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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Habitat fragmentation, patterns of diversity and phylogeography of small mammal species in the Albertine rift

Kaleme, Prince K. 12 1900 (has links)
Thesis (PhD) - Stellenbosch University, 2011. / ENGLISH ABSTRACT: The Albertine Rift is characterized by a heterogeneous landscape which may, at least in part, drive the exceptional biodiversity found across all taxonomic levels. Notwithstanding the biodiversity and beauty of the region, large areas are poorly understood because of political instability with the inaccessibility of most of the region as a contributing factor. The majority of studies in the Albertine Rift have focussed on charismatic mega fauna, with other taxa receiving less attention. One of the taxonomically and numerically more abundant small mammal genera is the genus Praomys, an African endemic with a wide distribution range spanning most of west, central and east Africa. Four species are typically recognized from the Albertine Rift namely P. degraaffi, P. jacksoni, P. misonnei and P. verschureni. In this study I used a combination of DNA sequence data (mitochondrial control region, mitochondrial cytochrome b and 7th intron of the nuclear ß-fibrinogen gene) as well as morphometric data (traditional and geometric) to investigate the systematics of the Praomys taxa occurring in the Albertine Rift. To allow meaningful DNA assessments and in an attempt to identify potential drivers of diversifications, other Praomys species were also included from public sequence data bases for comparisons. The main focus was on P. jacksoni (the numerically most abundant taxon; also, up to 2005, all Praomys in the Albertine Rift were mostly collected as “jacksoni”) and P. degraaffi (an Albertine Rift endemic). A surprising finding was the presence of P. mutoni; this represents a range extension for this species into the Albertine Rift. Distinct evolutionary lineages were found in both P. jacksoni (confirmed by sequence data as well as morphometrics) as well as P. degraaffi (based only on sequence data; insufficient samples precluded a full morphometric investigation). These lineages (in both P. jacksoni as well as P. degraaffi) appear to be separated along a north – south gradient; however, further investigations should confirm this. To further investigate the genetic patterns at local scales across the Albertine Rift, as well as introgression between species as revealed by sequence data, a species-specific microsatellite library was developed for P. jacksoni. Twelve polymorphic markers were identified of which nine also amplified in P. degraaffi. Introgression was confirmed between the two focal species with almost 20% of the individuals analysed being jacksoni-degraaffi hybrids. This is perhaps not so surprising given that there is considerable overlap in their ranges (between ~ 1500 m a.s.l. to 2450 m a.s.l.) as well as the relative ages of the species (the divergence time between these two species were estimated at 3.8 Mya). The presence of distinct lineages within each of these species was confirmed by microsatellite analyses (these lineages diverged approcimately at same time at ca. 3.4 Mya). As suggested by sequence and morphometric data, these lineages had a largely north – south distribution but with considerable overlap in the central Albertine Rift in the vicinity of Lake Kivu. The phylogeographic patterns obtained for both focal species were not consistent with the physical barriers such as the rivers, lakes or mountains, nor were they exclusively associated with Pleistocene phenomena such as the change of the course of the rivers or uplift; rather, the lineages predate the Pleistocene and fall firmly in the Pliocene (>3 Mya). Biogeographically, the north - south location of lineages with a centrally - located contact zone could be a result of parapatric speciation due to habitat fragmentation or past climate change, followed by secondary contact. Barcoding using genetic information provides a useful tool to identify unknown taxa, cryptic diversity or where different life stages are difficult to identify. From an invasion biology perspective, it allows for the rapid identification of problem taxa against a known data base. By adopting such a barcoding approach (senso lato), the presence of three invasive rodents was confirmed in the Democratic Republic of the Congo (DRC); these are Rattus rattus (black rat), R. norvegicus (Norway rat) and Mus musculus domesticus (house mouse). A comparison with global data available for these species revealed two possible introduction pathways namely via the shipping port at Kinshasa/Matadi (with strong links to Europe) and via the slave trade routes in the east (strong links to the Arab world and the east). Of these three taxa, only R. rattus is currently documented from the DRC although the others have received mention in the gray literature. These findings draw attention to the lack of any official policy regarding biosecurity in the DRC, and argue for the development of strict control measures to prevent further introductions. / AFRIKAANSE OPSOMMING: Die Albertine Rift word gekenmerk deur 'n heterogene landskap wat kan, ten minste gedeeltelik, die uitsonderlike biodiversiteit wat oor al die taksonomiese vlakke gevind word teweeg bring. Nieteenstaande die biodiversiteit en die skoonheid van die streek, is groot gebiede onbekend as gevolg van politieke onstabiliteit met die ontoeganklikheid van meeste van die streek as 'n bydraende faktor. Die meerderheid van studies in die Albertine Rift het gefokus op die charismatiese mega fauna, met ander taxa wat minder aandag ontvang. Een van die taksonomies en numeries meer volop klein soogdier genera is die genus Praomys, 'n Afrika endemiese groep met 'n wye verspreiding wat strek oor die grootste deel van van wes-, sentraal en oos-Afrika. Vier spesies word tipies erken van die Albertine Rift naamlik P. degraaffi, P. jacksoni, P. misonnei en P. verschureni. In hierdie studie het ek 'n kombinasie van DNA volgorde data (mitochondriale beheer streek, mitochondriale sitochroom b en 7de intron van die kern ß-fibrinogeen geen) sowel as morfometriese data (tradisioneel en meetkundig) gebruik om die sistematiek van die Praomys taxa te ondersoek. Om betekenisvolle DNA aanslae toe te laat en in 'n poging om potensiële aandrywers van diversiteit te identifiseer, is ander Praomys spesies van openbare volgorde data basisse vir vergelykings ingesluit. Die hooffokus is op P. jacksoni (die numeries volopste takson, ook, tot en met 2005 is alle Praomys in die Albertine Rift meestal as "jacksoni" versamel) en P. degraaffi ('n Albertine Rift endemiese spesie). 'n Verrassende bevinding was die teenwoordigheid van P. mutoni, dit verteenwoordig' n verspreidingsuitbreiding vir hierdie spesie in die Albertine Rift. Bepaalde evolusionêre ontwikkelingslyne was in beide P. jacksoni (bevestig deur die volgorde data sowel as morfometrie) sowel as P. degraaffi (wat slegs gebaseer is op die volgorde data, onvoldoende monsters verhinder 'n volledige morfometriese ondersoek). Hierdie lyne (in beide P. jacksoni sowel as P. degraaffi) word geskei langs 'n noord - suid gradiënt, maar verdere ondersoeke moet dit bevestig. Om die genetiese patrone op plaaslike skaal oor die Albertina Rift verder te ondersoek, sowel as introgressie tussen spesies soos geopenbaar deur die volgorde data, is 'n spesie-spesifieke mikrosatelliet biblioteek ontwikkel vir P. jacksoni. Twaalf polimorfiese merkers is geïdentifiseer waarvan nege ook amplifiseer in P. degraaffi. Introgressie is bevestig tussen die twee brandpunt spesies met byna 20% van die individue wat ontleed is as jacksoni-degraaffi basters. Dit is miskien nie so verbasend gegee dat daar aansienlike oorvleueling is in hul gebiede (tussen ~ 1500 m bo seespieel tot 2450 m bo seespieel), sowel as die relatiewe ouderdomme van die spesies (die divergensie tussen hierdie twee spesies is geskat op 3,8 Mya). Die teenwoordigheid van verskillende lyne in elk van hierdie spesies is bevestig deur mikrosatelliet ontleding (hierdie lyne het gedivergeer ongeveer 3,4 Mya). Soos voorgestel deur die DNA volgorde en morfometriese data, het hierdie lyne 'n grootliks noorde – suid verspreiding, maar met 'n aansienlike oorvleueling in die sentrale Albertine Rift in die omgewing van die Kivumeer. Die filogeografiese patrone wat vir beide die brandpunt spesies gevind is nie in ooreenstemming met die fisiese struikelblokke soos die riviere, mere of berge nie, en hou ook nie uitsluitlik verband met die Pleistoseen verskynsels soos die verandering van die loop van die riviere nie; die afstammelinge is eerder veel ouer as die Pleistoseen en val binne die Plioseen (> 3 Mya). Biogeografies, die noorde – suid plasing van die lyne met 'n sentraal geleë kontak sone kan die gevolg wees van parapatriese spesiasie te danke aan habitatfragmentasie as gevolg van verandering in die klimaat, gevolg deur 'n sekondêre kontak. Strepieskodering met behulp van genetiese inligting verskaf 'n nuttige instrument om onbekend taxa, kriptiese diversiteit of waar verskillende lewensfases moeilik is om te identifiseer, te identifiseer. Vanuit 'n indringerbiologie perspektief, maak hierdie benadering dit moontlik om vinnige identifikasies van die probleem taksa teen' n bekende data basis te bekom. Deur gebruik te maak van so 'n strepieskoderingsbenadering (senso lato), is die teenwoordigheid van drie indringende knaagdiere bevestig in die Demokratiese Republiek van die Kongo (DRK), naamlik Rattus rattus (swart rot), R. norvegicus (Noorweë rot) en Mus musculus domesticus (huis muis). 'n Vergelyking met die globale data wat beskikbaar is vir hierdie spesies het aan die lig gebring dat twee moontlike betree-roetes bestaan, naamlik via die skeepshawe by Kinshasa / Matadi (met sterk skakels na Europa), en via die slawehandel roetes in die ooste (sterk skakels na die Arabiese wêreld en die ooste) . Van hierdie drie taxa, is tans slegs R. rattus van die Demokratiese Republiek van die Kongo gedokumenteer, hoewel die ander melding ontvang in die grys literatuur. Hierdie bevindinge vestig die aandag op die gebrek aan enige amptelike beleid ten opsigte van biosekuriteit in die Demokratiese Republiek van die Kongo, en argumenteer vir die ontwikkeling van streng beheermaatreëls om verdere indringerspesies te voorkom.
2

Variação morfológica e molecular das populações de Mesoclemmys vanderhaegei (Testudines: Chelidae) / Morphological and molecular variation of the Mesoclemmys vanderhaegei populations (Testudines: Chelidae)

Souza, Rodrigo Araujo de 12 September 2014 (has links)
Mesoclemmys vanderhaegei Bour, 1973 pertence à família Chelidae, que apresenta maior riqueza de espécies de Testudines no Brasil. Apesar de não se suspeitar do monofiletismo da família, há muitas dúvidas sobre as relações entre os táxons de Chelidae, com a possibilidade de vários grupos se revelarem parafiléticos. Mesoclemmys vanderhaegei tem uma ampla distribuição no centro-sul do continente sul-americano, havendo sido estudada mais especificamente sob uma temática ecológica. Seus aspectos taxonômicos e filogenéticos, porém, ainda necessitam de uma investigação mais detalhada, visto que o grupo pode representar um complexo de espécies. O presente trabalho visa, portanto, estudar as populações de M. vanderhaegei sob um ponto de vista taxonômico e filogenético, buscando identificar e caracterizar as populações através das divergências evolutivas que venham a ser reveladas, justificando assim um eventual desmembramento da espécie. Sendo assim, as populações de M. vanderhaegei foram investigadas por meio de técnicas de morfometria tradicional, morfometria geométrica, e uma filogenia molecular foi proposta para o gênero. Para a morfometria tradicional foram analisadas medidas lineares do plastrão, carapaça e cabeça; enquanto que para a morfometria geométria foram selecionados landmarks nos vértices dos escudos do casco e na linha média dorsal e ventral de cada espécime. Para o estudo de filogenia molecular, foram sequenciados três genes nucleares (RAG-2, R35 e c-mos), e dois mitocondriais (12S e NADH) de representantes da maioria das populações da espécie, e de todas as espécies do gênero. A análise discriminante tanto para os dados de medidas lineares quanto para os de landmarks separa a população do sul da Bacia do Paraguai (próxima à localidade tipo da espécie) das demais populações brasileiras. As análises morfométricas diferenciam outras duas populações: uma população composta por espécimes da Chapada dos Guimarães (MT), região de Cuiabá e um exemplar de Bonito (MS); enquanto a outra população é representada por espécimes de São João da Ponte (MG), na Bacia do São Francisco. A topologia resultante da análise de máxima verossimilhança aponta M. vanderhaegei como um grupo polifilético, com a possibilidade de ser dividida em quatro espécies: uma com os espécimes do sul da Bacia Amazônica; outra com os espécimes de Montes Claros (MG), na Bacia do São Francisco; uma terceira com os espécimes de São João da Lagoa e do interior de São Paulo (Bacia do Paraná, sub Bacia do Tietê); além daquela formada pelos espécimes próximos à localidade tipo. Sugere-se, portanto, (1) que a distribuição de Mesoclemmys vanderhaegei seja restringida ao norte da Argentina, Paraguai, e oeste do Mato Grosso do Sul até que novos estudos venham a elucidar o quanto a espécie adentra o território brasileiro; (2) que as populações da região da Chapada dos Guimarães e do interior de Minas Gerais sejam elevadas ao nível de espécie; (3) e que se façam novos estudos para elucidar a relação das populações da Bacia do Tocantins-Araguaia e Paraná com os outros grupos do complexo.! / Mesoclemmys vanderhaegei Bour, 1973 belongs to the family Chelidae, which presents the greatest variety of species of Testudines in Brazil. In spite of theories that suggest that the family might be monophyletic, there are still areas of doubt over the relationships between the taxa that belong to the Chelidae, and the possibility that various groups might prove to be paraphyletic. Mesoclemmys vanderhaegei has a large distribution range along the central and southern regions of the South American continent, and has been most specifically studied through an ecological perspective. A more detailed investigation of its taxonomic and phylogenetic characteristics is still both relevant and necessary, since the complex might represent multiple species. The present work aims, therefore, to study the populations of M. vanderhaegei from a phylogenetic and taxonomic perspective, looking to identify and characterize the populations in accordance with the evolutionary divergences that may be observed, thus justifying the subdivision of the complex into mutiple species. With this in mind, the populations of M. vanderhaegei were investigated using techniques of traditional and geometric morphometry, and a molecular phylogeny was proposed for the genus. The traditional morphometric data accounted for linear measurements of the plastron, carapace and head whilegeometric morphometric data were chosen as landmarks on the vertices of the scutes of the shells and on the dorsal and ventral midline of each specimen. Using samples of the majority of the populations of the species, and of all the species of the genus, three nuclear (RAG-2, R35 and c-mos) and two mitochondrial genes (12S and NADH) were sequenced for the study of the molecular phylogeny. Both the discriminant analysis of the linear measurements data and that of the landmarks separate the population found in the South of the Paraguay Basin (near the type locality of the species) from other Brazilian populations. The morphometric analyses show two other distinct populations: a population composed of specimens from Chapada dos Guimarães (MT), in the region of Cuiabá and one specimen from Bonito (MS); while the other population is represented by specimens taken from São João da Lagoa (MG), in the Basin of São Francisco. The resulting tree topology of theMaximum-Likelihood analysis derived from the molecular data suggests that M. vanderhaegei should be considered a polyphyletic group, that can be divided into four species: one species represented by the specimens from the South of the Amazonian Basin; another represented by the specimens from Montes Claros (MG), in the Basin of São Francisco; a third represented by the specimens from São João da Lagoa and the interior of São Paulo (Paraná Basin, sub Basin of the river Tietê); in addition to the one formed of the specimens close to the type locality. This would suggest, therefore, (1) that the distribution of Mesoclemmys vanderhaegei is restricted to the North of Argentina, Paraguay, and the West of Mato Grosso do Sul, until further studies are made to elucidate the extent to which the species has spread into Brazilian territory; (2) that the population of the Chapada dos Guimarães region and of the interior of Minas Gerais should be elevated to the category of species; (3) and that new studies must be carried out to determine the relationship between the populations of the Basin of Tocantins-Araguaia and Paraná with the other groups of the complex.!
3

Characterization Of Taxonomically Related Some Turkish Oak (quercus L.) Species In An Isolated Stand: A Morphometric Analysis Approach

Aktas, Caner 01 June 2010 (has links) (PDF)
The genus Quercus L. is represented with more than 400 species in the world and 18 of these species are found naturally in Turkey. Although its taxonomical, phytogeographical and dendrological importance, the genus Quercus is still taxonomically one of the most problematical woody genus in Turkish flora. In this study, multivariate morphometric approach was used to analyze oak specimens collected from an isolated forest (Beynam Forest, Ankara) where Quercus pubescens Willd., Q. infectoria Olivier subsp. boissieri (Reuter) O. Schwarz and Q. macranthera Fisch. &amp / C. A. Mey. ex Hohen. subsp. syspirensis (C.Koch) Menitsky taxa are belonging to section Quercus sensu stricto (s.s.) are found. Additional oak specimens were included in the analysis for comparison. Morphometric study was based on 52 leaf characters such as, distance, angle, and area as well as counted, descriptive and calculated variables. Morphometric variables were calculated automatically by use of landmark and outline data. Random forest classification method was used to select discriminating variables and predict unidentified specimens by use of pre-identified training group. The results of the random forest variable selection procedure and the principal component analysis (PCA) showed that the morphometric variables could distinguish the specimens of Q. pubescens and Q. macranthera subsp. syspirensis mostly based on the overall leaf size and number of intercalary veins while the specimens of Q. infectoria subsp. boissieri were separated from others based on lobe and lamina base shape. Finally, micromorphological observations of abaxial lamina surface have been performed by scanning electron microscope (SEM) on selected specimens which were found useful to differentiate, particularly the specimens of Q. macranthera subsp. syspirensis and its putative hybrids from other taxa.
4

Variação geográfica do boto-de-burmeister, Phocoena spinipinnis (Burmeister, 1865) (Cetacea : Phocoenidae) nas costas Atlântica e Pacífica da América do Sul

Schiller, Daniza Marcela Montserrat Molina January 2006 (has links)
Um total de 142 crânios do boto-de-Burmeister, Phocoena spinipinnis depositados em museus e coleções cientificas da Argentina, Brasil, Chile, Peru e Uruguai foram utilizados para explorar a variação geográfica em relação ao tamanho e forma do crânio de P. spinipinnis. Ademais, foi realizada uma caracterização oceanográfica da área de distribuição do boto-de- Burmeister através de dados históricos de temperatura, salinidade e oxigênio a 0 e 50m de profundidade na costa Atlântica e Pacifica. As idades dos animais foram obtidas pelas leituras das GLGs na dentina. A idade mais alta atingida por ambos os sexos foi de 10 anos. Medições na dentina mostraram dimorfismo sexual na primeira GLG e diferenças geográficas entre botos do Peru e Atlântico. Três tipos de anomalias foram registrados nos dentes, e a linha marcadora parece estar associada ao “El Niño”. Vinte e oito caracteres métricos foram utilizados para explorar o dimorfismo sexual e crescimento. A maturidade física do crânio foi estabelecida quando o comprimento côndilo-basal atingiu 95% do comprimento total (≥266mm nos machos e ≥277mm nas fêmeas). Diferenças no tamanho e forma do crânio foram analisadas através de morfometria tradicional e geométrica. Os resultados revelaram dimorfismo sexual, sendo as fêmeas maiores do que os machos. As diferenças em tamanho e forma concentraram-se principalmente na região rostral e neurocrânio. Foi observada variação geográfica entre os botos do Atlântico, Chile e Peru. P. spinipinnis do Peru são de menor tamanho em relação a os botos do Chile e Atlântico. Botos do Chile apresentam um tamanho e forma intermediária, e os botos do Atlântico são maiores (especialmente na região orbital, altura do crânio e região rostral). A distância de Mahalanobis mostrou maior separação entre os botos do Peru e do Atlântico, e menor distância entre os exemplares do Chile e Atlântico. A morfometria geométrica explica com maior clareza as diferenças entre botos do Chile e Atlântico, especialmente nas vista ventral e lateral. A correlação entre variáveis ambientais e morfométricas através da análise de correlações canônicas e dos quadrados mínimos parciais de dois blocos sugere que as diferenças observadas no tamanho e na forma dos crânios têm uma importante influência espacial, associada à variabilidade sazonal das condições oceanográficas presentes nos dois oceanos e diretamente relacionada às três áreas oceanográfica propostas neste estudo: (1) de Paita, Peru (05°01’S, 81ºW) até o sul do Golfo de Arauco, Chile (∼39°S); (2) do sul do Golfo de Arauco até o sul do Rio da Prata (∼38°S); e (3) do Rio da Prata até Santa Catarina, Brasil (28º48’S; 49°12W). Adicionalmente, propõe-se que P. spinipinnis apresenta uma distribuição contínua desde Paita, Peru ate a bacia do Rio da Prata, Argentina, podendo alcançar águas uruguaias e brasileiras em determinadas condições oceanográficas (entrada de águas mais frias e menos salinas com direção ao norte, associadas à Convergência Subtropical) / A total of 142 skulls from Burmeister’s porpoises, Phocoena spinipinnis from museums and scientific collections from Argentina, Brazil, Chile, Peru and Uruguay were analyzed to explore the geographical variation in relation to size and shape on skulls of P. spinipinnis. In addition, an oceanographic characterization of the area of distribution of Burmeister’s porpoise by historical data of temperature, salinity and oxygen the 0 and 50m of depth on the Pacific and Atlantic coast was carried out. The age of the animals was obtained by reading the Growth Layer Group in dentine. The oldest male and female were 10 years of age. Measurements in dentine showed sexual dimorphism in the first GLG and geographic differences between porpoises from Peru and Atlantic. Three types of anomalies were recorded in teeth, and the marker lines seem to be associated to “El Niño”. Twenty-eight characters were used to explore sexual dimorphism and growth. Physical maturity of the skull was established when 95% of condylobasal length was attained (≥266mm in the males and ≥277mm in the females). Differences in size and shape of skull were analyzed by traditional and geometric morphometrics. The results revealed sexual dimorphism, being the females larger than male, and the differences in size and shape are concentrated mainly in the rostral region and neurocranium. Geographic variation between porpoises from Atlantic, Chile, and Peru was observed. P. spinipinnis from Peru are smaller compared to porpoises from Chile and Atlantic. Porpoises from Chile have an intermediate shape, and porpoises from Atlantic are larger (mainly related to orbital region, skull height and rostral region). The distance of Mahalanobis showed more separation between porpoises from Peru and Atlantic, and less distance between specimens from Chile and Atlantic. Geometric morphometrics was more useful for show differences between specimens from Chile and Atlantic, especially in the ventral and lateral views. The correlation between environmental and morphometric variables by canonical analysis and two-block partial least squares suggests that the differences observed in the size and shape of skulls would have an important spatial influence, associated to the seasonal variability of the oceanographic conditions present in the two oceans, and directly related to the three oceanographic areas proposed in this study: (1) from Paita, Peru (05°01’S, 81ºW) to south of Arauco Gulf, Chile (∼39°S); (2) from south of Arauco Gulf to south of La Plata River, Argentina (∼38°S); and (3) from La Plata River to Santa Catarina, Brazil (28º48’S; 49°12W). In addition, it is proposed that P. spinipinnis presents a continuous distribution from Paita, Peru to La Plata River basin, Argentina, being able to reach Uruguayan and Brazilian waters under certain oceanographic conditions (intrusion of colder and less saline waters toward the north associated with the Subtropical Convergence).
5

Variação geográfica do boto-de-burmeister, Phocoena spinipinnis (Burmeister, 1865) (Cetacea : Phocoenidae) nas costas Atlântica e Pacífica da América do Sul

Schiller, Daniza Marcela Montserrat Molina January 2006 (has links)
Um total de 142 crânios do boto-de-Burmeister, Phocoena spinipinnis depositados em museus e coleções cientificas da Argentina, Brasil, Chile, Peru e Uruguai foram utilizados para explorar a variação geográfica em relação ao tamanho e forma do crânio de P. spinipinnis. Ademais, foi realizada uma caracterização oceanográfica da área de distribuição do boto-de- Burmeister através de dados históricos de temperatura, salinidade e oxigênio a 0 e 50m de profundidade na costa Atlântica e Pacifica. As idades dos animais foram obtidas pelas leituras das GLGs na dentina. A idade mais alta atingida por ambos os sexos foi de 10 anos. Medições na dentina mostraram dimorfismo sexual na primeira GLG e diferenças geográficas entre botos do Peru e Atlântico. Três tipos de anomalias foram registrados nos dentes, e a linha marcadora parece estar associada ao “El Niño”. Vinte e oito caracteres métricos foram utilizados para explorar o dimorfismo sexual e crescimento. A maturidade física do crânio foi estabelecida quando o comprimento côndilo-basal atingiu 95% do comprimento total (≥266mm nos machos e ≥277mm nas fêmeas). Diferenças no tamanho e forma do crânio foram analisadas através de morfometria tradicional e geométrica. Os resultados revelaram dimorfismo sexual, sendo as fêmeas maiores do que os machos. As diferenças em tamanho e forma concentraram-se principalmente na região rostral e neurocrânio. Foi observada variação geográfica entre os botos do Atlântico, Chile e Peru. P. spinipinnis do Peru são de menor tamanho em relação a os botos do Chile e Atlântico. Botos do Chile apresentam um tamanho e forma intermediária, e os botos do Atlântico são maiores (especialmente na região orbital, altura do crânio e região rostral). A distância de Mahalanobis mostrou maior separação entre os botos do Peru e do Atlântico, e menor distância entre os exemplares do Chile e Atlântico. A morfometria geométrica explica com maior clareza as diferenças entre botos do Chile e Atlântico, especialmente nas vista ventral e lateral. A correlação entre variáveis ambientais e morfométricas através da análise de correlações canônicas e dos quadrados mínimos parciais de dois blocos sugere que as diferenças observadas no tamanho e na forma dos crânios têm uma importante influência espacial, associada à variabilidade sazonal das condições oceanográficas presentes nos dois oceanos e diretamente relacionada às três áreas oceanográfica propostas neste estudo: (1) de Paita, Peru (05°01’S, 81ºW) até o sul do Golfo de Arauco, Chile (∼39°S); (2) do sul do Golfo de Arauco até o sul do Rio da Prata (∼38°S); e (3) do Rio da Prata até Santa Catarina, Brasil (28º48’S; 49°12W). Adicionalmente, propõe-se que P. spinipinnis apresenta uma distribuição contínua desde Paita, Peru ate a bacia do Rio da Prata, Argentina, podendo alcançar águas uruguaias e brasileiras em determinadas condições oceanográficas (entrada de águas mais frias e menos salinas com direção ao norte, associadas à Convergência Subtropical) / A total of 142 skulls from Burmeister’s porpoises, Phocoena spinipinnis from museums and scientific collections from Argentina, Brazil, Chile, Peru and Uruguay were analyzed to explore the geographical variation in relation to size and shape on skulls of P. spinipinnis. In addition, an oceanographic characterization of the area of distribution of Burmeister’s porpoise by historical data of temperature, salinity and oxygen the 0 and 50m of depth on the Pacific and Atlantic coast was carried out. The age of the animals was obtained by reading the Growth Layer Group in dentine. The oldest male and female were 10 years of age. Measurements in dentine showed sexual dimorphism in the first GLG and geographic differences between porpoises from Peru and Atlantic. Three types of anomalies were recorded in teeth, and the marker lines seem to be associated to “El Niño”. Twenty-eight characters were used to explore sexual dimorphism and growth. Physical maturity of the skull was established when 95% of condylobasal length was attained (≥266mm in the males and ≥277mm in the females). Differences in size and shape of skull were analyzed by traditional and geometric morphometrics. The results revealed sexual dimorphism, being the females larger than male, and the differences in size and shape are concentrated mainly in the rostral region and neurocranium. Geographic variation between porpoises from Atlantic, Chile, and Peru was observed. P. spinipinnis from Peru are smaller compared to porpoises from Chile and Atlantic. Porpoises from Chile have an intermediate shape, and porpoises from Atlantic are larger (mainly related to orbital region, skull height and rostral region). The distance of Mahalanobis showed more separation between porpoises from Peru and Atlantic, and less distance between specimens from Chile and Atlantic. Geometric morphometrics was more useful for show differences between specimens from Chile and Atlantic, especially in the ventral and lateral views. The correlation between environmental and morphometric variables by canonical analysis and two-block partial least squares suggests that the differences observed in the size and shape of skulls would have an important spatial influence, associated to the seasonal variability of the oceanographic conditions present in the two oceans, and directly related to the three oceanographic areas proposed in this study: (1) from Paita, Peru (05°01’S, 81ºW) to south of Arauco Gulf, Chile (∼39°S); (2) from south of Arauco Gulf to south of La Plata River, Argentina (∼38°S); and (3) from La Plata River to Santa Catarina, Brazil (28º48’S; 49°12W). In addition, it is proposed that P. spinipinnis presents a continuous distribution from Paita, Peru to La Plata River basin, Argentina, being able to reach Uruguayan and Brazilian waters under certain oceanographic conditions (intrusion of colder and less saline waters toward the north associated with the Subtropical Convergence).
6

Variação geográfica do boto-de-burmeister, Phocoena spinipinnis (Burmeister, 1865) (Cetacea : Phocoenidae) nas costas Atlântica e Pacífica da América do Sul

Schiller, Daniza Marcela Montserrat Molina January 2006 (has links)
Um total de 142 crânios do boto-de-Burmeister, Phocoena spinipinnis depositados em museus e coleções cientificas da Argentina, Brasil, Chile, Peru e Uruguai foram utilizados para explorar a variação geográfica em relação ao tamanho e forma do crânio de P. spinipinnis. Ademais, foi realizada uma caracterização oceanográfica da área de distribuição do boto-de- Burmeister através de dados históricos de temperatura, salinidade e oxigênio a 0 e 50m de profundidade na costa Atlântica e Pacifica. As idades dos animais foram obtidas pelas leituras das GLGs na dentina. A idade mais alta atingida por ambos os sexos foi de 10 anos. Medições na dentina mostraram dimorfismo sexual na primeira GLG e diferenças geográficas entre botos do Peru e Atlântico. Três tipos de anomalias foram registrados nos dentes, e a linha marcadora parece estar associada ao “El Niño”. Vinte e oito caracteres métricos foram utilizados para explorar o dimorfismo sexual e crescimento. A maturidade física do crânio foi estabelecida quando o comprimento côndilo-basal atingiu 95% do comprimento total (≥266mm nos machos e ≥277mm nas fêmeas). Diferenças no tamanho e forma do crânio foram analisadas através de morfometria tradicional e geométrica. Os resultados revelaram dimorfismo sexual, sendo as fêmeas maiores do que os machos. As diferenças em tamanho e forma concentraram-se principalmente na região rostral e neurocrânio. Foi observada variação geográfica entre os botos do Atlântico, Chile e Peru. P. spinipinnis do Peru são de menor tamanho em relação a os botos do Chile e Atlântico. Botos do Chile apresentam um tamanho e forma intermediária, e os botos do Atlântico são maiores (especialmente na região orbital, altura do crânio e região rostral). A distância de Mahalanobis mostrou maior separação entre os botos do Peru e do Atlântico, e menor distância entre os exemplares do Chile e Atlântico. A morfometria geométrica explica com maior clareza as diferenças entre botos do Chile e Atlântico, especialmente nas vista ventral e lateral. A correlação entre variáveis ambientais e morfométricas através da análise de correlações canônicas e dos quadrados mínimos parciais de dois blocos sugere que as diferenças observadas no tamanho e na forma dos crânios têm uma importante influência espacial, associada à variabilidade sazonal das condições oceanográficas presentes nos dois oceanos e diretamente relacionada às três áreas oceanográfica propostas neste estudo: (1) de Paita, Peru (05°01’S, 81ºW) até o sul do Golfo de Arauco, Chile (∼39°S); (2) do sul do Golfo de Arauco até o sul do Rio da Prata (∼38°S); e (3) do Rio da Prata até Santa Catarina, Brasil (28º48’S; 49°12W). Adicionalmente, propõe-se que P. spinipinnis apresenta uma distribuição contínua desde Paita, Peru ate a bacia do Rio da Prata, Argentina, podendo alcançar águas uruguaias e brasileiras em determinadas condições oceanográficas (entrada de águas mais frias e menos salinas com direção ao norte, associadas à Convergência Subtropical) / A total of 142 skulls from Burmeister’s porpoises, Phocoena spinipinnis from museums and scientific collections from Argentina, Brazil, Chile, Peru and Uruguay were analyzed to explore the geographical variation in relation to size and shape on skulls of P. spinipinnis. In addition, an oceanographic characterization of the area of distribution of Burmeister’s porpoise by historical data of temperature, salinity and oxygen the 0 and 50m of depth on the Pacific and Atlantic coast was carried out. The age of the animals was obtained by reading the Growth Layer Group in dentine. The oldest male and female were 10 years of age. Measurements in dentine showed sexual dimorphism in the first GLG and geographic differences between porpoises from Peru and Atlantic. Three types of anomalies were recorded in teeth, and the marker lines seem to be associated to “El Niño”. Twenty-eight characters were used to explore sexual dimorphism and growth. Physical maturity of the skull was established when 95% of condylobasal length was attained (≥266mm in the males and ≥277mm in the females). Differences in size and shape of skull were analyzed by traditional and geometric morphometrics. The results revealed sexual dimorphism, being the females larger than male, and the differences in size and shape are concentrated mainly in the rostral region and neurocranium. Geographic variation between porpoises from Atlantic, Chile, and Peru was observed. P. spinipinnis from Peru are smaller compared to porpoises from Chile and Atlantic. Porpoises from Chile have an intermediate shape, and porpoises from Atlantic are larger (mainly related to orbital region, skull height and rostral region). The distance of Mahalanobis showed more separation between porpoises from Peru and Atlantic, and less distance between specimens from Chile and Atlantic. Geometric morphometrics was more useful for show differences between specimens from Chile and Atlantic, especially in the ventral and lateral views. The correlation between environmental and morphometric variables by canonical analysis and two-block partial least squares suggests that the differences observed in the size and shape of skulls would have an important spatial influence, associated to the seasonal variability of the oceanographic conditions present in the two oceans, and directly related to the three oceanographic areas proposed in this study: (1) from Paita, Peru (05°01’S, 81ºW) to south of Arauco Gulf, Chile (∼39°S); (2) from south of Arauco Gulf to south of La Plata River, Argentina (∼38°S); and (3) from La Plata River to Santa Catarina, Brazil (28º48’S; 49°12W). In addition, it is proposed that P. spinipinnis presents a continuous distribution from Paita, Peru to La Plata River basin, Argentina, being able to reach Uruguayan and Brazilian waters under certain oceanographic conditions (intrusion of colder and less saline waters toward the north associated with the Subtropical Convergence).
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Evolution et diversité de la forme du cochon entre l'âge du Fer et la période moderne en Gaule et en France. Régionalisme, acquisitions zootechniques et implications historiques. / Morphological changes in domestic pig between the Iron Age and modern times in Gaul and France : Regionalisms, zootechnical acquisitions and historical implications

Duval, Colin 11 September 2015 (has links)
Cette étude archéozoologique porte sur les variations morphologiques de différents éléments du squelette porcin (Sus scrofa domesticus) et s’appuie sur deux présupposés majeurs : (1) les changements morphologiques de l’animal sont le reflet des évolutions du contexte socio-économique ; (2) il existe une grande diversité des formes porcines, conditionnée par différents facteurs d’influence (environnement, stratégies agropastorales, habitudes culturelles, etc.). L’analyse menée, sur la base de tels postulats, tend à mesurer puis décrire ces changements et cette diversité pour tenter d’en comprendre l’origine et les mécanismes de progression. Pour cela il a fallu observer les restes dentaires et osseux de plus de 600 sites archéologiques, situés sur les territoires gaulois, français et italien, datés de La Tène moyenne à la période moderne, à l’aide de différentes méthodes de morphométrie géométrique et traditionnelle. De cette manière, il a été possible de constituer un solide référentiel ostéométrique pour le porc et d’atteindre ici une meilleure compréhension des pratiques d’élevage aux périodes gauloise, romaine et médiévale / This archaeozoological study investigates morphological variations in different skeletal parts of the pig (Sus scrofa domesticus) according to two main assumptions: (1) the morphological changes of the animal reflect socio-economic changes; (2) there is a great diversity of pig’s forms, driven by different factors (environment, agropastoral strategies, cultural habits, etc.). Our analysis, based on these assumptions, tends to quantify and describe these changes and this diversification to try to understand their origin and mechanisms. For this we have observed the dental and skeletal remains of more than 600 archaeological sites, located on the Gallic, French and Italian territories, dated from La Tène moyenne to the modern period, using different methods of geometric and traditional morphometrics. In this way, we were able to build a strong osteometric framework for pigs and get new clues to a better understanding of farming practices for Gallic, Roman and medieval periods

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