Situated in a context of shifts towards working time flexibility, this article examines the regul... more Situated in a context of shifts towards working time flexibility, this article examines the regulation of working time in the Ontario Employment Standards Act (ESA), with a focus on excess and overtime hours. The article builds its analysis from interviews with both workers in precarious jobs and Employment Standards Officers from the Ontario Ministry of Labour (MOL), as well as administrative data from the MOL and archival records. The article argues that ESA hours of work provisions premised upon creating flexible approaches to working time have contributed to the privatization and individualization of working time regulation in ways that enhance employer control over time, exacerbate time pressures and uncertainty experienced by workers in precarious jobs and, thereby, deepen conditions of precarious employment. KEYWORDS: working time, employment standards, precarious work, Ontario.
The human salivary amylase genes display extensive copy number variation (CNV), and recent work h... more The human salivary amylase genes display extensive copy number variation (CNV), and recent work has implicated this variation in adaptation to starch-rich diets, and in association with body mass index. In this work, we use paralogue ratio tests, microsatellite analysis, read depth and fibre-FISH to demonstrate that human amylase CNV is not a smooth continuum, but is instead partitioned into distinct haplotype classes. There is a fundamental structural distinction between haplotypes containing odd or even numbers of AMY1 gene units, in turn coupled to CNV in pancreatic amylase genes AMY2A and AMY2B. Most haplotypes have one copy each of AMY2A and AMY2B and contain an odd number of copies of AMY1; consequently, most individuals have an even total number of AMY1. In contrast, haplotypes carrying an even number of AMY1 genes have rearrangements leading to CNVs of AMY2A/AMY2B. Read-depth and experimental data show that different populations harbour different proportions of these basic h...
It is commonly thought that human genetic diversity in non-African populations was shaped primari... more It is commonly thought that human genetic diversity in non-African populations was shaped primarily by an out-of-Africa dispersal 50-100 thousand yr ago (kya). Here, we present a study of 456 geographically diverse high-coverage Y chromosome sequences, including 299 newly reported samples. Applying ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192-307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.
Background. Previous studies concerning Alu IuD polymorphism in the ACE gene and ADPKD severity h... more Background. Previous studies concerning Alu IuD polymorphism in the ACE gene and ADPKD severity have used the Alu genotypes as a representative of the true biological variable, namely ACE activity. How- ever, wide individual and ethnic differences in the proportion of variance in ACE activity explained by the IuD genotype may have confounded these studies. This investigation examines the association
Hispaniola is a geotectonically complex island consisting of two palaeo-islands that docked c. 10... more Hispaniola is a geotectonically complex island consisting of two palaeo-islands that docked c. 10 Ma, with a further geological boundary subdividing the southern palaeo-island into eastern and western regions. All three regions have been isolated by marine barriers during the late Cenozoic and possess biogeographically distinct terrestrial biotas. However, there is currently little evidence to indicate whether Hispaniolan mammals show distributional patterns reflecting this geotectonic history, as the island's endemic land mammal fauna is now almost entirely extinct. We obtained samples of Hispaniolan hutia (Plagiodontia aedium), one of the two surviving Hispaniolan land mammal species, through fieldwork and historical museum collections from seven localities distributed across all three of the island's biogeographic regions. Phylogenetic analysis using mitochondrial DNA (cytochrome b) reveals a pattern of historical allopatric lineage divergence in this species, with the sp...
About 20% of all adult emergency admissions are affected by acute kidney injury (AKI) and the mor... more About 20% of all adult emergency admissions are affected by acute kidney injury (AKI) and the mortality rate is almost 25%. It has been estimated that AKI, excluding cases in the community, causes more than 10,000 preventable deaths a year in England. AKI represents a wide spectrum of injury to the kidneys, not just kidney failure, the vast majority of AKI cases start with an illness in the community. In AKI, loss of kidney function contributes to morbidity and mortality. Patients die from AKI rather than with AKI as a complication of an underlying illness. The diagnosis of AKI is currently based on a rise in creatinine, and/or reduced urine output, eGFR is not used in diagnosis. AKI may only be seen as a small rise in creatinine. The rise needs to be on a short, acute timescale to distinguish it from the slower steady rise of progressive chronic kidney disease (CKD). AKI episodes are common in patients with CKD. Such episodes are an important factor in the progression of CKD. The d...
The genetic structure of Staphylococcus aureus populations sampled from diverse regions of the gl... more The genetic structure of Staphylococcus aureus populations sampled from diverse regions of the globe have been the subject of numerous investigations. Here we describe the structure of S. aureus populations collected from the Southwest Pacific. Multi-locus sequence typing was performed on 467 isolates obtained from people with nasal colonization or bacteremia in Auckland (NZ), and patients predominantly affected by skin and soft tissue infection in Samoa, Fiji and Tonga. The predominant sequence types (STs) varied between Auckland (ST5), Fiji (ST30), and Samoa (ST1), however, the overall genetic diversity within each region did not differ significantly between locations. Divergent Clonal Complex 75 (CC75) strains were isolated in Auckland and Fiji. When diversity of the Southwest Pacific populations was compared with those previously described from Asia, Europe, North America and Africa no significant differences were detected. With the exception of CC75 strains, the global collecti...
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, Jan 15, 2014
Our aim was to assess national prescribing trends and determine longitudinal resistance patterns ... more Our aim was to assess national prescribing trends and determine longitudinal resistance patterns for topical antimicrobials in New Zealand. We observed a dramatic increase in fusidic acid (FA) resistance, and clonal expansion of FA-resistant Staphylococcus aureus. This increase was concurrent with a significant national increase in topical FA dispensing.
We sequenced genomes from a ~7,000 year old early farmer from Stuttgart in Germany, an ~8,000 yea... more We sequenced genomes from a ~7,000 year old early farmer from Stuttgart in Germany, an ~8,000 year old hunter-gatherer from Luxembourg, and seven ~8,000 year old hunter-gatherers from southern Sweden. We analyzed these data together with other ancient genomes and 2,345 contemporary humans to show that the great majority of present-day Europeans derive from at least three highly differentiated populations: West European Hunter-Gatherers (WHG), who contributed ancestry to all Europeans but not to Near Easterners; Ancient North Eurasians (ANE), who were most closely related to Upper Paleolithic Siberians and contributed to both Europeans and Near Easterners; and Early European Farmers (EEF), who were mainly of Near Eastern origin but also harbored WHG-related ancestry. We model these populations' deep relationships and show that EEF had ~44% ancestry from a "Basal Eurasian" lineage that split prior to the diversification of all other non-African lineages.
We would also like to thank the faculty, staff, students, and supporters who participated and ass... more We would also like to thank the faculty, staff, students, and supporters who participated and assisted in making this year's Student Research Celebration a success.
In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, th... more In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, the last-known resting place of King Richard III. Archaeological, osteological and radiocarbon dating data were consistent with these being his remains. Here we report DNA analyses of both the skeletal remains and living relatives of Richard III. We find a perfect mitochondrial DNA match between the sequence obtained from the remains and one living relative, and a single-base substitution when compared with a second relative. Y-chromosome haplotypes from male-line relatives and the remains do not match, which could be attributed to a false-paternity event occurring in any of the intervening generations. DNA-predicted hair and eye colour are consistent with Richard's appearance in an early portrait. We calculate likelihood ratios for the non-genetic and genetic data separately, and combined, and conclude that the evidence for the remains being those of Richard III is overwhelming.
Background: We performed a prospective audit of screening for asymptomatic sexually transmissible... more Background: We performed a prospective audit of screening for asymptomatic sexually transmissible infections (STIs), during an intensive effort to screen all patients at our hospital-based HIV clinic. We aimed to measure the effectiveness and resource implications of our screening program. Methods: All outpatients who attended during an 8-month period were invited to take part in opt-out screening for chlamydia (Chlamydia trachomatis), gonorrhoea (Neisseria gonorrhoeae) and syphilis. Participants completed a brief questionnaire, were asked about current symptoms of STIs and self-collected specimens for laboratory testing. Results: The majority (535 out of 673, 80%) of the patients who were asked to participate provided specimens for screening. No chlamydia, gonorrhoea or syphilis infections were identified in women (n = 91) or in heterosexual men (n = 76). In contrast, 34 out of 368 (10%) of men who have sex with men tested positive (chlamydia, 25; gonorrhoea, 2; chlamydia and gonorrhoea, 2; syphilis, 5). The laboratory cost of diagnosing each case of rectal chlamydia or gonorrhoea (NZ$664) was substantially lower than the cost of diagnosing each case of urethral infection (NZ$5309). Conclusions: There was high uptake of screening among our clinic population, who preferred screening to be performed at the hospital clinic. The yield of screening men who have sex with men warrants continued annual screening for rectal gonorrhoea and chlamydia and for syphilis.
Proceedings of the Royal Society B: Biological Sciences, 2007
The extinct aurochs (Bos primigenius primigenius) was a large type of cattle that ranged over alm... more The extinct aurochs (Bos primigenius primigenius) was a large type of cattle that ranged over almost the whole Eurasian continent. The aurochs is the wild progenitor of modern cattle, but it is unclear whether European aurochs contributed to this process. To provide new insights into the demographic history of aurochs and domestic cattle, we have generated high-confidence mitochondrial DNA sequences from 59 archaeological skeletal finds, which were attributed to wild European cattle populations based on their chronological date and/or morphology. All pre-Neolithic aurochs belonged to the previously designated P haplogroup, indicating that this represents the Late Glacial Central European signature. We also report one new and highly divergent haplotype in a Neolithic aurochs sample from Germany, which points to greater variability during the Pleistocene. Furthermore, the Neolithic and Bronze Age samples that were classified with confidence as European aurochs using morphological criteria all carry P haplotype mitochondrial DNA, suggesting continuity of Late Glacial and Early Holocene aurochs populations in Europe. Bayesian analysis indicates that recent population growth gives a significantly better fit to our data than a constant-sized population, an observation consistent with a postglacial expansion scenario, possibly from a single European refugial population. Previous work has shown that most ancient and modern European domestic cattle carry haplotypes previously designated T. This, in combination with our new finding of a T haplotype in a very Early Neolithic site in Syria, lends persuasive support to a scenario whereby gracile Near Eastern domestic populations, carrying predominantly T haplotypes, replaced P haplotype-carrying robust autochthonous aurochs populations in Europe, from the Early Neolithic onward. During the period of coexistence, it appears that domestic cattle were kept separate from wild aurochs and introgression was extremely rare.
Proceedings of the Royal Society B: Biological Sciences, 2006
The role of migration in the Anglo-Saxon transition in England remains controversial. Archaeologi... more The role of migration in the Anglo-Saxon transition in England remains controversial. Archaeological and historical evidence is inconclusive, but current estimates of the contribution of migrants to the English population range from less than 10 000 to as many as 200 000. In contrast, recent studies based on Y-chromosome variation posit a considerably higher contribution to the modern English gene pool (50-100%). Historical evidence suggests that following the Anglo-Saxon transition, people of indigenous ethnicity were at an economic and legal disadvantage compared to those having Anglo-Saxon ethnicity. It is likely that such a disadvantage would lead to differential reproductive success. We examine the effect of differential reproductive success, coupled with limited intermarriage between distinct ethnic groups, on the spread of genetic variants. Computer simulations indicate that a social structure limiting intermarriage between indigenous Britons and an initially small Anglo-Saxon immigrant population provide a plausible explanation of the high degree of Continental male-line ancestry in England.
Philosophical Transactions of the Royal Society B: Biological Sciences, 2011
Niche construction is the process by which organisms construct important components of their loca... more Niche construction is the process by which organisms construct important components of their local environment in ways that introduce novel selection pressures. Lactase persistence is one of the clearest examples of niche construction in humans. Lactase is the enzyme responsible for the digestion of the milk sugar lactose and its production decreases after the weaning phase in most mammals, including most humans. Some humans, however, continue to produce lactase throughout adulthood, a trait known as lactase persistence. In European populations, a single mutation (213910*T ) explains the distribution of the phenotype, whereas several mutations are associated with it in Africa and the Middle East. Current estimates for the age of lactase persistence-associated alleles bracket those for the origins of animal domestication and the culturally transmitted practice of dairying. We report new data on the distribution of 213910*T and summarize genetic studies on the diversity of lactase persistence worldwide. We review relevant archaeological data and describe three simulation studies that have shed light on the evolution of this trait in Europe. These studies illustrate how genetic and archaeological information can be integrated to bring new insights to the origins and spread of lactase persistence. Finally, we discuss possible improvements to these models.
Background-The drug-metabolizing enzyme flavin-containing monooxygenase 2 (FMO2) is the predomina... more Background-The drug-metabolizing enzyme flavin-containing monooxygenase 2 (FMO2) is the predominant FMO isoform present in the lung of most mammals, including non-human primates. All Europeans and Asians tested have been shown to be homozygous for a nonfunctional variant, FMO2*2A, which contains a premature stop codon due to a single-nucleotide change in exon 9 (g. 23238C > T). The ancestral allele, FMO2*1, encodes a functionally active protein and has been found in African-Americans (26%) and Hispanics (2% to 7%). Possessing this variant increases the risk of pulmonary toxicity when exposed to thioureas, a widely used class of industrial compounds. FMO2 may also be involved in the metabolism of drugs that are used to treat diseases that are prevalent in Africa.
Following its initial arrival in SE Europe 8,500 years ago agriculture spread throughout the cont... more Following its initial arrival in SE Europe 8,500 years ago agriculture spread throughout the continent, changing food production and consumption patterns and increasing population densities. Here we show that, in contrast to the steady population growth usually assumed, the introduction of agriculture into Europe was followed by a boom-and-bust pattern in the density of regional populations. We demonstrate that summed calibrated radiocarbon date distributions and simulation can be used to test the significance of these demographic booms and busts in the context of uncertainty in the radiocarbon date calibration curve and archaeological sampling. We report these results for Central and Northwest Europe between 8,000 and 4,000 cal. BP and investigate the relationship between these patterns and climate. However, we find no evidence to support a relationship. Our results thus suggest that the demographic patterns may have arisen from endogenous causes, although this remains speculative.
Situated in a context of shifts towards working time flexibility, this article examines the regul... more Situated in a context of shifts towards working time flexibility, this article examines the regulation of working time in the Ontario Employment Standards Act (ESA), with a focus on excess and overtime hours. The article builds its analysis from interviews with both workers in precarious jobs and Employment Standards Officers from the Ontario Ministry of Labour (MOL), as well as administrative data from the MOL and archival records. The article argues that ESA hours of work provisions premised upon creating flexible approaches to working time have contributed to the privatization and individualization of working time regulation in ways that enhance employer control over time, exacerbate time pressures and uncertainty experienced by workers in precarious jobs and, thereby, deepen conditions of precarious employment. KEYWORDS: working time, employment standards, precarious work, Ontario.
The human salivary amylase genes display extensive copy number variation (CNV), and recent work h... more The human salivary amylase genes display extensive copy number variation (CNV), and recent work has implicated this variation in adaptation to starch-rich diets, and in association with body mass index. In this work, we use paralogue ratio tests, microsatellite analysis, read depth and fibre-FISH to demonstrate that human amylase CNV is not a smooth continuum, but is instead partitioned into distinct haplotype classes. There is a fundamental structural distinction between haplotypes containing odd or even numbers of AMY1 gene units, in turn coupled to CNV in pancreatic amylase genes AMY2A and AMY2B. Most haplotypes have one copy each of AMY2A and AMY2B and contain an odd number of copies of AMY1; consequently, most individuals have an even total number of AMY1. In contrast, haplotypes carrying an even number of AMY1 genes have rearrangements leading to CNVs of AMY2A/AMY2B. Read-depth and experimental data show that different populations harbour different proportions of these basic h...
It is commonly thought that human genetic diversity in non-African populations was shaped primari... more It is commonly thought that human genetic diversity in non-African populations was shaped primarily by an out-of-Africa dispersal 50-100 thousand yr ago (kya). Here, we present a study of 456 geographically diverse high-coverage Y chromosome sequences, including 299 newly reported samples. Applying ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192-307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.
Background. Previous studies concerning Alu IuD polymorphism in the ACE gene and ADPKD severity h... more Background. Previous studies concerning Alu IuD polymorphism in the ACE gene and ADPKD severity have used the Alu genotypes as a representative of the true biological variable, namely ACE activity. How- ever, wide individual and ethnic differences in the proportion of variance in ACE activity explained by the IuD genotype may have confounded these studies. This investigation examines the association
Hispaniola is a geotectonically complex island consisting of two palaeo-islands that docked c. 10... more Hispaniola is a geotectonically complex island consisting of two palaeo-islands that docked c. 10 Ma, with a further geological boundary subdividing the southern palaeo-island into eastern and western regions. All three regions have been isolated by marine barriers during the late Cenozoic and possess biogeographically distinct terrestrial biotas. However, there is currently little evidence to indicate whether Hispaniolan mammals show distributional patterns reflecting this geotectonic history, as the island's endemic land mammal fauna is now almost entirely extinct. We obtained samples of Hispaniolan hutia (Plagiodontia aedium), one of the two surviving Hispaniolan land mammal species, through fieldwork and historical museum collections from seven localities distributed across all three of the island's biogeographic regions. Phylogenetic analysis using mitochondrial DNA (cytochrome b) reveals a pattern of historical allopatric lineage divergence in this species, with the sp...
About 20% of all adult emergency admissions are affected by acute kidney injury (AKI) and the mor... more About 20% of all adult emergency admissions are affected by acute kidney injury (AKI) and the mortality rate is almost 25%. It has been estimated that AKI, excluding cases in the community, causes more than 10,000 preventable deaths a year in England. AKI represents a wide spectrum of injury to the kidneys, not just kidney failure, the vast majority of AKI cases start with an illness in the community. In AKI, loss of kidney function contributes to morbidity and mortality. Patients die from AKI rather than with AKI as a complication of an underlying illness. The diagnosis of AKI is currently based on a rise in creatinine, and/or reduced urine output, eGFR is not used in diagnosis. AKI may only be seen as a small rise in creatinine. The rise needs to be on a short, acute timescale to distinguish it from the slower steady rise of progressive chronic kidney disease (CKD). AKI episodes are common in patients with CKD. Such episodes are an important factor in the progression of CKD. The d...
The genetic structure of Staphylococcus aureus populations sampled from diverse regions of the gl... more The genetic structure of Staphylococcus aureus populations sampled from diverse regions of the globe have been the subject of numerous investigations. Here we describe the structure of S. aureus populations collected from the Southwest Pacific. Multi-locus sequence typing was performed on 467 isolates obtained from people with nasal colonization or bacteremia in Auckland (NZ), and patients predominantly affected by skin and soft tissue infection in Samoa, Fiji and Tonga. The predominant sequence types (STs) varied between Auckland (ST5), Fiji (ST30), and Samoa (ST1), however, the overall genetic diversity within each region did not differ significantly between locations. Divergent Clonal Complex 75 (CC75) strains were isolated in Auckland and Fiji. When diversity of the Southwest Pacific populations was compared with those previously described from Asia, Europe, North America and Africa no significant differences were detected. With the exception of CC75 strains, the global collecti...
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, Jan 15, 2014
Our aim was to assess national prescribing trends and determine longitudinal resistance patterns ... more Our aim was to assess national prescribing trends and determine longitudinal resistance patterns for topical antimicrobials in New Zealand. We observed a dramatic increase in fusidic acid (FA) resistance, and clonal expansion of FA-resistant Staphylococcus aureus. This increase was concurrent with a significant national increase in topical FA dispensing.
We sequenced genomes from a ~7,000 year old early farmer from Stuttgart in Germany, an ~8,000 yea... more We sequenced genomes from a ~7,000 year old early farmer from Stuttgart in Germany, an ~8,000 year old hunter-gatherer from Luxembourg, and seven ~8,000 year old hunter-gatherers from southern Sweden. We analyzed these data together with other ancient genomes and 2,345 contemporary humans to show that the great majority of present-day Europeans derive from at least three highly differentiated populations: West European Hunter-Gatherers (WHG), who contributed ancestry to all Europeans but not to Near Easterners; Ancient North Eurasians (ANE), who were most closely related to Upper Paleolithic Siberians and contributed to both Europeans and Near Easterners; and Early European Farmers (EEF), who were mainly of Near Eastern origin but also harbored WHG-related ancestry. We model these populations' deep relationships and show that EEF had ~44% ancestry from a "Basal Eurasian" lineage that split prior to the diversification of all other non-African lineages.
We would also like to thank the faculty, staff, students, and supporters who participated and ass... more We would also like to thank the faculty, staff, students, and supporters who participated and assisted in making this year's Student Research Celebration a success.
In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, th... more In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, the last-known resting place of King Richard III. Archaeological, osteological and radiocarbon dating data were consistent with these being his remains. Here we report DNA analyses of both the skeletal remains and living relatives of Richard III. We find a perfect mitochondrial DNA match between the sequence obtained from the remains and one living relative, and a single-base substitution when compared with a second relative. Y-chromosome haplotypes from male-line relatives and the remains do not match, which could be attributed to a false-paternity event occurring in any of the intervening generations. DNA-predicted hair and eye colour are consistent with Richard's appearance in an early portrait. We calculate likelihood ratios for the non-genetic and genetic data separately, and combined, and conclude that the evidence for the remains being those of Richard III is overwhelming.
Background: We performed a prospective audit of screening for asymptomatic sexually transmissible... more Background: We performed a prospective audit of screening for asymptomatic sexually transmissible infections (STIs), during an intensive effort to screen all patients at our hospital-based HIV clinic. We aimed to measure the effectiveness and resource implications of our screening program. Methods: All outpatients who attended during an 8-month period were invited to take part in opt-out screening for chlamydia (Chlamydia trachomatis), gonorrhoea (Neisseria gonorrhoeae) and syphilis. Participants completed a brief questionnaire, were asked about current symptoms of STIs and self-collected specimens for laboratory testing. Results: The majority (535 out of 673, 80%) of the patients who were asked to participate provided specimens for screening. No chlamydia, gonorrhoea or syphilis infections were identified in women (n = 91) or in heterosexual men (n = 76). In contrast, 34 out of 368 (10%) of men who have sex with men tested positive (chlamydia, 25; gonorrhoea, 2; chlamydia and gonorrhoea, 2; syphilis, 5). The laboratory cost of diagnosing each case of rectal chlamydia or gonorrhoea (NZ$664) was substantially lower than the cost of diagnosing each case of urethral infection (NZ$5309). Conclusions: There was high uptake of screening among our clinic population, who preferred screening to be performed at the hospital clinic. The yield of screening men who have sex with men warrants continued annual screening for rectal gonorrhoea and chlamydia and for syphilis.
Proceedings of the Royal Society B: Biological Sciences, 2007
The extinct aurochs (Bos primigenius primigenius) was a large type of cattle that ranged over alm... more The extinct aurochs (Bos primigenius primigenius) was a large type of cattle that ranged over almost the whole Eurasian continent. The aurochs is the wild progenitor of modern cattle, but it is unclear whether European aurochs contributed to this process. To provide new insights into the demographic history of aurochs and domestic cattle, we have generated high-confidence mitochondrial DNA sequences from 59 archaeological skeletal finds, which were attributed to wild European cattle populations based on their chronological date and/or morphology. All pre-Neolithic aurochs belonged to the previously designated P haplogroup, indicating that this represents the Late Glacial Central European signature. We also report one new and highly divergent haplotype in a Neolithic aurochs sample from Germany, which points to greater variability during the Pleistocene. Furthermore, the Neolithic and Bronze Age samples that were classified with confidence as European aurochs using morphological criteria all carry P haplotype mitochondrial DNA, suggesting continuity of Late Glacial and Early Holocene aurochs populations in Europe. Bayesian analysis indicates that recent population growth gives a significantly better fit to our data than a constant-sized population, an observation consistent with a postglacial expansion scenario, possibly from a single European refugial population. Previous work has shown that most ancient and modern European domestic cattle carry haplotypes previously designated T. This, in combination with our new finding of a T haplotype in a very Early Neolithic site in Syria, lends persuasive support to a scenario whereby gracile Near Eastern domestic populations, carrying predominantly T haplotypes, replaced P haplotype-carrying robust autochthonous aurochs populations in Europe, from the Early Neolithic onward. During the period of coexistence, it appears that domestic cattle were kept separate from wild aurochs and introgression was extremely rare.
Proceedings of the Royal Society B: Biological Sciences, 2006
The role of migration in the Anglo-Saxon transition in England remains controversial. Archaeologi... more The role of migration in the Anglo-Saxon transition in England remains controversial. Archaeological and historical evidence is inconclusive, but current estimates of the contribution of migrants to the English population range from less than 10 000 to as many as 200 000. In contrast, recent studies based on Y-chromosome variation posit a considerably higher contribution to the modern English gene pool (50-100%). Historical evidence suggests that following the Anglo-Saxon transition, people of indigenous ethnicity were at an economic and legal disadvantage compared to those having Anglo-Saxon ethnicity. It is likely that such a disadvantage would lead to differential reproductive success. We examine the effect of differential reproductive success, coupled with limited intermarriage between distinct ethnic groups, on the spread of genetic variants. Computer simulations indicate that a social structure limiting intermarriage between indigenous Britons and an initially small Anglo-Saxon immigrant population provide a plausible explanation of the high degree of Continental male-line ancestry in England.
Philosophical Transactions of the Royal Society B: Biological Sciences, 2011
Niche construction is the process by which organisms construct important components of their loca... more Niche construction is the process by which organisms construct important components of their local environment in ways that introduce novel selection pressures. Lactase persistence is one of the clearest examples of niche construction in humans. Lactase is the enzyme responsible for the digestion of the milk sugar lactose and its production decreases after the weaning phase in most mammals, including most humans. Some humans, however, continue to produce lactase throughout adulthood, a trait known as lactase persistence. In European populations, a single mutation (213910*T ) explains the distribution of the phenotype, whereas several mutations are associated with it in Africa and the Middle East. Current estimates for the age of lactase persistence-associated alleles bracket those for the origins of animal domestication and the culturally transmitted practice of dairying. We report new data on the distribution of 213910*T and summarize genetic studies on the diversity of lactase persistence worldwide. We review relevant archaeological data and describe three simulation studies that have shed light on the evolution of this trait in Europe. These studies illustrate how genetic and archaeological information can be integrated to bring new insights to the origins and spread of lactase persistence. Finally, we discuss possible improvements to these models.
Background-The drug-metabolizing enzyme flavin-containing monooxygenase 2 (FMO2) is the predomina... more Background-The drug-metabolizing enzyme flavin-containing monooxygenase 2 (FMO2) is the predominant FMO isoform present in the lung of most mammals, including non-human primates. All Europeans and Asians tested have been shown to be homozygous for a nonfunctional variant, FMO2*2A, which contains a premature stop codon due to a single-nucleotide change in exon 9 (g. 23238C > T). The ancestral allele, FMO2*1, encodes a functionally active protein and has been found in African-Americans (26%) and Hispanics (2% to 7%). Possessing this variant increases the risk of pulmonary toxicity when exposed to thioureas, a widely used class of industrial compounds. FMO2 may also be involved in the metabolism of drugs that are used to treat diseases that are prevalent in Africa.
Following its initial arrival in SE Europe 8,500 years ago agriculture spread throughout the cont... more Following its initial arrival in SE Europe 8,500 years ago agriculture spread throughout the continent, changing food production and consumption patterns and increasing population densities. Here we show that, in contrast to the steady population growth usually assumed, the introduction of agriculture into Europe was followed by a boom-and-bust pattern in the density of regional populations. We demonstrate that summed calibrated radiocarbon date distributions and simulation can be used to test the significance of these demographic booms and busts in the context of uncertainty in the radiocarbon date calibration curve and archaeological sampling. We report these results for Central and Northwest Europe between 8,000 and 4,000 cal. BP and investigate the relationship between these patterns and climate. However, we find no evidence to support a relationship. Our results thus suggest that the demographic patterns may have arisen from endogenous causes, although this remains speculative.
In October 2010, the provincial government of Ontario, Canada enacted the Open for Business Act (... more In October 2010, the provincial government of Ontario, Canada enacted the Open for Business Act (OBA). A central component of the OBA is its provisions aiming to streamline the enforcement of Ontario’s Employment Standards Act (ESA). The OBA’s changes to the ESA are an attempt to manage a crisis of employment
standards (ES) enforcement, arising from decades of ineffective regulation, by entrenching an individualised enforcement model. The Act aims to streamline enforcement by screening people assumed to be lacking definitive proof of violations out of the complaints process. The OBA therefore produces a new category
of ‘illegitimate claimants’ and attributes administrative backlogs to these people. Instead of improving the protection of workers, the OBA embeds new racialised and gendered modes of exclusion in the ES enforcement process.
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Papers by Mark P Thomas
KEYWORDS: working time, employment standards, precarious work, Ontario.
KEYWORDS: working time, employment standards, precarious work, Ontario.
standards (ES) enforcement, arising from decades of ineffective regulation, by entrenching an individualised enforcement model. The Act aims to streamline enforcement by screening people assumed to be lacking definitive proof of violations out of the complaints process. The OBA therefore produces a new category
of ‘illegitimate claimants’ and attributes administrative backlogs to these people. Instead of improving the protection of workers, the OBA embeds new racialised and gendered modes of exclusion in the ES enforcement process.