largement, dans la fonction de reproduction, le travail présenté dans ce manuscrit décrit les résultats acquis sur le modèle murin Ido1-/-en termes de phénotypes épididymaires, spermatiques ainsi qu’en terme d’impact sur la fertilité des animaux KO. Les données présentées suggèrent qu’IDO1 est effectivement un acteur immunosuppresseur dans l’épithélium épididymaire contribuant au privilège immunaccordé par ce territoire aux gamètes mâles. L’absence d’IDO1 génère au sein de l’épididyme des perturbations d’ordre inflammatoire néanmoins corrigées par diverses réponses qui préservent l’équilibre immun et fonctionnel du tissu. Ce travail met en outre en évidence que certaines kynurénines sont particulièrement représentées dans l’épididyme et au niveau des gamètes mâles où elles pourraient jouer des rôles variés. / In mammals, IDO1 is induced in inflammatory situations and plays multiple and complicated roles in the modulation of both innate and adaptative immune responses. Interestingly, IDO1 is constitutively expressed by the epididymal epithelium where it is envisaged that it participates in the set up of an immunotolerant environment in order to down-regulate auto immune-responses against spermatozoa. To decipher the roles played by IDO1 in the physiology of the epididymis and consequently in the male reproductive function, we show in this thesis report data obtained on the IDO1 knock-out mouse model. Data collected suggest that indeed IDO1 is an immunomodulatory player in the epididymis epithelium where it contributes to the immunotolerogenic context towards spermatozoa. When absent (ie. in the Ido1-/- genetic background) it specifically increases epididymal inflammation and triggers various tissue responses that aim at restoring the immune equlibrium. In addition, the work presented here shows that some kynurenines are particularly well represented in the epididymal epithelium as well as on spermatozoa where they could play important roles.

Hawk Rim represents a new mid-Miocene site in Eastern Oregon. This time period offers a rare chance to observe dramatic climatic changes, such as sudden warming trends. The site is sedimentologically and stratigraphically consistent with the Mascall Formation of the John Day Basin to the north and east of Hawk Rim. Hawk Rim preserves taxa such as canids Cynarctoides acridens and Paratomarctus temerarius, the felid Pseudaelurus skinneri, castorids Anchitheriomys and Monosaulax, tortoises and the remains of both cormorants and owls. Hawk Rim has yielded a new genus and species of mustelid. As individuals these taxa are of interest, but the real story is told by the paleoecology. The lower reaches of the section have lacustrine diatomite layers as well as preserved logs, suggesting the presence of a wet, forested ecosystem as conformed by the structure of the paleosols. Climate data allow us to make analyses of large-scale ecological trends in mid-Miocene Oregon.

This thesis deals with archiving morphological data utilizing a three dimensional coordinate system. Morphological reference points are archived via rectangular position coordinates, rectangular position vectors, and spherical position vectors. The concepts of translation trajectories, translation vectors, and relative position vectors are developed. Analysis of three dimensional coordinate data utilizing translation trajectories and translation vectors is described. In order to test the methodology developed, the method is applied to an analysis of harbor porpoise, Phocoena phocoena L., skull morphology. (Key words: morphology, ontogenetic trajectories, allometry, position coordinates, position vectors, translation trajectories, translation vectors, relative position vectors, and harbor porpoise).

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