Showing papers on "Human migration published in 2018"
TL;DR: Genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans is presented, finding limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and excludes migration as an important mechanism of spread between these two regions.
Abstract: From around 2750 to 2500 bc, Bell Beaker pottery became widespread across western and central Europe, before it disappeared between 2200 and 1800 bc. The forces that propelled its expansion are a matter of long-standing debate, and there is support for both cultural diffusion and migration having a role in this process. Here we present genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans, including 226 individuals associated with Beaker-complex artefacts. We detected limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and thus exclude migration as an important mechanism of spread between these two regions. However, migration had a key role in the further dissemination of the Beaker complex. We document this phenomenon most clearly in Britain, where the spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain's gene pool within a few hundred years, continuing the east-to-west expansion that had brought steppe-related ancestry into central and northern Europe over the previous centuries.
479 citations
TL;DR: In this article, the authors identify patterns in how households adapt to increased sea/freshwater flooding and soil salinity, and analyze nationally representative socioeconomic and migration data against a suite of environmental variables constructed at the sub-district level.
Abstract: Climate change is not only altering weather patterns but also accelerating sea-level rise, leading to increased inundation and saline contamination of soils. Given projected sea-level rise, it is imperative to examine the extent to which farmers in coastal Bangladesh can adapt by diversifying economic activities before resorting to migration within and across borders. Here, to identify patterns in how households adapt to increased sea/freshwater flooding and soil salinity, we analyse nationally representative socioeconomic and migration data against a suite of environmental variables constructed at the sub-district level. Our results show that inundation alone has negligible effects on migration and agricultural production. However, gradual increases in soil salinity correspond to increasing diversification into aquaculture and internal migration of household members. Salinity is also found to have direct effects on internal and international migration even after controlling for income losses, with mobility restricted to certain locations within Bangladesh. Our study suggests that migration is driven, in part, by the adverse consequences of salinity on crop production. Projected sea-level rise and increased flooding threaten coastal agriculture. Gradual increases in soil salinity, but not inundation alone, are shown to correspond to increasing diversification into aquaculture and higher levels of internal migration.
187 citations
TL;DR: This paper examines the links between climate change, migration, and health, considering diverse migration responses, including immobility, forced displacement and planned migration, as well as the associated health risks and opportunities in different contexts.
Abstract: Changes in climate, in conjunction with other drivers of mobility, shape human migration. While there is an increasing focus on the adaptive potential of migration, the health impacts of climate-related migration, including planned relocation and forced displacement, have not been thoroughly examined. The Intergovernmental Panel on Climate Change stated that migration is currently, and will increasingly be, influenced by environmental degradation and climate change, and that it needs to be addressed in a focused and coordinated manner. This paper examines the links between climate change, migration, and health, considering diverse migration responses, including immobility, forced displacement and planned migration, as well as the associated health risks and opportunities in different contexts. Using case studies, the paper illustrates strategies to reduce the health risks associated with climate change-related migration. While there is an increasing body of research examining the climate change–migration nexus, a dual approach is now required. This approach must include debate and further research regarding the health consequences and responses associated with climate migration as well as immediate strengthening of health systems to make them both climate resilient and migrant inclusive.
134 citations
TL;DR: These findings show that access to migrant networks enables climate-related mobility in the poorest districts, suggesting a viable pathway to overcome mobility constraints.
Abstract: Research shows that the association between adverse climate conditions and human migration is heterogeneous. One reason for this heterogeneity is the differential vulnerability of populations to climate change. This includes highly vulnerable, “trapped” populations that are too poor to migrate given deep and persistent poverty, the financial costs of migrating, and the erosion of already fragile economic livelihoods under climate change. Another reason for this heterogeneity is the differential vulnerability of places. However, despite the growing list of studies showing that the climate-migration relationship clearly varies across places, there is surprisingly little research on the characteristics of places themselves that trap, or immobilize, populations. Accordingly, we provide the first account of the “holding power” of places in the association between adverse climate conditions and migration flows among 55 districts in Zambia in 2000 and 2010. Methodologically, we combine high-resolution climate information with aggregated census micro data to estimate gravity models of inter-district migration flows. Results reveal that the association between adverse climate conditions and migration is positive only for wealthy migrant-sending districts. In contrast, poor districts are characterized by climate-related immobility. Yet, our findings show that access to migrant networks enables climate-related mobility in the poorest districts, suggesting a viable pathway to overcome mobility constraints. Planners and policy makers need to recognize the holding power of places that can trap populations and develop programs to support in situ adaptation and to facilitate migration to avoid humanitarian emergencies.
93 citations
TL;DR: It has become evident that deep African population history is captured by relationships among African hunter-gatherers, as the world's deepest population divergences occur among these groups, and that the deepest population divergence dates to 300,000 years before present.
Abstract: In the last three decades, genetic studies have played an increasingly important role in exploring human history. They have helped to conclusively establish that anatomically modern humans first ap...
71 citations
TL;DR: Davis et al. as discussed by the authors used a diffusion-based model of human mobility in combination with population, geographic, and climatic data to estimate the sources, destinations, and flux of potential migrants as driven by sea level rise (SLR) in Bangladesh in the years 2050 and 2100.
Abstract: Author(s): Davis, KF; Bhattachan, A; D'Odorico, P; Suweis, S | Abstract: Climate change is expected to impact the habitability of many places around the world in significant and unprecedented ways in the coming decades. While previous studies have provided estimates of populations potentially exposed to various climate impacts, little work has been done to assess the number of people that may actually be displaced or where they will choose to go. Here we modify a diffusion-based model of human mobility in combination with population, geographic, and climatic data to estimate the sources, destinations, and flux of potential migrants as driven by sea level rise (SLR) in Bangladesh in the years 2050 and 2100. Using only maps of population and elevation, we predict that 0.9 million people (by year 2050) to 2.1 million people (by year 2100) could be displaced by direct inundation and that almost all of this movement will occur locally within the southern half of the country. We also find that destination locations should anticipate substantial additional demands on jobs (594 000), housing (197 000), and food (783 × 109 calories) by mid-century as a result of those displaced by SLR. By linking the sources of migrants displaced by SLR with their likely destinations, we demonstrate an effective approach for predicting climate-driven migrant flows, especially in data-limited settings.
66 citations
TL;DR: A scaling model is developed which describes internal migration as a two-step decision process, demonstrating that it can partially explain migration fluxes based solely on city size, and shows that the scaling laws are a significant feature of human migration and that the inclusion of scaling can overcome the limits of the gravity and the radiation models ofhuman migration.
Abstract: Models of human migration provide powerful tools to forecast the flow of migrants, measure the impact of a policy, determine the cost of physical and political frictions and more Here, we analyse the migration of individuals from and to cities in the US, finding that city to city migration follows scaling laws, so that the city size is a significant factor in determining whether, or not, an individual decides to migrate and the city size of both the origin and destination play key roles in the selection of the destination We observe that individuals from small cities tend to migrate more frequently, tending to move to similar-sized cities, whereas individuals from large cities do not migrate so often, but when they do, they tend to move to other large cities Building upon these findings we develop a scaling model which describes internal migration as a two-step decision process, demonstrating that it can partially explain migration fluxes based solely on city size We then consider the impact of distance and construct a gravity-scaling model by combining the observed scaling patterns with the gravity law of migration Results show that the scaling laws are a significant feature of human migration and that the inclusion of scaling can overcome the limits of the gravity and the radiation models of human migration
54 citations
TL;DR: It is found that existing models of environment-migration linkages in rural contexts tend to not include fully integrated feedbacks and recommendations for the further development of ABMs are provided to contribute to an understanding of the environment-Migration-nexus in the future.
Abstract: Environmental change can lead to human migration and vice versa. Agent-based models (ABMs) are valuable tools to study these linkages because they can represent individual migration decisions of human actors. Indeed, there is an increasing, yet small, number of ABMs that consider the natural environment in rural migration processes. Therefore, we reviewed 15 ABMs of environment-migration linkages in rural contexts to synthesize the current state of the art. The reviewed ABMs are mostly applied in tropical contexts, serve a wide range of purposes, and cover diverse scales and types of environmental factors, migration processes, and social-ecological feedbacks. We identified potential for future model development with respect to the (1) complexity of environmental influence factors, (2) representation of relevant migration flows, and (3) type of social-ecological couplings. We found that existing models tend to not include fully integrated feedbacks and provide recommendations for the further development of ABMs to contribute to an understanding of the environment-migration-nexus in the future.
48 citations
TL;DR: P predictive machine learning models of human migration will provide a flexible base with which to model human migration under different what-if conditions, such as potential sea level rise or population growth scenarios.
Abstract: Human migration is a type of human mobility, where a trip involves a person moving with the intention of changing their home location. Predicting human migration as accurately as possible is important in city planning applications, international trade, spread of infectious diseases, conservation planning, and public policy development. Traditional human mobility models, such as gravity models or the more recent radiation model, predict human mobility flows based on population and distance features only. These models have been validated on commuting flows, a different type of human mobility, and are mainly used in modeling scenarios where large amounts of prior ground truth mobility data are not available. One downside of these models is that they have a fixed form and are therefore not able to capture more complicated migration dynamics. We propose machine learning models that are able to incorporate any number of exogenous features, to predict origin/destination human migration flows. Our machine learning models outperform traditional human mobility models on a variety of evaluation metrics, both in the task of predicting migrations between US counties as well as international migrations. In general, predictive machine learning models of human migration will provide a flexible base with which to model human migration under different what-if conditions, such as potential sea level rise or population growth scenarios.
44 citations
TL;DR: In recent times, high levels of human migration alongside the rapid development of the internet have increased the need to organize, perform, and experience festive family rituals as discussed by the authors, which can sustain relationships among family members.
Abstract: Organising, performing, and experiencing festive family rituals sustain relationships among family members. However, in recent times, high levels of human migration alongside the rapid development ...
38 citations
01 Jun 2018
TL;DR: In this article, the authors examined determinants of internal migration flows between the 21 provinces of Ecuador from 1982 to 2010 using specifications based on the gravity model, and identified push and pull factors.
Abstract: In this paper, we examine determinants of internal migration flows between the 21 provinces of Ecuador from 1982 to 2010. Using specifications based on the gravity model, we identified push and pull factors. We considered multilateral resistance to migration by using various monadic and dyadic fixed effects structures. The study confirmed the concentration of the population in the two provinces that contain the country's main cities. However, in recent years, this trend has weakened, to the extent that the provinces with the greatest influx of migrants are not necessarily the most populated. This indicates that growth has become more balanced throughout the territory, and that small and medium-sized cities are increasingly important.
TL;DR: In this article, the authors empirically show which factors -both individual characteristics and features related to the migration experience - influence the likelihood of a sub-optimal employment of returnees' human capital employing an original dataset on a representative sample of return migrants in Silesia (Poland).
Abstract: The existing economic literature focuses on the benefits that return migrants offer to their home country in terms of entrepreneurship, human and financial capital accumulation. However, return migration can have modest or even some detrimental effects if the migration experience was unsuccessful and/or if the migrant fails to reintegrate into the home country's economy. In our paper, we empirically show which factors - both individual characteristics and features related to the migration experience - influence the likelihood of a sub-optimal employment of returnees' human capital employing an original dataset on a representative sample of return migrants in Silesia (Poland).
TL;DR: A basic explanatory framework is proposed that highlights the linkages between these three dimensions and seeks to encourage debate, and new research, about how planetary health is concerned with, and within, this three-pronged nexus.
TL;DR: In this article, a framework is proposed to bridge some of the current fragmentation and knowledge hierarchies in the sociological field of migration, which is based on the insights of the authors of this paper.
Abstract: This introductory article outlines a framework to bridge some of the current fragmentation and knowledge hierarchies in the sociological field of migration. The article builds on the insights – and...
TL;DR: High maternal diversity and phylogenetic analyses suggest that the migrations post-Pleistocene were not strictly paternal, as described in the literature, and highlight the need for an extensive study of the endogamous populations of the region to unravel many facts and find links in the peopling of India.
Abstract: Jammu and Kashmir (J&K), the Northern most State of India, has been under-represented or altogether absent in most of the phylogenetic studies carried out in literature, despite its strategic location in the Himalayan region. Nonetheless, this region may have acted as a corridor to various migrations to and from mainland India, Eurasia or northeast Asia. The belief goes that most of the migrations post-late-Pleistocene were mainly male dominated, primarily associated with population invasions, where female migration may thus have been limited. To evaluate female-centered migration patterns in the region, we sequenced 83 complete mitochondrial genomes of unrelated individuals belonging to different ethnic groups from the state. We observed a high diversity in the studied maternal lineages, identifying 19 new maternal sub-haplogroups (HGs). High maternal diversity and our phylogenetic analyses suggest that the migrations post-Pleistocene were not strictly paternal, as described in the literature. These preliminary observations highlight the need to carry out an extensive study of the endogamous populations of the region to unravel many facts and find links in the peopling of India.
TL;DR: The results suggest a limited role of human migration in the emergence of agriculture in central Anatolia and a genetic link between southern Europe and the Near East predating 15,000 years ago that extends to central Europe during the post-last-glacial maximum period.
Abstract: Anatolia was home to some of the earliest farming communities. It has been long debated whether a migration of farming groups introduced agriculture to central Anatolia. Here, we report the first genome-wide data from a 15,000 year-old Anatolian hunter-gatherer and from seven Anatolian and Levantine early farmers. We find high genetic continuity between the hunter-gatherer and early farmers of Anatolia and detect two distinct incoming ancestries: an early Iranian/Caucasus related one and a later one linked to the ancient Levant. Finally, we observe a genetic link between southern Europe and the Near East predating 15,000 years ago that extends to central Europe during the post-last-glacial maximum period. Our results suggest a limited role of human migration in the emergence of agriculture in central Anatolia.
TL;DR: Zhang et al. as discussed by the authors adopted Push-Pull-Mooring (PPM) theory to explain the migration of human beings, where push is generated from people's dissatisfaction with their place of residence, pull is from attractions of the new environment, and personal mooring produces the intention of switching.
Abstract: Changes in the way people use information come from the concept of the most primitive human migration rule Scholars hold that migration can be considered as a switching of people’s place of residence, but the migration of people is not limited to the migration of residence The marketing field also borrows the population migration theory to further explore the switching behavior of customers; educationalists also discuss migration of learning through migration theory In this regard, the migration of human beings is a process of historical evolution, though it takes several decades to understand history from the perspective of such evolution Hence, if there is a decision-making system that simulates evolution and estimation through 3D graphics, then players may better understand the impact of environmental migration and changes on humanity This study adopts Push-Pull-Mooring (PPM) theory to explain the migration of human beings Push is generated from people’s dissatisfaction with their place of residence, Pull is from attractions of the new environment, and personal mooring produces the intention of switching A set of Gamification Environmental Education Applications (GEEA) and a migration scale for such apps are developed herein to explain the state where computer gamers switch to mobile app games The results show that all four hypotheses are supported, and the path coefficient of each hypothesis is highly significant The R2 values of five intrinsic constructs are Push (R2 = 0321), Mooring (R2 = 0574), Pull (R2 = 0413), Switching intention (SI) (R2 = 0552), and SB (R2 = 0626), where the R2 value of SB is quite high, indicating that the relationship between the switching behavior (SB) and the four precursors exhibits great explanatory power Hence, the explanatory power of this model is convincing, and the teaching materials designed through gamification education deliver better learning outcomes
TL;DR: In this article, the authors examined the trends, patterns, and determinants of Ethiopian domestic labor migration to Arab countries, concluding that the primary motivation behind migration is to move out of poverty and to improve family living standards through remittances.
Abstract: This paper examines the trends, patterns, and determinants of Ethiopian domestic labour migration to Arab countries. The primary motive behind migration is to move out of poverty and to improve family living standards through remittances. Migration to Arab countries has intensified due to social networks, expansion of illegal agencies, and the relative fall of migration costs. This movement is also the result of a shift in demand away from Asian domestic workers who tend to seek higher wages, to cheap labour source countries such as Ethiopia. This underlines not only the complexity of human mobility across national borders but also indicates the importance of conceptualising this movement in a broader global perspective, going beyond the traditional push-pull factors embedded in origin and destination countries. Female domestic migrants have received marginal attention from policy-makers and their vulnerability to various forms of abuse and exploitation has continued over the years.
01 Jan 2018
TL;DR: The authors examined the linkages between climate change and human movement with a view to encouraging more congenial migration and human development outcomes in South Asia, and developed recommendations in areas of poverty reduction, livelihood security, transitional education, and government planning.
Abstract: South Asia is one of the most densely settled and disaster-prone regions in the world. Furthermore, in many low-lying coastal contexts both slow-onset and rapid-onset natural disasters coalesce with existent conditions of poverty and vulnerability to progressively erode and compromise human adaptive capacity, resulting in a persistent flux of livelihood driven human migration into cities (A background video documentary to this research was published by UNSW Australia on 18 February 2015 and may be accessed at https://youtu.be/PBJeelgnadU). While climate change cannot be isolated as the definitive cause of this movement, it is impossible to dismiss it as a contributing factor. Lack of basic education plays a key role in limiting options for arriving daily wage labourers and their respective families, constraining many to struggle for subsistence survival in subhuman conditions in urban slums where vulnerabilities have been described as even more severe than the problems in rural communities of origin that triggered the migrations in the first place. Drawing on field research conducted in Bangladesh, this paper examines the linkages between climate change and human movement with a view to encouraging more congenial migration and human development outcomes. It extends previous research by expressly inviting the grassroots perspectives of rural communities of origin in Bhola Island and urban centres of destination in Dhaka and Chittagong. The research develops recommendations in areas of poverty reduction, livelihood security, transitional education, and government planning. Experiences and lessons gathered in this paper will be useful for both policy and practice serving the cause of climate change adaptation in South Asia.
TL;DR: The authors investigates international labour migration financing processes and related resource backwash -the flow of resources away from the migrant household which continue sometime after the in-turn of the migration process, which is referred to as backwash.
Abstract: This paper investigates international labour migration financing processes and related resource backwash – the flow of resources away from the migrant household which continue sometime after the in...
TL;DR: The purpose of this article is to describe current trends in international medical education and how this has motivated others to act to assure the quality of individual graduates and educational programs.
Abstract: The global healthcare market is massive and expanding and is having an unprecedented influence on medical education around the world.1 Increased demand for healthcare has created demand for physicians over and above the global shortage of physicians that has been well-recognized. This heightened demand for physicians has led to a number of trends, such as an exponential increase in the number of medical schools and medical students and migration for medical education and training.2-6 This new global medical education system, marked by its growing size and complexity, has led to greater concerns about quality assurance of individual graduates and their educational programs. The purpose of this article is to describe current trends in international medical education and how this has motivated others to act to assure the quality of individual graduates and educational programs.
International medical schools and migration of medical students
The number of medical schools around the world has been increasing dramatically over the last several decades, particularly in emerging economies, in response to legacies of physician shortages and the increased demand for healthcare. In some locations, such as India, Pakistan, China, and Brazil, this rapid growth is potentially beneficial to scaling up physician training and meeting population needs. However, in other locations, notably the Caribbean, there are far more medical schools than are needed to serve the local population. This asymmetric growth in medical schools is likely fostered by an increased willingness of individuals to travel for their medical education. While the “brain drain” of trained physicians from low income to high-income settings has been well-recognized, migration for undergraduate medical education is a growing trend. Medical education programs that are taught entirely in English have developed in non-English speaking countries, including those in Eastern Europe, Russia, Ukraine, and China, to attract international students and allow graduates greater mobility across European borders and entrance to practice in English-speaking areas.4-9 With the language barrier removed, students often seek these international medical schools as admission may be less competitive or tuition costs lower than schools in their home countries. Additionally, some schools, such as several in the Caribbean, have modeled and developed their admissions processes and curricula after US medical schools to attract international students.10
These different driving forces - the urge to seek medical education at lower cost and at institutions that have less competitive admissions processes have ushered in more complex patterns of migration than those of traditional “brain drain”. Generally, there has been a decrease in the number of international students opting to study in “resource-rich” countries,2,4 although many students still migrate from areas where medical education may not be possible. Currently, North America, South Asia, and Africa are the largest sending regions, and the Americas, Eastern Europe, China, and Russia are the most common receiving regions of international medical students worldwide.3,5,6,10 China provides an example of how student flows are taking new patterns. There, health professional students are currently the third largest group among all international students, with the largest influxes coming from South Asian and African countries.9
TL;DR: Both teams show that human migration was highly significant, especially the migration of mid-Holocene Neolithic farming populations, ∼5000 to 4000 years ago, from southern China into both mainland and island Southeast Asia.
Abstract: Anthropologists and prehistorians have debated the origins of the peoples of Southeast Asia for more than a century, often without consensus over the relative importance of successive migrations from external sources versus indigenous continuity through time. The analysis of ancient whole-genome DNA from archaeological skeletons brings a new view to this debate ( 1 , 2 ). On pages 88 and 92 of this issue, McColl et al. ( 3 ) and Lipson et al. ( 4 ), respectively, use genomic DNA sequencing data from 43 ancient Southeast Asian skeletons excavated by archaeologists to explain how the region was peopled during the past 10,000 years. Both teams show that human migration was highly significant, especially the migration of mid-Holocene Neolithic farming populations, ∼5000 to 4000 years ago, from southern China into both mainland and island Southeast Asia.
TL;DR: This paper analyzed the determinants of remittances sent while the migrants were abroad and found that the decision to remit and the amount remitted depend on a combination of different migrant characteristics and reasons for migration as well as the form of migration.
Abstract: This paper utilizes survey data of return migrants to analyze the determinants of remittances sent while the migrants were abroad. We approach our research question from the perspective of three sending countries in the Maghreb, namely Algeria, Morocco, and Tunisia. We investigate the remittance behavior using the migrants’ conditions before migration as well as during the migration experience. Using a two-part model, we show that the decision to remit and the amount remitted depend on a combination of different migrant characteristics and reasons for migration as well as the form of migration. More importantly, we also consider if the remittance behavior is dependent on the type of return: “decided” or “compelled.” We show that the two groups have different incentives to remit, which can help explain the link between type of migrants and their remittance behavior.
TL;DR: The study findings suggest that, given high symptom levels reported by both Burman and Karen refugees, health-care professionals ought to pay special attention to psychosomatic symptoms related to depression, anxiety, and PTSD, especially among Karen ethnic as well as female refugees from Burma.
Abstract: Despite representing the largest share of U.S. refugee resettlement in the past decade, we know very little about refugees from Burma or about their behavioral health problems. Current literature suggests that refugees likely suffer from depression, anxiety, posttraumatic stress disorder (PTSD), and alcohol use disorder. Using a subset of data from a community-based research project, we examined how sociodemographic and migration-related factors are associated with behavioral health outcomes among two major ethnic groups of refugees from Burma, namely, the Burman (n = 84) and the Karen (n = 100) ethnic people. Four behavioral health outcome variables were examined: Symptoms of depression and anxiety were assessed with the Hopkins Symptom Checklist, PTSD symptoms with the Refugee Health Screener-15, and alcohol use disorder symptoms with the Alcohol Use Disorder Identification Test. Univariate analyses described sociodemographic, migration-related, and behavioral health characteristics by Burman and Karen groups. Multivariate linear regressions were then conducted to examine associations between sociodemographic and migration-related factors with four outcome variables. Results revealed that sociodemographic (ethnicity, sex, and education) and migration-related (length of camp stay and English proficiency) factors are significantly and consistently associated with one or more outcome variables. The study findings suggest that, given high symptom levels reported by both Burman and Karen refugees, health-care professionals ought to pay special attention to psychosomatic symptoms related to depression, anxiety, and PTSD, especially among Karen ethnic as well as female refugees from Burma.
01 Jan 2018
TL;DR: In this article, the authors explore the patterns and drivers of migration within the lifetime of those currently alive and investigate how this influences forest conversion on the border of established protected areas and sites without a history of conservation restrictions.
Abstract: Human migration is often considered an important driver of land use change and a threat to protected area integrity, but the reasons for in-migration, the effectiveness of conservation restrictions at stemming migration, and the extent to which migrants disproportionately contribute to land use change has been poorly studied, especially at fine spatial scales. Using a case study in eastern Madagascar (603 household surveys, mapping agricultural land for a subset of 167 households, and 49 focus group discussions and key informant interviews), we explore the patterns and drivers of migration within the lifetime of those currently alive. We investigate how this influences forest conversion on the border of established protected areas and sites without a history of conservation restrictions. We show that in-migration is driven, especially in sites with high migration, by access to land. There is a much higher proportion of migrant households at sites without a long history of conservation restrictions than around long-established protected areas, and migrants tend to be more educated and live closer to the forest edge than non-migrants. Our evidence supports the engulfment model (an active forest frontier later becoming a protected area); there is no evidence that protected areas have attracted migrants. Where there is a perceived open forest frontier, people move to the forest but these migrants are no more likely than local people to clear land (i.e., migrants are not “exceptional resource degraders”). In some parts of the tropics, out-migration from rural areas is resulting in forest regrowth; such a forest transition is unlikely to occur in Madagascar for some time. Those seeking to manage protected areas at the forest frontier will therefore need to prevent further colonisation; supporting tenure security for existing residents is likely to be an important step.
TL;DR: This study uses aggregate location-aware data collected from mobile location requests in the largest Chinese social media platform during the period of the 2016 Chinese New Year to conduct a nationwide estimate of rural depopulation in China (in terms of the grid cell-level prevalence and the magnitude) based on the world’s largest travel period.
Abstract: The rapidly developing economy and growing urbanization in China have created the largest rural-to-urban migration in human history. Thus, a comprehensive understanding of the pattern of rural flight and its prevalence and magnitude over the country is increasingly important for sociological and political concerns. Because of the limited availability of internal migration data, which was derived previously from the decennial population census and small-scale household survey, we could not obtain timely and consistent observations for rural depopulation dynamics across the whole country. In this study, we use aggregate location-aware data collected from mobile location requests in the largest Chinese social media platform during the period of the 2016 Chinese New Year to conduct a nationwide estimate of rural depopulation in China (in terms of the grid cell-level prevalence and the magnitude) based on the world’s largest travel period. Our results suggest a widespread rural flight likely occurring in 60.2% (36.5%-81.0%, lower-upper estimate) of rural lands at the grid cell-level and covering ~1.55 (1.48–1.94) million villages and hamlets, most of China’s rural settlement sites. Moreover, we find clear regional variations in the magnitude and spatial extent of the estimated rural depopulation. These variations are likely connected to regional differences in the size of the source population, largely because of the nationwide prevalence of rural flight in today’s China. Our estimate can provide insights into related investigations of China’s rural depopulation and the potential of increasingly available crowd-sourced data for demographic studies.
TL;DR: The simulations showed that in the new cities, nationality segregation levels are expected to drop by at least 15% compared to the 2015 levels, and the findings may be utilised by the authorities to modify the master plan accordingly.
Abstract: Modelling of internal migration to new cities is challenging, yet necessary to ensure that these newly established urban areas will be populated and function as intended. In the State of Kuwait, there is a unique set of push and pull factors: government subsidised housing for citizens, the existence of a single urban area, and the initiation of a new and ambitious master plan for the construction of 12 new cities, which are expected to attract not only locals, but also international residents and businesses. On top of these factors, there is an unusual demographic situation, as non-citizens outnumber Kuwaiti citizens by a factor of 2.3, with these groups having widely different preferences in terms of housing. Currently, there is no plan to take these resident groups' opinions into consideration for the new cities project. Besides, the current study simulates the impacts of the involvement of residents in urban planning. Samples from resident groups (citizens and non-citizens) participated in targeted surveys and useful answers were extracted in relation to the migration likelihood, push and pull factors that may affect their decisions, spatial preferences for new cities and their opinions on segregation by nationality. Specifically, the survey results showed significant interest of residents in moving to the new cities. For citizens, the most important factors in deciding whether to move or not were proximity to their close family and housing availability, while for non-citizens the most important factor was the creation of new employment opportunities. Both survey groups agreed that existing city property prices are too high and make the prospect of moving to a new city more attractive. The responses were transferred in an Agent Based Model, and the simulations showed certain differences to the official projections for 2050 without the public responses, in regards to the geographical distribution of the most desirable suburbs. Furthermore, the simulations showed that in the new cities, nationality segregation levels are expected to drop by at least 15% compared to the 2015 levels. The findings may be utilised by the authorities to modify the master plan accordingly.
TL;DR: Japan should focus on activating its human capital through the prolongation of working lives, increasing participation, and improving productivity within the Japanese labour force to mitigate and adapt to the inevitable effects of ageing populations.
Abstract: Japan’s ongoing struggle with rapid ageing is well known. Fertility and migration policies have both been proposed as solutions to Japan’s ageing population. We used stock flow population models to estimate the impact of hypothetical fertility and migration policy interventions on measures of aging in Japan from 2015 to 2050. We evaluated policy models based on the Old Age Dependency Ratio (OADR) they produced at the specified end date. Start dates ranged from 2020 to 2030 to assess the time horizons of individual policies. Fertility policies were found to be highly time dependent and only slowed the rate of increase of OADR. It would require a Total Fertility Rate far above replacement levels to compensate for Japan’s already aged demography. Migration policy was less time dependent. However, such measures would require unprecedented, and ultimately unrealistic, volumes of migration over coming decades in order to reduce Japan’s OADR. Our results suggest that fertility and migration based policy responses will be unable to significantly reduce Japan’s OADR or reverse Japan’s ageing population within the next few decades. Japan should focus on activating its human capital through the prolongation of working lives, increasing participation, and improving productivity within the Japanese labour force to mitigate and adapt to the inevitable effects of ageing populations.
TL;DR: An evolutionary and ecological framework is developed to explain various movement behaviours and this framework is applied to the movement of human groups from the inter-visible islands around New Guinea to the widely dispersed archipelagos of the southwest Pacific about 1000 BC.
Abstract: Migrations have occurred across the history of the genus Homo and while the movement of pre-modern humans over the globe is typically understood in terms of shifting resource distributions and climate change, that is in ecological terms, the movement of anatomically modern, and specifically Holocene, populations is often explained by human desire to discover new lands, escape despotic leaders, forge trade relationships and other culture-specific intentions. This is a problematic approach to the archaeological and behavioural explanation of human migration. Here an evolutionary and ecological framework is developed to explain various movement behaviours and this framework is applied to the movement of human groups from the inter-visible islands around New Guinea to the widely dispersed archipelagos of the southwest Pacific about 1000 BC. Labelled the Lapita Migration, this movement is explained as a selection-driven range expansion. The development of evolutionary and ecological theory to explain human movement facilitates empirical testing of alternative hypotheses and links different histories of human movement through shared explanatory mechanisms.
TL;DR: In the early twenty-first century (2000-2015), internal migration has been recognized as the major influence in terms of population redistribution across urban systems, but it is not a homogeneous phenomenon.
Abstract: Internal migration has been recognized as the major influence in terms of population redistribution across urban systems, but it is not a homogeneous phenomenon. Within the context of internal rural-urban migration decline and the negative changes in migratory balances in the metropolitan area of Mexico City, the core of enquiry in this paper is the approach to growth and consolidation of an internal urban–urban migration system in the early twenty-first century (2000–2015). This process has taken place through two main networks, among metropolitan areas not corresponding to the principal city and among intermediate cities. Internal migration is a complex process that involves both individual and spatial characteristics and which leads to spatially uneven development in the long term. Data from three censuses of the population of Mexico (2000, 2010, and 2015) show a transition to a more urban–urban migration pattern, with skilled migrants tending to have metropolitan and urban destinations, whereas less-skilled migrants prefer rural and small urban destinations.