geographic distance
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Ethnogenesis of Kazakhs took place in Central Asia, a region of high genetic and cultural diversity. Even though archaeological and historical studies have shed some light on the formation of modern Kazakhs, the process of establishment of hierarchical socioeconomic structure in the Steppe remains contentious. In this study, we analyzed haplotype variation at 15 Y-chromosomal short-tandem-repeats obtained from 1171 individuals from 24 tribes representing the three socio-territorial subdivisions (Senior, Middle and Junior zhuz) in Kazakhstan to comprehensively characterize the patrilineal genetic architecture of the Kazakh Steppe. In total, 577 distinct haplotypes were identified belonging to one of 20 haplogroups; 16 predominant haplogroups were confirmed by SNP-genotyping. The haplogroup distribution was skewed towards C2-M217, present in all tribes at a global frequency of 51.9%. Despite signatures of spatial differences in haplotype frequencies, a Mantel test failed to detect a statistically significant correlation between genetic and geographic distance between individuals. An analysis of molecular variance found that ∼8.9% of the genetic variance among individuals was attributable to differences among zhuzes and ∼20% to differences among tribes within zhuzes. The STRUCTURE analysis of the 1164 individuals indicated the presence of 20 ancestral groups and a complex three-subclade organization of the C2-M217 haplogroup in Kazakhs, a result supported by the multidimensional scaling analysis. Additionally, while the majority of the haplotypes and tribes overlapped, a distinct cluster of the O2 haplogroup, mostly of the Naiman tribe, was observed. Thus, firstly, our analysis indicated that the majority of Kazakh tribes share deep heterogeneous patrilineal ancestries, while a smaller fraction of them are descendants of a founder paternal ancestor. Secondly, we observed a high frequency of the C2-M217 haplogroups along the southern border of Kazakhstan, broadly corresponding to both the path of the Mongolian invasion and the ancient Silk Road. Interestingly, we detected three subclades of the C2-M217 haplogroup that broadly exhibits zhuz-specific clustering. Further study of Kazakh haplotypes variation within a Central Asian context is required to untwist this complex process of ethnogenesis.

Prior research has found evidence that country factors and management styles influence earnings management decisions in various geographic locations. Extending this research, we utilize an experimental setting to isolate the effect of geographic distance on the willingness to manage earnings in a near/distant location. In an initial experiment, we find less acceptable earnings management methods generate greater concerns about the method (ethicality and riskiness) leading to less willingness to manage earnings. Yet, greater geographic distance between the decisionmaker and reporting location attenuates these concerns, resulting in increased willingness to use a less acceptable method. In contrast, individuals are willing to use a more acceptable method to manage earnings regardless of geographic distance. These findings are consistent with construal level theory (CLT) and are corroborated in a second experiment where we find that greater geographic distance reduces managers’ focus on the means of earnings management, thereby reducing concerns about the method.

Apis mellifera Linnaeus, 1758 is one of the most economically valuable insects which plays significant role in human medicine, nutrition and crop pollination. The morphometric variations of honeybee from different locations of the southern guinea and northern guinea savannah ecological zone of Nigeria were studied. Fifteen morphological traits were measured for variation on six hundred (600) worker honeybee samples purposively collected from ten different locations within the ecological zone. Data collected were subjected to one-way Analysis of Variance (ANOVA), SNK test (α=0.05) and Pearson correlation between morphometric characters were determined. At the same time a dendrogram of morphological proximity based on the fifteen morphological features was constructed. Results showed that morphometry variation (p<0.05) existed within the honeybee population in the guinea savannah agro-ecological zone of Nigeria, high morphological similarities were observed in the tibia length of the hind leg and the thorax length. The honeybee samples were classified into two distinct morphoclusters (A and B). Honeybee samples within morphocluster A were closely related in terms of the examined morphometric features and geographic distance (CV=1.65). In contrast, within cluster B, honeybee samples were closely related despite the vast geographical distance (CV=3.30, p<0.05). The body length was significantly positively correlated with the leg size, while hind wing length was positively associated with the proboscis, abdominal, thoracic, body length and hooks. Morphometric variations found in A. mellifera of guinea agro-ecological zone could significantly impact conservation and future bee breeding programmes of Nigeria.

In the present article we use geometric microliths (a specific type of arrowhead) and Approximate Bayesian Computation (ABC) in order to evaluate possible origin points and expansion routes for the Neolithic in the Iberian Peninsula. In order to do so, we divide the Iberian Peninsula in four areas (Ebro river, Catalan shores, Xúquer river and Guadalquivir river) and we sample the geometric microliths existing in the sites with the oldest radiocarbon dates for each zone. On this data, we perform a partial Mantel test with three matrices: geographic distance matrix, cultural distance matrix and chronological distance matrix. After this is done, we simulate a series of partial Mantel tests where we alter the chronological matrix by using an expansion model with randomised origin points, and using the distribution of the observed partial Mantel test’s results as a summary statistic within an Approximate Bayesian Computation-Sequential Monte-Carlo (ABC-SMC) algorithm framework. Our results point clearly to a Neolithic expansion route following the Northern Mediterranean, whilst the Southern Mediterranean route could also find support and should be further discussed. The most probable origin points focus on the Xúquer river area.

Disentangling the mechanisms underlying spatial distribution of genetic variation into those due to environment or physical barriers from mere geographic distance is challenging in complex landscapes. The Andean uplift represents one of the most heterogeneous habitats where these questions remain unexplored as multiple mechanisms might interact, confounding their relative roles. We explore this broad question in the leaf-cutting ant Atta cephalotes, a species distributed across the Andes Mountains using nuclear microsatellite markers and mtCOI gene sequences. We investigate spatial genetic divergence across the Western range of Northern Andes in Colombia by testing the relative role of alternative scenarios of population divergence, including geographic distance (IBD), climatic conditions (IBE), and physical barriers due to the Andes Mountains (IBB). Our results reveal substantial genetic differentiation among A. cephalotes populations for both types of markers, but only nuclear divergence followed a hierarchical pattern with multiple models of genetic divergence imposed by the Western range. Model selection showed that IBD, IBE (temperature and precipitation), and IBB (Andes mountains) models, often proposed as individual drivers of genetic divergence, interact, and explain up to 33% of genetic divergence in A. cephalotes. IBE models remained significant after accounting for IBD, suggesting that environmental factors play a more prominent role when compared to IBB. These factors in combination with idiosyncratic dispersal patterns of ants appear to determine hierarchical patterns of gene flow. This study enriches our understanding of the forces shaping population divergence in complex habitat landscapes.

This study provides a historical typological Optimality Theoretic analysis of the treatment of potential super-heavy syllables in six Arabic varieties: Hijazi, Egyptian, Emirati, Kuwaiti, Algerian, and Palestinian. The analysis in this study uses the same violable OT constraints for all languages, and the differences between the grammars are represented by the order in which the constraints are ranked relative to one another. The similarities and differences between these varieties are examined from the point of view of one approach to historical OT (Cho 1998), which states that individual pairs of constraints may be ranked or unranked in relation to one another, one operation at a time, meaning that switching the order of two constraints takes two steps historically. According to Cho (1998, 45), “each step of a sound change should be viewed as a change in the ranking of constraints.” Cho’s approach in detecting the historical typological differences between varieties by counting the steps of constraint reranking is compatible with a common approach to historical linguistics. Specifically, Wichmann et al. (2010) provide a quantitative method for determining the geographic homeland of a group of related languages, which takes into account a simple linguistic-difference metric and the geographic distance between the languages. Using constraint reranking in place of Wichmann et al.’s linguistic-difference metric to calculate the homeland of Arabic dialects results in an area around Hijaz as the homeland of Arabic dialects, since Hijazi, Egyptian and Emirati dialects form a cluster of geographically close, but linguistically diverse dialects.

This paper theoretically analyzed the influence of symbiosis intimacy, cultural coupling, betrayal cost, degree of lock-in, geographic distance, and economic development on the stability of the coupling symbiosis network of industry-university-research (IUR), and conducted empirical analysis. The study found that symbiosis intimacy, cultural coupling, betrayal cost, degree of lock-in, and economic development all play a role in promoting the stability of the coupling symbiosis network of IUR, while geographical location is related to the stability of the coupling symbiosis network of IUR, but does not have a direct impact. Based on the empirical analysis results, the countermeasures and suggestions to improve the stability of coupling symbiosis network of the IUR were proposed.

The processes governing soil bacteria biogeography are still not fully understood. It remains unknown how the importance of environmental filtering and dispersal differs between bacterial taxonomic and functional biogeography, and whether their importance is scale-dependent. We sampled soils at 195 plots across the Tibet plateau, with distances among plots ranging from 20 m to 1 550 km. Taxonomic composition of bacterial community was characterized by 16S amplicon sequencing, and functional community composition by qPCR targeting 9 functional groups involved in N dynamics. Twelve climatic and soil characteristics were also measured. Both taxonomic and functional dissimilarities were more related to environmental dissimilarity than geographic distance. Taxonomic dissimilarity was mostly explained by soil pH and organic matter, while functional dissimilarity was mostly linked to moisture, temperature and N, P and C availabilities. The roles of environmental filtering and dispersal were, however, scale-dependent and varied between taxonomic and functional dissimilarities, with distance affecting taxonomic dissimilarity over short distances (<~300 km) and functional dissimilarity over long distances (>~600 km). The importance of different environmental predictors varied across scales more for functional than taxonomic dissimilarity. Our results demonstrate how biodiversity dimension (taxonomic versus functional) and spatial scale strongly influence the conclusions derived from bacterial biogeography studies.

<p>This thesis consists of three empirical essays on Foreign Direct Investment (FDI) and Small Medium Enterprise (SME) access to finance. The first essay examines determinants of Chinese Outward Direct Investment (ODI) in infrastructure sectors. This study focuses on the role of host country institutions, macroeconomic stability and geography on attracting Chinese ODI. Utilizing micro-level project data over the years 2005 to 2016, results show that Chinese infrastructure investments are attracted to countries with a limited fiscal space but strong institutions. We also find that geographic distance, cultural proximity, Free Trade Agreement with China, country size are important factors in attracting Chinese investments. The second essay studies SME access to finance in Asia. We investigate the relative importance of external finance vis-à-vis internal finance for SME and larger firms and examine how SME characteristics associated with the extent of their bank borrowing. Results indicate that bank borrowing and line of credit availability are positively associated with financial audit, managerial experience, export participation, and ISO certificate, while it is negatively associated with foreign ownership and SME status. Our research suggests that access to finance is an important concern in Asia and government intervention targeting improvement in credit guarantee systems, monitoring and credit scoring can help easing the constraints for SME access to external finance. Finally, the third essay examines the role of infrastructure investment deals as a signaling on attracting FDI. Intriguingly, we find that infrastructure deals produce a negative signal to MNEs’ decision making for developing countries. We look for several channels in which the negative signaling effect can pass through. Findings suggest that increase in global risk aversion stemming from global financial crisis and country specific risk level are the main factors behind the negative signalling effect.</p>