Archaeological considerations of mobility have primarily focused on the differences in and among the kinds or degrees of mobility itself, rather than addressing the underlying issue of why human settlement patterns were or are mobile. The focus of this study is to address such questions within Darwinian evolutionary theory. Using the concepts of bet-hedging, as used in biology, and waste, as used in archaeology, it is argued that mobility was selectively favored for its population limiting properties. Relative changes in the numbers of projectile points in each assigned class, ordered chronologically by seriation, were taken to indicate relative population change over time. The results of this study suggest, primarily, that rapid, drastic population growth did not occur until the abandonment of mobility in the Gulf Formational period. This result supports the expectations of the hypothesis that was tested and indicates that in this instance mobility is a bet-hedging behavior.

This thesis includes three studies. The first study examined how reductions in light availability and changes in soil chemistry that occur as conifers establish in aspen stands, differentially affects the regeneration success of aspen and conifers. We found that aspen were more sensitive to changes in light and soil then subalpine fir. For aspen, reduced light and conifer influenced soils significantly reduced height, biomass, photosynthesis and the production of secondary defense compounds. Subalpine fir seedlings were significantly reduced in photosynthesis, biomass and R:S under lower light conditions but showed no differences in physiology or growth when grown on the contrasting soil types. Subalpine fir seedlings were significantly reduced in photosynthesis, biomass and root:shoot ratio under lower light conditions but showed no differences in physiology or growth when grown on the contrasting soil types. Results from this study suggest that reduction in light and changes in soil chemistry associated with conifer succession place constraints on aspen growth and defense capacity, which may contribute to losses in aspen cover under longer disturbance return intervals. The second study looked at regeneration dynamics of aspen and conifers as forest stands transition from canopy gaps to aspen dominated canopies to conifer dominated canopies. We found that as overstory conifer density increases, aspen decrease in density, basal area, and seedling establishment. Conifers were shown to establish closer to aspen as the canopy increased in conifer density. As this proximity relationship extended into the canopy there is increased mortality in both aspen and subalpine fir, suggesting both facilitation and competition. Our third study looked at the physiological effects of smoke exposure on growth and primary and secondary metabolic responses of deciduous and conifer tree species. Twenty minutes of smoke exposure resulted in a greater than 50% reduction in photosynthetic capacity in five of the six species we examined. Impairment of photosynthesis in response to smoke was a function of reductions in stomatal conductance and biochemical limitations. In general, deciduous species showed greater sensitivity than conifer species. Smoke had no significant affect on growth or secondary defense compound production in any of the tree species examined.

Research has shown that by 7-months of age infants demonstrate recognition of emotion by successfully matching faces and voices based on affect in an intermodal matching procedure. It is often assumed that once an ability is present the development of that ability has "ceased." Therefore, no research has examined if and how the ability to match faces and voices based on affect develops after the first 7-months. This study examined how the ability to match faces and voices based on affect changes from 7- to 12-months. Looking at infant's proportion of total looking time (PTLT) results showed that, consistent with previous research, 7-month-old infants looked significantly longer at the affectively congruent facial expression. However, 12-month- olds showed no matching of faces and voices. Further analyses showed that 7-month-olds also increased their looking to facial expressions while being presented with the affectively congruent vocal expression. Once again, 12-month-olds failed to show significant matching. That 7-month- olds were able to demonstrate matching while 12-month-olds failed to do so is possibly a result of 12-month-olds attending to other information. More research is needed to better understand how infants' recognition of affect and overall perceptual abilities change as they develop.

The mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway appears to be the primary regulator of protein synthesis and growth. While resistance exercise paradigms are often divided into hypertrophy (HYP) and strength (STR) protocols, it is unknown whether these protocols differentially stimulate mTORC1 signaling. The purpose of this study was to examine mTORC1 signaling in conjunction with circulating hormone concentrations following a typical lower-body HYP and STR resistance exercise protocol. Ten resistance-trained men (24.7±3.4y; 90.1±11.3kg; 176.0±4.9cm) performed each resistance exercise protocol in a random, counterbalanced order. Blood samples were obtained at baseline (BL), immediately (IP), 30 minutes (30P), 1 hour (1H), 2 hours (2H), and 5 hours (5H) post-exercise. Fine needle muscle biopsies were completed at BL, 1H, and 5H. Electromyography of the vastus lateralis was also recorded during each protocol. HYP and STR produced a similar magnitude of muscle activation across sets. Myoglobin and lactate dehydrogenase concentrations were significantly greater following STR compared to HYP (p=0.01-0.02), whereas the lactate response was significantly higher following HYP compared to STR (p=0.003). The GH, cortisol, and insulin responses were significantly greater following HYP compared to STR (p=0.0001-0.04). No significant differences between protocols were observed for the IGF-1 or testosterone response. Intramuscular anabolic signaling analysis revealed a significantly greater (p=0.03) phosphorylation of IGF-1 receptor at 1H following HYP compared to STR. Phosphorylation status of all other signaling proteins including mTOR (mammalian target of rapamycin), p70S6k (ribosomal S6 kinase 1), and RPS6 (ribosomal protein S6) were not significantly different between trials. Despite significant differences in markers of muscle damage and the endocrine response following STR and HYP, both protocols appeared to elicit similar mTORC1 activation in resistance-trained men.

Tracking multiple targets with uncertain target dynamics is a difficult problem, especially with nonlinear state and/or measurement equations. Random finite set theory provides a rigorous foundation to multitarget tracking problems. It provides a framework to represent the full multitarget posterior in contrast to other conventional approaches. However, the computational complexity of performing multitarget recursion grows exponentially with the number of targets. The Probability Hypothesis Density (PHD) filter, which only propagates the first moment of the multitarget posterior, requires much less computational complexity. This thesis addresses some of the essential issues related to practical multitarget tracking problems such as tracking target maneuvers, stealthy targets, multitarget tracking in a distributed framework. With maneuvering targets, detecting and tracking the changes in the target motion model also becomes important and an effective solution for this problem using multiple-model based PHD filter is proposed. The proposed filter has the advantage over the other methods in that it can track a timevarying number of targets in nonlinear/ non-Gaussian systems. Recent developments in stealthy military aircraft and cruise missiles have emphasized the need to t rack low SNR targets. The conventional approach of thresholding the measurements throws away potential information and thus results in poor performance in tracking dim targets. The problem becomes even more complicated when multiple dim targets are present in the surveillance region. A PHD filter based recursive track-before-detect approach is proposed in this thesis to track multiple dim targets in a computationally efficient way. This thesis also investigates multiple target tracking using a network of sensors. Generally, sensor networks have limited energy, communication capability and computational power. The crucial consideration is what information needs to be transmitted over the network in order to perform online estimation of the current state of the monitored system, whilst attempting to minimize communication overhead. Finally, a novel continuous approximation approach for nonlinear/ non-Gaussian Bayesian tracking system based on spline interpolation is presented. The resulting filter has the advantages over the widely-known discrete particle based approximation approach in that it does not suffer from degeneracy problems and retains accurate density over the state space. The filter is general enough to be applicable to nonlinear/non-Gaussian system and the density could even be multi-modal. / Thesis / Candidate in Philosophy

<p> This dissertation uses multilevel models to test the veracity of two competing theories regarding the effect of Aboriginal language use on socioeconomic well-being. The cohesion hypothesis suggests that Aboriginal language use will contribute to a sense of ethnic identity and, in turn, to socioeconomic prosperity. The ghettoization hypothesis suggests that Aboriginal language use will reduce well-being by contributing to social and economic isolation. </p> <p> Descriptive statistics from the 2001 Census of Canada support the ghettoization hypothesis. Compared to Aboriginal people who do not use an Aboriginal language, Aboriginal language users have lower levels of educational attainment, income, labour force participation and employment. Multilevel models however, demonstrate that neither hypothesis merits unqualified support. Aboriginal language users are predicted to have lower well-being than non-speakers under some circumstances- most notably in non-Aboriginal communities. Under other circumstances, however, the opposite is true. Tests of the mechanisms by which Aboriginal language use is supposed to affect well-being also have inconsistent implications. Additional research is proposed that might clarify the apparently complex relationship between Aboriginal language use and well-being. </p> <p> Aboriginal language use in Canada is declining very rapidly. Of the dozens of Aboriginal languages used in Canada today, only a few are expected to survive into the next century. This dissertation may provide guidance to Aboriginal leaders tasked with allocating resources, as well as to politicians and policy-makers faced with increasingly urgent demands to support Aboriginal language maintenance. </p> / Thesis / Doctor of Philosophy (PhD)

Genetic predisposition to obesity presents a paradox: how do genetic variants with such a detrimental impact on human health persist through evolutionary time? Numerous hypotheses, for instance the thrifty genotype hypothesis, attempt to explain this phenomenon, yet fail to provide a satisfying answer to the modern obesity epidemic. In this critical review, I appraise existing theories explaining the evolutionary origins of obesity and explore novel biological and sociocultural agents of evolutionary change that may help explain the distribution of obesity and leanness predisposing variants in modern human populations. Gene pleiotropy and adaptations to diverse environmental niches may explain the rise and subsequent selection of obesity risk alleles. The regulation of gene expression by epigenetic mechanisms may serve as a stochastic factor affecting the manifestation of obesity phenotypes. Finally, exposure to malnutrition and disease epidemics in the wake of colonialism, culturally mediated notions of attractiveness and desirability, and diverse mating systems – including forced copulation, consanguinity and polygamy – may play a role in shaping the human genome. In short, I posit that in order to explain ethnic variation in obesity susceptibility, we must examine the origin of physiological adaptations and understand the sociocultural experiences of individuals and populations. As an imperative first step towards the identification of important drivers of obesity gene evolution, this review will inform empirical research focused on testing evolutionary theories by way of population genetics and mathematical modelling. Ultimately, these data will promote a better understanding of the aetiology of obesity and are expected to guide the development of targeted management, treatment, and prevention strategies. / Thesis / Master of Science (MSc)

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