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Evolution of human socio-cultural and ecological traits: a phylogenetic (supertree) approach / Evolution of human socio-cultural and ecological traits: a phylogenetic (supertree) approachDUDA, Pavel January 2011 (has links)
Human species display complex intraspecies population structure and unparalleled behavioral and cultural diversity. In order to elucidate human population history and pattern of evolutionary change of socio-cultural and ecological traits, the first composite phylogenetic tree of 574 human populations (ethno-linguistic groups) was created on the basis of 129 recently published phylogenetic hypotheses based on genomic, genetic and linguistic data, utilizing supertree method matrix representation with parsimony. Subsequently, 56 selected socio-cultural and ecological characters based on ethnographic cross-cultural data were optimized on topology of obtained supertrees in order to reconstruct patterns of evolutionary change and states present in ancestral populations. The results are discussed in the light of recent studies of human phylogeography and cultural phylogenetic studies.
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Effect of ascertainment bias on calculations of sex-biased admixture in Southern AfricaÁsmundsdóttir, Ragnheidur Diljá January 2021 (has links)
Southern African populations harbour great genetic diversity enhanced by population migration to the area in the last two millennia. Africa is perhaps the least studied continent in regards to population genetics and is often underrepresented in global studies. Studying sex-biased admixture in admixed populations is a great tool to understand population demographic history as well as sex-biased admixture from past events. Various studies on sex-biased admixture in Southern Africa have shown male sex-biased admixture from the incoming Bantu-speaking populations. One study by Hollfelder (2018) shows female Bantu-speaking sex-biased admixture. Here I will try to determine if ascertainment bias is the cause of the unexpected results in Hollfelder (2018). I will do this by comparing the original results, genotyped using the Illumina Omni 2.5M Array, to overlapping SNPs in two different arrays, the Affymetrix Human Origin Array and the Infinium H3Africa Consortium Array. Additionally, I will use whole genome data containing same individuals and individuals from similar populations to form a hypothesis on how the sex-biased admixture should look like without ascertainment. Then extracting variants from the whole genome data to two array SNP panels, the Illumina 2.5M Array and the Infinium H3Africa Consortium Array. For both parts in my project a method by Goldberg and Rosenberg (2015) will be used to calculate female and male contribution from admixture proportions of the X-chromosome and the autosomes estimated using the software ADMIXTURE. The results obtained could not determine if ascertainment bias was the sole factor skewing the results. The overlap with the Affymetrix Human Origin Array showed results closest to expected results based on previous studies, suggesting that ascertainment bias likely affects the results. The results attained using the whole genome indicated that the genotype calls of individuals present in both parts of the study did not fully match and that was confirmed using a principal component analysis. Unfortunatly the data used and analytical limitations in this project did not yield answers to how ascertainment bias affects calculations on sex-biased admixture. The X-chromosome is difficult to work with, especially when using data from multiple publications, as there is no standard common best-practice pipeline available on how to process the data leading to different data sets having been treated differently, which possibly affects downstream analysis when combining data sets.
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The influence of posture and brain size on foramen magnum position in batsRuth, Aidan Alifair 05 April 2010 (has links)
No description available.
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An Australopithecus afarensis Infant First Metatarsal from Hadar, EthiopiaHillenbrand, Heather A. 23 April 2009 (has links)
No description available.
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Artificial ape man: How technology created humansTaylor, Timothy F. January 2010 (has links)
No
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The Artificial Ape: How technology changed the course of human evolution.Taylor, Timothy F. January 2010 (has links)
No / A breakthrough theory that tools and technology are the real drivers of human evolution. Although humans are one of the great apes, along with chimpanzees, gorillas, and orangutans, we are remarkably different from them. Unlike our cousins who subsist on raw food, spend their days and nights outdoors, and wear a thick coat of hair, humans are entirely dependent on artificial things, such as clothing, shelter, and the use of tools, and would die in nature without them. Yet, despite our status as the weakest ape, we are the masters of this planet. Given these inherent deficits, how did humans come out on top?
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Posthumanity's manifest destiny : NASA, its contradictory image and promises, and popular cultureBrown, Melanie Ann Rosen 01 January 2004 (has links)
No description available.
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The role of the human nasal cavity in patterns of craniofacial covariation and integrationLindal, Joshua 18 January 2016 (has links)
Climate has a selective influence on nasal cavity morphology. Due to the constraints of cranial integration, naturally selected changes in one structure necessitate changes in others in order to maintain structural and functional cohesion. The relationships between climate and skull/nasal cavity morphology have been explored, but the integrative role of nasal variability within the skull as a whole has not. This thesis presents two hypotheses: 1) patterns of craniofacial integration observed in 2D can be reproduced using 3D geometric morphometric techniques; 2) the nasal cavity exhibits a higher level of covariation with the lateral cranial base than with other parts of the skull, since differences in nasal morphology and basicranial breadth have both been linked to climatic variables. The results support the former hypothesis, but not the latter; covariation observed between the nasal cavity and other cranial modules may suggest that these relationships are characterized by a unique integrative relationship. / February 2016
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Genetic Regulation of Human Brain Size EvolutionBoyd, Jonathan Lomax January 2014 (has links)
<p>The neocortex expanded spectacularly during human origins. That expansion is thought to form the foundation for our cognitive faculties underlying abstract reasoning and socialization. The human neocortex differs from that of other great apes in several notable regards including altered cell cycle, prolonged corticogenesis, and massively increased size. However, despite decades of effort, little progress has been made in uncovering the genetic contributions that underlie these differences that distinguish our species from closely related primate, such as chimpanzees. A subset of highly conserved non-coding regions that show rapid sequence changes along the human lineage are candidate loci for the development and evolution of uniquely human traits. Several studies have identified human-accelerated enhancers, but none have linked an expression difference to a organismal traits, such as brain sizes. Here we report the discovery of a human-accelerated regulatory enhancer (HARE5) near the Wnt receptor FRIZZLED-8 (FZD8). Using a variety of approaches, we demonstrate dramatic differences in human and chimpanzee HARE5 activity, with human HARE5 driving significantly strong expression. We show that HARE5 likely regulates FZD8 and that expression differences influence cell cycle kinetics, cortical layers, and brain size. At present, this would provide the first evidence of a human-chimpanzee genetic difference influencing the evolution of brain size.</p> / Dissertation
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Functional Morphology of the Distal Forelimb and the Evolution of Tool Use in HumansLove, Sarah 14 December 2016 (has links)
Previous research on the biomechanics of tool use has focused heavily on traits correlated with locomotion, tool manufacturing, and habitual tool use. Features like the breadth of the metacarpals, relative length of the thumb, styloid process of the third metacarpal, and the breadth of the apical tufts are skeletal features associated with the use and development of stone tools. However, there are many traits of the distal forelimb that may also be correlated directly with the development and use of tools. The purpose of this research is to analyze morphological features of the hands and compare them to features of the arm in humans, fossil Homo and the great apes to understand how the hominin distal arm functions as a mosaic in response to the use of stone tools. The results indicate a separation between tool-users and non-tool users when all distal forelimb dimensions are examined. Omo 40-19 falls closer to non-tool users when univariate plots of ulna length and breadth are examined. Ratios of hand measurements to radius length are better at polarizing the tool-users from non-tool users than are hand dimensions to ulna length ratios. These results highlight the role of the radius in stabilizing the hand during stone tool production.
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