Margaret Corley

The Asian tiger mosquito (Aedes albopictus) is an invasive species that has become widespread throughout the Americas. It is a vector for several arboviruses, making it an increasing threat to human health as its range expands. To characterize population genetic structure and gain insight into the origin and spread of this invasive mosquito, we genotyped 959 individuals using ~20k SNPs. We included 50 localities across the Americas, and previously genotyped mosquitoes from 28 localities in Asia and 14 in Europe. Our analyses revealed that populations in North America were distinct from populations in South America, and this relationship was consistently supported across analyses. Most North American mosquitoes shared a common origin with those from Japan and Southern Europe (e.g., Italy, Spain), with the exception of individuals from California, which clustered with more southern areas of East Asia (China and Vietnam), as well as Greece. Brazilian and Argentinian populations were distinct from all other sampled locations, including those in the native range, but were most closely related to mosquitoes from more tropical locations in South and Southeast Asia. By revealing the likely sources of invasions in the Americas, our findings have important implications for understanding invasion dynamics of this species.

In this exploratory study, we analyzed the hormonal and growth trajectories of 61 Qom/Toba girls aged 8 to 14 years from a peri-urban community in Formosa, Argentina. Monthly measurements of weight and height were taken, and eight urine samples were collected every three months until the menarche was reported or until the end of the study. The urine samples were analyzed using enzyme immunoassay to determine testosterone and C-peptide levels. Bayesian Gompertz models were used to generate predicted hormonal and anthropometric growth parameters for statistical analysis. The model results suggest that early menarche and a higher overall body mass index (BMI) velocity during puberty were associated with rapid increases in C-peptide levels in the early stages of puberty but not with higher initial levels of these variables. It was predicted that most girls would maintain their initial BMI status throughout puberty while 10% would transition from overweight to a healthy weight, and 15% from healthy weight to overweight or obesity. Neither predicted adult height nor growth velocity showed a statistically significant association with BMI velocity, although growth velocity was positively correlated with C-peptide and testosterone levels up to age 11. These f indings underscore the importance of longitudinal data in understanding the heterogeneous patterns of pubertal growth and obesity risks within and across populations.

Characterizing patterns of genetic diversity and gene flow is crucial for understanding the movements of dispersing individuals, and for assessing population viability and informing conservation strategies. The South American Gran Chaco is one of the most threatened ecosystems in the Americas. Yet critical data on the population genetic structure for many mammals occupying this ecoregion, including primates such as Azara's owl monkey (Aotus azarae), are lacking. We used 22 microsatellite loci and mitochondrial DNA sequences to assess genetic diversity and population structure in A. azarae, an arboreal, pair‐living platyrrhine primate, in the Gran Chaco of northern Argentina in areas characterized by a contiguous gallery forest and patches of forest in naturally occurring savanna. We also analyzed sex‐specific patterns of isolation‐by‐distance and used assignment tests to evaluate dispersal patterns, assess potential sex differences in gene flow, and assessed potential differences in gene flow within and between gallery forest and forest patch habitats. We found limited genetic structure within sampling locations, and a moderate level of genetic differentiation between the two most‐distant regions. There was no evidence of genetic differentiation between habitat types (gallery vs. forest patches). Some analyses suggest greater dispersal by females than males, although the evidence is not strong. We integrated these results with previous demographic and behavioral observations gathered since 1996 as part of a long‐term study of owl monkeys in this area. This study constitutes an important first step in characterizing the genetic structure and patterns of gene flow for Azara's owl monkey populations in Argentina, which is essential for combatting the effects of habitat loss and fragmentation on these native populations and for informing conservation management strategies for pair‐living primates throughout the South American Gran Chaco.

The Asian tiger mosquito, Aedes albopictus, is currently the most widespread invasive mosquito species in the world. It poses a significant threat to human health, as it is a vector for several arboviruses. We used a SNP chip to genotype 748 Ae. albopictus mosquitoes from 41 localities across Europe, 28 localities in the native range in Asia, and 4 in the Americas. Using multiple algorithms, we examined population genetic structure and differentiation within Europe and across our global dataset to gain insight into the origin of the invasive European populations. We also compared results from our SNP data to those obtained using genotypes from 11 microsatellite loci (N = 637 mosquitoes from 25 European localities) to explore how sampling effort and the type of genetic marker used may influence conclusions about Ae. albopictus population structure. While some analyses detected more than 20 clusters worldwide, we found mosquitoes could be grouped into 7 distinct genetic clusters, with most European populations originating in East Asia (Japan or China). Interestingly, some populations in Eastern Europe did not share genetic ancestry with any populations from the native range or Americas, indicating that these populations originated from areas not sampled in this study. The SNP and microsatellite datasets found similar patterns of genetic differentiation in Europe, but the microsatellite dataset could not detect the more subtle genetic structure revealed using SNPs. Overall, data from the SNP chip offered a higher resolution for detecting the genetic structure and the potential origins of invasions.

Natal dispersal is an important life-history stage influencing individual fitness, social dynamics of groups and population structure. Understanding factors influencing dispersal is essential for evaluating explanations for the evolution and maintenance of social organization, including parental care and mating systems. The social and mating systems of Azara’s owl monkeys ( Aotus azarae ) are infrequent among mammals; these primates are pair-living, serially and genetically monogamous and both sexes directly care for offspring. To evaluate the role that competition and inbreeding avoidance play in shaping dispersal patterns, we used 25 years of demographic and genetic data to examine how variation in timing of natal dispersal is related to social (adult replacements, step-parents, births and group size) and ecological factors (seasonal abundance of resources) in a wild population of A. azarae in Formosa, Argentina. We found that all males and females dispersed from their natal groups, but subadults delayed dispersal when a step-parent of the opposite sex joined the group, indicating that they may perceive these step-parents as potential mates. Dispersal was more probable when resource conditions were better, regardless of age. Overall, agonistic conflict over food and potential mates with adults in the natal group, as well as inbreeding avoidance, contribute to regulating dispersal.

Olfactory behaviors serve a wide variety of social functions in mammals. Odor may signal information about attributes of individuals important for mating and reproduction. Olfactory behaviors, such as scent‐marking, may also function as part of home range or resource defense strategies. We assessed the potential social and home range defense functions of olfactory behavior in a pair‐living and sexually monogamous primate, Azara's owl monkey (Aotus azarae), in the Argentinian Chaco. This is the most extensive investigation of owl monkey olfactory behaviors in the wild. Individuals regularly performed olfactory behaviors (group mean + SD = 1.3 + 0.5 per hour). The patterns were generally comparable to those observed in studies of captive owl monkeys, except that urine washing was the most common behavior in the wild, as opposed to scent‐marking and genital inspections. Most olfactory behaviors were performed by adults, and there were striking sex differences in genital inspections: almost all consisted of an adult male inspecting the paired adult female. These findings suggest that olfactory behaviors play an important role in signaling and coordinating reproduction among owl monkeys, particularly during periods of female conception and pregnancy. Additionally, our research indicates that these behaviors may also serve as a defense strategy for maintaining the core area of their home ranges. This study offers the first assessment of the role of olfactory behaviors in reproductive contexts and home range defense in pair‐living, monogamous platyrrhine primates.