Articles tagged with Population Dynamics
Researchers Dean Falk and Charles Hildebolt question the idea that larger populations are less prone to violence. Contrary to Steven Pinker's theory, they found that war deaths scale similarly with population sizes across all levels of human society.
A new study analyzes Google Trends data across eight countries, finding summer and fall seasons correlate with greater hair loss. The findings provide evidence for seasonality in hair loss at a population level, supporting future research into the physiology of the hair cycle.
A new mathematical model has been developed to analyze the relationship between population migration and living standards. The study found that wealth distribution is closely tied to population dynamics, with resources flowing from developed countries to poor regions through trade and investment.
A new statistical model confirms a decline in North Atlantic right whale population since 2010, with adult females experiencing a significant drop. The study's findings highlight the need for urgent conservation efforts to protect this endangered species.
A new study from Penn State found that more educated individuals are early adopters of risky behaviors and set trends for others to follow. However, once informed about the health risks, they quickly adjust their habits, making them potential trendsetters for positive change.
Researchers used algae modeling to study competing ideologies and their survival rates. They found that a balance between offensive and defensive strategies is key, with a 50-50 mix being the most effective.
A study found that green anole lizards in the south developed greater resistance to cold temperatures after a severe winter, similar to their northern counterparts. The population showed significant genetic divergence in response to the extreme weather event.
By the late 21st century, South Asia is projected to experience deadly heat waves, with wet-bulb temperatures surpassing human survivability limits. Climate change mitigation efforts could reduce population exposure by up to 70%, according to new research.
A new study predicts population aging will peak before the end of the century in China and Germany, with the US experiencing little aging. Traditional projections underestimate the impact of increasing life expectancy on age structures.
A new continuous-discrete hybrid population model describes the invasive dynamics of zebra mussels in North American rivers. The model shows that population persistence is contingent upon moderate water temperatures and low flow velocities, and that upstream invasion success depends on these factors.
A new study by San Diego State University suggests that lysogeny, where viruses lie dormant within host cells, may be more prevalent under stressful environmental conditions. This finding has significant implications for understanding degraded coral reef ecosystems and preserving them.
A new study reveals that fishing can lead to massive gene expression changes in an exploited fish population, affecting their ability to adapt. Removing the largest individuals from a population induces differences in thousands of genes, which persist even after recovery.
A comprehensive population assessment of Chinese white dolphins in Hong Kong waters reveals a significantly higher number than previously reported. The study used photographic mark-recapture technique to estimate the overall number of dolphins using Hong Kong waters during the study period.
Researchers used financial math models to accurately predict changes in HIV surface proteins over 30 years. By analyzing structural properties and 'volatility,' they can design vaccines that match the virus's evolving targets.
Research suggests that biodiversity is linked to lower infectious disease prevalence in people, contradicting concerns that intact ecosystems pose a danger. However, animal species do not present an equal threat of disease transmission, and some families like rodents transmit disease more commonly than others.
Research found that higher levels of grazing early in the growing season decline sage-grouse population trends, while similar levels of grazing later in the season correspond with increases. Grazing management actions can positively affect sage-grouse populations by increasing food resources and nesting cover.
The discovery of two partial archaic human skulls from the Lingjing site in central China reveals a complex mix of biological trends among early modern humans. The fossils, dated to around 100,000 years ago, show a blend of features with late archaic and early modern humans, as well as Neandertals.
A new study finds that all but one coastal shark species are increasing in abundance, following decades of declining numbers. The gains are attributed to the enactment of fishing regulations in the early 1990s.
Climate change is driving population migration, particularly in Arctic Alaska, where rising temperatures and thawing permafrost pose significant threats. Lawrence Hamilton's research uses annual migration data to shed light on the climate contribution to this phenomenon.
A new study finds that beluga whales in Alaska are mirroring changes in Arctic sea ice timing, delaying their migration south by up to one month. However, another population remains unaffected by these changes, suggesting variability in response across populations and time.
Research finds small populations of little brown bats in New York have lower infection levels, suggesting host resistance to white-nose syndrome. This is good news for some bat colonies, but other species show no sign of being able to persist with the disease.
Long-term datasets show mosquito populations increased ten-fold in NY, NJ, and California over the past five decades. Urbanization and residual DDT concentrations drove these changes, contrary to initial expectations linked to climate change.
A model developed at Michigan State University shows how barred owls are dominating northern spotted owl territories and outcompeting them for resources. The model, called Dynamic N-occupancy, uses simple data on species presence to provide accurate estimates of local abundance and population growth.
A study investigated infectious disease mortality trends in the US from 1980 to 2014, revealing overall and infectious disease mortality decreased until 1995, then leveled off. The introduction of antiretroviral therapy for HIV/AIDS led to a decline in overall and HIV/AIDS mortality rates.
Researchers found that extreme heat during pupal life stages is detrimental to over half of UK species, while precipitation can be detrimental to up to a quarter. However, some life stages may benefit from climatic extremes, with warm summers causing positive population changes in over one-third of the UK species.
The universal two-child policy is predicted to have a relatively small effect on population growth, with a peak of 1.45 billion by 2029. However, it may lead to changes in retirement age and pension systems to address shrinking workforce and population ageing.
A University of Adelaide study found that warmer waters and higher CO2 levels can lead to a twenty-fold increase in the population of a common marine crustacean. Males become larger and more attractive to females, resulting in a massive population explosion.
Researchers found that older Whooping cranes are leading the way in changing migration patterns due to climate and land use change. The birds' long-term memory and ability to learn from experience enable them to innovate new behaviors, such as shortstopping, which involves shifting wintering grounds closer to breeding grounds.
Researchers found that bird species with increasing populations occupy a broader range of climate conditions, while declining species lose their range. This discovery has practical applications for conservation biologists, who can use the new findings to develop more accurate habitat protection strategies.
A study of Minnesota patients found a possible increase in Parkinson's disease and parkinsonism cases between 1976 and 2005, particularly in older men. The trends may be associated with decreased smoking rates over the decades.
Statisticians at the University of Washington have developed a probabilistic model that incorporates global migration patterns to project populations worldwide. The study challenges existing predictions for countries like Germany and the US, predicting a larger population in Germany if immigration continues and a 10% chance of exceedin...
Researchers use diffusion equation and geographical data to simulate prehistoric human migration into England, Scotland, and Wales. The method accurately predicts points of contact between migratory paths, providing insights into early human dynamics.
Current whale migration models are too simplistic and don't account for the complexity of their ecological behavior. A deeper understanding of factors like reproductive patterns and local adaptations is needed to understand the diversity of migratory habits in baleen whales.
Researchers from NYU and Duke University found that 80% of Americans live in counties with more favorable weather conditions since the 1970s. However, future climate change projections suggest that nearly 90% of the US public will experience less pleasant weather by the end of the century due to rising temperatures.
A 20-year study found a significant drop in dementia incidence among men in the UK, driven by reduced risk factors such as smoking and improved vascular health. The study suggests that targeted public health measures may help prevent future increases in dementia cases, contradicting global projections of a looming 'dementia tsunami'.
A study by Durham University found that climate change is having a similar impact on common bird populations worldwide. Species favored by changing climates outperformed those disadvantaged by warming trends over a 30-year period from 1980 to 2010.
A study of over 15,000 people found a 10% rise in older adults developing second or third chronic conditions, while physically active individuals were healthier. The prevalence of multimorbidity increased from 31.7% to 43.1% between 2002/03 and 2012/13.
A study confirms that a Thai sanctuary is the only site in Southeast Asia where tigers are increasing in number. The sanctuary's tiger population has recovered thanks to enhanced protection measures and intensive patrol systems, which have led to improved survival and recruitment rates among the iconic carnivores.
A study found that ocean acidification can lead to genetic drift in populations, hindering adaptation to climate change. The researchers observed changes in shell length and sex ratio, as well as increased metabolic rates, in response to acidic waters.
A global analysis reveals that intentional killing by humans is a major cause of bat mortality, but collisions with wind turbines and white-nose syndrome are now leading causes. Climate change is expected to increase mortality from storms and other abiotic factors.
Researchers used game theory to model the dynamics of farmer decisions and their effects on pest populations. The study found that farmers' perceptions of profit and loss, as well as communication networks, can influence pest control strategies.
A new international study developed a framework to explain Earth's diverse plant growth forms, functions, and ecological roles. The framework predicts plant population responses to environmental change, offering insights into land recovery projects.
The study found that the net fiscal redistribution from the non-refugee population to refugees in Sweden corresponded to 1.0 percent of Swedish GDP in 2007. This is due to lower public per capita revenues from refugees compared to the total population, largely attributed to their lower employment rate.
Researchers found that winter temperatures drive synchrony in aphid flight timings, affecting commercial crops like alfalfa and wheat. Climate change influences spatial synchrony in many species, with implications for public health and commercial endeavors.
A new study finds that malaria risk in Africa is shifting due to climate change, with the highest-risk transmission zone moving eastward and expanding into new areas by 2080.
The PLOS Genetics Research Prize 2015 was awarded to Barroso-Batista et al. for their study on the adaptation of E. coli to the gut, which found that clonal interference dominates early stages of adaptation. The research used mice as hosts and demonstrated high reproducibility in populations evolving in different mice.
A new study by researchers from Linnaeus University demonstrates that a higher degree of individual variation is beneficial to populations and species. The findings suggest that more variable populations are less vulnerable to environmental changes, show decreased fluctuations in population size, have superior establishment success, la...
A new study found that older populations in Germany and England are scoring better on cognitive tests, while physical functioning and mental health have declined. The increasing use of modern technology and higher education levels contribute to the improvement in cognitive abilities.
The prevalence of overweight and obesity decreased in Greek schoolchildren, while normal weight children increased, during the early years of the Greek economic crisis. This change may be attributed to suboptimal living conditions during that period.
A new study published in the International Journal of Environmental Research and Public Health highlights the public health implications of climate change on the US Gulf Coast, Northeast, and West Coast. The research emphasizes the need for simultaneous mitigation and adaptation strategies to address the growing threats.
A new model suggests that wealthy countries' ability to mitigate flood risks through investments will be unsustainable in the long term. As a result, they may experience similar flood risk levels as developing countries.
A new study provides the first detailed view of calling blue and fin whale distribution in Southern California, revealing a steady population trend for blue whales and an upward trend for fin whales. The research uses acoustic data collected from 2006-2012, indicating that fin whales are more likely to be detected further offshore.
Research published in Tobacco Control found that including experimenters in e-cigarette prevalence studies can lead to inaccurate results. The study suggests setting a threshold of six days out of the past 30 for more accurate monitoring of population health trends. Current smokers were more likely to use e-cigarettes than former or ne...
A new study projects that US residents' exposure to extreme heat could increase four- to six-fold by mid-century, driven by both a warming climate and a growing population. The research found that the average annual exposure to extreme heat in the US during this period is expected to be between 10 and 14 billion person-days.
A study finds that the global food system is becoming more fragile and susceptible to crisis as population growth increases and international trade expands. Countries heavily reliant on imports face greater instability and food insecurity, exacerbating existing challenges.
Research by University of Montreal demographers reveals that socio-economic inequalities among First Nations communities drive migration patterns in Canada. Main reasons for migration include pursuing education, finding work, and seeking better health and living conditions.
A report by University of Montreal researcher Yves Carrière finds that delaying retirement eligibility will widen disparities among older adults. This policy change is expected to disproportionately affect those with lower incomes, who will be more reliant on private savings for support.
The Canadian population aged 85 and over has grown to 702,000 by 2013, representing 2% of the total population. As the 'oldest old' category continues to evolve, it will impact public policy and require distinct services.
Research suggests that immigrant health policies should be tailored to individual groups, taking into account age and health indicators. A comprehensive review of 75 studies found that new immigrants have a healthier profile than the general population, but this advantage diminishes over time.
A new study published in CMAJ reports that the Rowland Universal Dementia Assessment Scale (RUDAS) is effective in assessing cognitive impairment in multicultural populations where English may not be the primary language. The tool has been shown to identify cognitive impairment and rule it out with strong psychometric properties, makin...