Artificial intelligence enables unified analysis of historical and landscape influences on genetic diversity.

While genetic variation in any species is potentially shaped by a range of processes, phylogeography and landscape genetics are largely concerned with inferring how environmental conditions and landscape features impact neutral intraspecific diversity. However, even as both disciplines have come to utilize SNP data over the last decades, analytical approaches have remained for the most part focused on either broad-scale inferences of historical processes (phylogeography) or on more localized inferences about environmental and/or landscape features (landscape genetics). Here we demonstrate that an artificial intelligence model-based analytical framework can consider both deeper historical factors and landscape-level processes in an integrated analysis. We implement this framework using data collected from two Brazilian anurans, the Brazilian sibilator frog (Leptodactylus troglodytes) and granular toad (Rhinella granulosa). Our results indicate that historical demographic processes shape most the genetic variation in the sibulator frog, while landscape processes primarily influence variation in the granular toad. The machine learning framework used here allows both historical and landscape processes to be considered equally, rather than requiring researchers to make an a priori decision about which factors are important.

The Demographic Drivers of Grief and Memory After Genocide in Guatemala.

Mortality crises are relatively common demographic events, but we know little about how they affect local populations beyond excess mortality. I argue that using a kinship perspective to study mortality crises provides valuable insights into (1) how excess mortality affects the exposure to kin loss and (2) how family bereavement may contribute to the reproduction of historical memory in the long term. I explore these two processes using a unique genealogical database that records the complete demographic history of Rio Negro, a genocide-affected population in Guatemala, between 1982 and 2015. The analysis shows that deaths from the 1982 genocide were balanced by age, sex, and socioeconomic status. One third of the population were killed, but two thirds were left bereaved (the top 10% most affected individuals lost 30% of their nuclear family relatives and 23% of their extended family relatives). Notably, the proportion of the population related to a victim did not change between 1983 and 2015. The persistence of family bereavement can be interpreted as a prolongation of grief or as a driver of historical memory. These demographic dynamics have implications for the study of historical events beyond mortality crises.

Quantifying the severity of hurricanes on extinction probabilities of a primate population: Insights into "Island" extirpations.

Long-term studies quantifying impacts of hurricane activity on growth and trajectory of primate populations are rare. Using a 14-year monitored population of Alouatta palliata mexicana as a study system, we developed a modeling framework to assess the relative contribution of hurricane disturbance and two types of human impacts, habitat loss, and hunting, on quasi-extinction risk. We found that the scenario with the highest level of disturbance generated a 21% increase in quasi-extinction risk by 40 years compared to scenarios of intermediate disturbance, and around 67% increase relative to that found in low disturbance scenarios. We also found that the probability of reaching quasi-extinction due to human disturbance alone was below 1% by 40 years, although such scenarios reduced population size by 70%, whereas the risk of quasi-extinction ranged between 3% and 65% for different scenarios of hurricane severity alone, in absence of human impacts. Our analysis moreover found that the quasi-extinction risk driven by hunting and hurricane disturbance was significantly lower than the quasi-extinction risk posed by human-driven habitat loss and hurricane disturbance. These models suggest that hurricane disturbance has the potential to exceed the risk posed by human impacts, and, in particular, to substantially increase the speed of the extinction vortex driven by habitat loss relative to that driven by hunting. Early mitigation of habitat loss constituted the best method for reducing quasi-extinction risk: the earlier habitat loss is halted, the less vulnerable the population becomes to hurricane disturbance. By using a well-studied population of A. p. mexicana, we help understand the demographic impacts that extreme environmental disturbance can trigger on isolated populations of taxa already endangered in other systems where long-term demographic data are not available. For those experiencing heavy anthropogenic pressure and lacking sufficiently evolved coping strategies against unpredictable environmental disturbance, the risk of population extinction can be exacerbated.

Ageing of Jamaica's population - What are the implications for healthcare? / Envejecimiento de la población de Jamaica. ¿Cuáles son las implicaciones para la atención de la salud?

The 2011 Census has confirmed the ageing of the Jamaican population. The over 60-year old population has increased while the under 15-year old population has decreased. Other demographic changes of note include the largest increase being in the old-old who are predominantly female. The demographic changes when considered with the increase in chronic disease indicate the need for consideration of healthcare specifically targeting the needs for older persons including increased prevention, continuous medical management, long term care and caregiver support.

El censo de 2011 ha confirmado el envejecimiento de la población jamaicana. La población de más de 60 años de edad ha aumentado, mientras que la población por debajo de 15 años ha disminuido. Otros cambios demográficos notables incluyen un mayor aumento en el grupo de los ancianos mayores de 85 años, predominantemente femenino. Los cambios demográficos considerados junto con el aumento de las enfermedades crónicas indican la necesidad de tener en cuenta una atención de la salud dirigida específicamente a las necesidades de las personas mayores, que incluya mayor prevención, tratamiento médico continuo, así como apoyo a largo plazo a los cuidados y a los cuidadores de la salud.