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Morphological variation of Cameroonian sunbirds
Bovšková, Denisa ; Hořák, David (advisor) ; Chmelová, Eliška (referee)
5 Abstract Morphological traits give information about the adaptations of the studied species, the resources, which it uses, and they can generally tell us about the use of ecological space. Intraspecific morphological variability reflects various adaptations of local populations thus variability reflect different way of life. The subject of this thesis is an ecologically interesting group of specialized tropical songbirds - Sunbirds (Nectarinidae). The taxon exhibits number of adaptations to specific food collecting a combination of nectarivory and insect hunting. I focused here on the intraspecific variability of three species (Cyanomitra oritis, Cinnyris reichenowi and C. bouwieri) living in different habitats in Cameroon. The aim of this work was to find out in what morphological characters are this species sexually dimorphic. Furthermore, if their populations living in remote locations differ? Finally, if all studied species show similar trend of intraspecific variability of the traits, which could have common ecological causes. The following traits were measured: wing and tail feather length, beak dimensions, total body weight and other characters. The analysis is based on field data collected between 2003 and 2015 and museum collections. Overall, we collect information about ca. 1200 individuals for...
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Sex classification using external and internal morphology of frontal bone: application in forensic science and bioarcheology
Čechová, Markéta ; Velemínská, Jana (advisor) ; Bigoni, Lucie (referee)
This master's work was focused on the assessment of sexual dimorphism of external and internal morphology of frontal bone. Sexual diagnosis based on external surface of frontal bones and volume and surface of frontal sinuses was carried out using geometric morphometrics methods. Our approach used anonimized CT scans of 103 skulls from recent Czech population, from which 3D models of frontal bones and frontal sinuses were created. At first the analysis was aimed at studying form and shape of external surface of frontal bone. Our methodology is based on the work of Musilová et al. (2016) that estimates sex using exocranial surface of the entire skull. We analyzed variability and tested differences in males and females frontal bones. The main target of this work was sex classification. The highest success rate acquired 86,41 % with the first 20 main components of form. The following part of this study was focused on sex estimation using the methodology developed by Bulut et al. (2016), which was applied in Turkish population. This method classified Czech males and females with accuracy 70,87 %. In order to complete sex determination based on the frontal bone we also used classification of the radius of the frontal bone curvature with success rate of 77,66 %. The attention was also paid to studying...
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Specifics of female locomotion from ecological and evolutionary perspective
Matějovská, Zuzana ; Hora, Martin (advisor) ; Brůžek, Jaroslav (referee)
This thesis will introduce the specifics of female locomotion, describe the level of morphological sexual dimorphism, and determine their effects on human locomotion. First of all, the thesis focuses on human sexual dimorphism in morphology and compares it with sexual dimorphism in primates. It focuses primarily on body size and proportions, lower limb length, and the pelvis. Additionally, the thesis analyses how sexual dimorphism explains the female costs of locomotion, optimal speed, and the differences in locomotion during pregnancy, infant carrying, and load carrying. Finally, the thesis analyses obstetrical dilemma hypothesis, which posits that the shape of the human female pelvis reflects an evolutionary trade-off between two competing demands, childbirth and bipedal locomotion. In light of new evidence, we concluded that human childbirth may not be limited by bipedalism as posited by the original hypothesis. Key words: sexual dimorphism, optimal walking speed, cost of transport, pregnancy, obstetrical dilemma, transport
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Morphological changes of adult human face during aging
Čiháková, Lucie ; Velemínská, Jana (advisor) ; Blažek, Vladimír (referee)
Processes of biological changes of organism over time distinctly manifest themselves in a face morphology. The present study age changes are observed as shape and size changes of transversal dates of surface 3D virtual models of faces of 443 women and men (22-88 years old) devided into six age groups in decade. Differences in faces among each age group with respect to the sex were investigated and a sexual dimorphism and its gradual progress with the age using methods of geometric morphometrics (coherent point drift - dense correspondence algorithm, principal component analysis, per vertex t-test, shell-to-shell deviation). A significant difference among age categories was observedd both in shape as well as in form of the face. The faces of women and men were becoming wider with age and convexity was decreasing at the same time. A decline of the whole forehead and of the profile of the men's nose was observed, whereas the women's foreheadwas getting bevel due to the decline of the top part and a profile of the nose wasn't changed with the age. On contrary, the men's chin was unvarying with the age, while the women's chin was sliding out foward. There was observed a distinct decline in the front part of a upper jaw with the both sex. It was found out that after the seventh life decade the face gets...
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Changes of the facial skeleton in Central Europe during the last 1200 years
Bejdová, Šárka
The objective of the Dissertation was to describe, quantify and interpret to which degree the shape and size of the facial skeleton of people living in the territory of today's Czech Republic in the period from the Early Middle Ages to the present day, i.e. in the course of the approx. last 1200 years, have changed. In this time period, morphological differences between populations, changes in the sexual dimorphism, modularity and allometry of the facial skeleton were examined. The evaluation was based on CT-images of skulls from three historical populations, specifically from the Early Middle Ages, High Middle Ages and the early modern period. The current population was represented by CT-images of living people. We studied the facial skeletons of a total of 329 individuals, of which 183 were men and 146 women. The CT- images were used as a base for the creation of virtual 3D surface models. The facial skeleton was divided into three morphological units, which were further examined. These were the skeleton of the upper face, lower jaw and palate. The statistical processing was carried out applying methods of geometric morphometrics allowing the separate studying of the shape and size variability of the examined units. When comparing the size and shape differences between studied populations it is...
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Secondary sexual traits and ageing
Novotná, Kateřina ; Tomášek, Oldřich (advisor) ; Svobodová, Jana (referee)
Sexual selection is a key evolutionary mechanism that is based on differential reproductive success among individuals. Sexual selection drives evolution of sexual dimorphism and secondary sexual traits. These traits are often of ornamental character and may function as indicators of individual quality and viability in mate-choice. Ornamental traits may signal viability in two ways: either directly, when their expression reflects body condition and ornament predicts the probability of future survival; or indirectly, if their expression is age-dependent and intense ornament express only individuals that proved the ability to survive to old age. Ornament expression may also decline in old age, however, as a result of negative effect of senescence. The aim of my thesis was to assess, whether, and which, ornaments signal individual age and survival in free-ranging vertebrates with determinate growth and whether is ornament expression affected by senescence.
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Sexually dimorphic signs of human face within the life history theory
Klusáčková, Tereza ; Flegr, Jaroslav (advisor) ; Třebický, Vít (referee)
Tereza Klusáčková: Sexually dimorphic signs of human face within the life history theory Charles University in Prague, Faculty of Natural Science, Department of Philosophy and History of Science Bachelor's thesis, pages 39, 2014 Sexually dimorphic signs play a role in a mate choice. To produce quality offsprings it is necessary to choose an individual with our preffered attractive signs which reveal good genetic material of their bearer as a partner. Presented research explains a concept of the life-history theory and also the sexual selection and its theories. A key part of it is focused on a brief anatomical description of superficial structures of human face with an emphasis on masculine and feminine appearance and dedicates to thein changes during an ontogeny. It generally defines an attractiveness, examine preferences of the opposite sex for masculine and feminine characteristics and describes changes of female appearance and preferences during the menstrual cycle. This thesis deals with topics of symmetry and averageness, which refer to good state of health and high-quality genetical basis of an individual. Marginally deals with heterozygosity and studies exploring the effect of MHC genes on the perception of attractiveness. Key words: human face, life history theory, sexual selection, sexual...
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Shape variability of proximal and distal human tibia.
Brzobohatá, Hana ; Velemínská, Jana (advisor) ; Beňuš, Radoslav (referee) ; Macholán, Miloš (referee)
The aim of this study was to detect and describe the trends in shape variability of proximal and distal human tibia related to sex, age, social status and time period. The variability of its shape and form was analysed first in an early medieval sample, then in two modern populations, an early 20th century sample and the contemporary Czech population. Finally, data from the whole studied time span were analysed. The initial raw data were acquired by optical scanning and computed tomography (CT) scanning of the lower limbs; the three-dimensional bone surfaces of the contemporary tibias were segmented from the clinical CT scan sequences. Geometric morphometrics and multivariate statistical methods were applied to study the variations in shape and form quantitatively. Proximal and distal tibias were evaluated independently, and the potential influence of sex, age at death and time period were investigated. In the early medieval population, we also explored the relationship between tibial morphology and presumed social status derived from the respective grave location within the settlement. Because traditional morphometric analysis revealed statistically significant sex differences in the parameters of both tibial extremities (e.g., Steyn and Işcan, 1997; Šlaus et al., 2013), we thus assumed the...
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Shape variability of proximal and distal human tibia.
Brzobohatá, Hana
The aim of this study was to detect and describe the trends in shape variability of proximal and distal human tibia related to sex, age, social status and time period. The variability of its shape and form was analysed first in an early medieval sample, then in two modern populations, an early 20th century sample and the contemporary Czech population. Finally, data from the whole studied time span were analysed. The initial raw data were acquired by optical scanning and computed tomography (CT) scanning of the lower limbs; the three-dimensional bone surfaces of the contemporary tibias were segmented from the clinical CT scan sequences. Geometric morphometrics and multivariate statistical methods were applied to study the variations in shape and form quantitatively. Proximal and distal tibias were evaluated independently, and the potential influence of sex, age at death and time period were investigated. In the early medieval population, we also explored the relationship between tibial morphology and presumed social status derived from the respective grave location within the settlement. Because traditional morphometric analysis revealed statistically significant sex differences in the parameters of both tibial extremities (e.g., Steyn and Işcan, 1997; Šlaus et al., 2013), we thus assumed the...
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