Composition of nests constructed by species in the Motacillidae, Sylviidae and Prunellidae

Bird nests can be complex bio-engineered structures constructed from a range of materials to provide a site for incubation, and in many species chick rearing. Reports of the materials used in nest walls and cup linings are typically qualitative and do not assist in understanding the functional properties of the structure as a whole. This paper provides size and composition data for nests from four species of the Motacillidae family: the meadow pipit ( Anthus pratensis), pied wagtail ( Motacilla alba), grey wagtail ( Motacilla cinerea), and the yellow wagtail ( Motacilla flava), three species of the Sylviidae family: willow warbler ( Phylloscopus trochilus), Eurasian reed warbler ( Acrocephalus scirpaceus) and Eurasian blackcap ( Sylvia atricapilla), and the dunnock ( Prunella modularis) of the Prunellidae family. Three hypotheses were tested: do nest dimensions correlate with body mass? Is it possible to distinguish among species based on their nest composition; and for individual species? Is it possible to distinguish between the cup lining and outer nest wall based on the materials used in construction? Nest composition and size varied among species although the degree of intra-specific variation was different. Size of a nest was unrelated to average female adult body mass. Composition relied on similar types of materials but in differing quantities between species. It was possible to distinguish among species in terms of nest construction, and between the cup lining and the outer nest, on the basis of at least one of the component materials. By providing quantitative data on composition, it may be possible in the future to understand better the structural, insulative and hydrological properties of the nest. Such information will be invaluable as we begin to develop an understanding of the factors that have driven evolution of nest architecture.

Parental provisioning drives brain size in birds

Larger brains should be adaptive because they support numerous eco- and socio-cognitive benefits, but these benefits explain only a modest part of the interspecific variation in brain size. Notably underexplored are the high energetic costs of developing brains, and thus the possible role of parental provisioning in the evolution of adult brain size. We explore this idea in birds, which show considerable variation in both socio-ecological traits and the energy transfer from parents to offspring. Comparative analyses of 1,176 bird species show that the combination of adult body mass, mode of development at hatching, relative egg mass, and the time spent provisioning the young in combination strongly predict relative brain size across species. Adding adult eco- and socio-cognitive predictors only marginally adds explanatory value. We therefore conclude that parental provisioning enabled bird species to evolve into skill-intensive niches, reducing interspecific competition and consequently promoting survival prospects and population stability. Critically, parental provisioning also explains why precocial bird species have smaller brains than altricial ones. Finally, these results suggest that the cognitive adaptations that provide the behavioral flexibility to improve reproductive success and survival are intrinsically linked to successful parental provisioning. Our findings also suggest that the traditionally assessed cognitive abilities may not predict relative brain size.

Modeling the effects of Aedes aegypti’s larval environment on adult body mass at emergence

Mosquitoes vector harmful pathogens that infect millions of people every year, and developing approaches to effectively control mosquitoes is a topic of great interest. However, the success of many control measures is highly dependent upon ecological, physiological, and life history traits of mosquito species. The behavior of mosquitoes and their potential to vector pathogens can also be impacted by these traits. One trait of interest is mosquito body mass, which depends upon many factors associated with the environment in which juvenile mosquitoes develop. Our experiments examined the impact of larval density on the body mass of Aedes aegypti mosquitoes, which are important vectors of dengue, Zika, yellow fever, and other pathogens. To investigate the interactions between the larval environment and mosquito body mass, we built a discrete time mathematical model that incorporates body mass, larval density, and food availability and fit the model to our experimental data. We considered three categories of model complexity informed by data, and selected the best model within each category using Akaike’s Information Criterion. We found that the larval environment is an important determinant of the body mass of mosquitoes upon emergence. Furthermore, we found that larval density has greater impact on body mass of adults at emergence than on development time, and that inclusion of density dependence in the survival of female aquatic stages in models is important. We discuss the implications of our results for the control of Aedes mosquitoes and on their potential to spread disease.

Do Early-Life Social, Behavioral, and Health Exposures Increase Later-Life Arthritis Incidence?

Objectives: This study investigates direct and indirect influences of childhood social, behavioral, and health exposures on later-life osteoarthritis and rheumatoid arthritis development. Methods: Drawing from cumulative inequality theory and six waves of the Health and Retirement Study (2004–2014), we estimate structural equation modeling-based discrete-time survival analysis of the association between six childhood exposure domains and both osteoarthritis and rheumatoid arthritis incidence for men ( n = 2720) and women ( n = 2974). Using the delta method to test for mediation, we examine indirect effects via selected health-related risks and resources. Results: Risky adolescent behavior is associated with rheumatoid arthritis incidence for women (h.O.R. = 1.883, 95% C.I. [1.016, 3.490]), whereas several types of childhood exposures are associated with later-life osteoarthritis development for both men and women. Experiencing two or more childhood socioeconomic disadvantages is indirectly associated with osteoarthritis (men: coef. = 0.024, 95% C.I. [0.003, 0.045]; women: coef. = 0.111, 95% C.I. [0.071, 0.150]) and rheumatoid arthritis (men: coef. = 0.037, 95% C.I. [0.000, 0.074]; women: coef. = 0.097, 95% C.I. [0.035, 0.159]) development through adult body mass index. Discussion: Findings highlight the importance of childhood contexts in understanding the development of later-life osteoarthritis and rheumatoid arthritis.

Pediatric data from the All of Us research program: demonstration of pediatric obesity over time

Objective To describe and demonstrate use of pediatric data collected by the All of Us Research Program. Materials and Methods All of Us participant physical measurements and electronic health record (EHR) data were analyzed including investigation of trends in childhood obesity and correlation with adult body mass index (BMI). Results We identified 19 729 participants with legacy pediatric EHR data including diagnoses, prescriptions, visits, procedures, and measurements gathered since 1980. We found an increase in pediatric obesity diagnosis over time that correlates with BMI measurements recorded in participants’ adult EHRs and those physical measurements taken at enrollment in the research program. Discussion We highlight the availability of retrospective pediatric EHR data for nearly 20 000 All of Us participants. These data are relevant to current issues such as the rise in pediatric obesity. Conclusion All of Us contains a rich resource of retrospective pediatric EHR data to accelerate pediatric research studies.

Pulses of anthropogenic food availability appear to benefit parents, but compromise nestling growth in urban red-winged starlings

The provision of anthropogenic food undoubtedly influences urban bird fitness. However, the nature of the impact is unclear, with both benefits and costs of urban diets documented. Moreover, the influence of short-term fluctuations in food availability, linked to urban weekday/weekend cycles of human presence, is largely unknown. We explored whether breeding red-winged starlings Onychognathus morio in Cape Town, South Africa, altered foraging and provisioning behaviour between days with high human presence (HHP) and days with low human presence (LHP)—i.e. weekdays versus weekends and vacation days. We investigated the relationship between starling diet, adult body mass and nestling development. Breeding adults consumed and provisioned the same quantity of food, but a significantly greater proportion of anthropogenic food on HHP compared to LHP days. Adults apparently benefited from the anthropogenic diet, experiencing significantly greater mass gain on HHP days. However, nestlings experienced a cost, with the number of HHP days during the nestling period associated negatively with nestling size. Adults may, therefore, benefit from the high calorie content of anthropogenic food, while nestlings may be negatively affected by nutrient limitation. The quantity of food available in urban environments may, therefore, benefit adult survival, while its quality imposes a cost to nestling growth.

1249Trends and disparities in adult body mass index across 47 prefectures in Japan, 1975–2018

Background Consistent and comparable health information across prefectures is necessary for monitoring progress in improving population health and reducing geographic health disparities in Japan. We aimed to examine long-term trends and variations in adult body mass index (BMI) by prefecture. Methods We obtained a total sample of 233,988 males and 261,086 females aged 20–79 years with anthropometric measurements from National Health and Nutrition Surveys conducted annually during 1975–2018. We applied a spatio-temporal Bayesian hierarchical model to estimate the annual time series of prefectural mean BMI by 20-year age group and sex. Results Prefectural mean BMI consistently increased in males regardless of age but decreased in younger females. It increased in older females until starting to decrease in the early 2000s. Mean BMI was noticeably higher in Okinawa, the southernmost prefecture, than in other prefectures from 1975 in males and from the 1990s in females. The interquartile range of mean BMI across prefectures was consistently higher in females than in males. It decreased over time to plateau during the 2000s in both sexes. Conclusions Mean BMI increased in males across prefectures and there is a need for stimulating a further reduction in geographic disparities particularly for females. Okinawa once ranked first in longevity but has shown relatively poor performance in recent years, which may be partly attributable to the distinctive trends in adult BMI. Key messages Bayesian hierarchical modelling is useful for reconstructing long-term spatio-temporal trends of mean BMI by integrating small-size survey samples.

289Birthweight and risks of adult-onset diabetes in women who are and are not overweight

Background Higher adult body mass index (BMI) increases diabetes risk, whereas, paradoxically, lower birthweight is associated with higher risks of adult-onset diabetes. Increased diabetes risks associated with low birthweight might be due to increased risks among those who become overweight or obese as adults but evidence on risks among those of normal BMI is limited. Methods In the Million Women Study, 413,516 women without prior diabetes, at mean age 60(SD5) years, reported their birthweight, and current height and weight. Birthweight and BMI at age 60 years were validated against recorded values at similar ages. Participants were followed for diabetes by electronic linkage to national hospital admissions records. Cox regression yielded multivariable-adjusted relative risks (RRs) for diabetes, overall and subdivided simultaneously by categories of birthweight and adult BMI. Results During 15(SD3) years follow-up, 24,528 women had hospital admissions with diabetes, first recorded at average age 70(SD6) years. Adult-onset diabetes risks increased strongly with increasing adult BMI (RR per 5 kg/m2 increase: 2.03, 95% CI 2.01-2.06). Compared to those with birthweight 3.0-3.4 kg, RRs of diabetes for birthweight <2.5 kg and ≥4.0 kg were 1.35(1.30-1.38) and 0.73(0.70-0.75), respectively. The association between low birthweight and increased diabetes risk was strongly evident among women who were of normal BMI, overweight and obese (p < 0.0001 for each). Conclusions At every level of adult adiposity, there were strong inverse associations between birthweight and adult-onset diabetes risk. Key messages While adult adiposity increases diabetes risk, there is a strong and independent increase in diabetes risk with decreasing birthweight.

Muscles, Nerves, and Skin

The muscles of giraffes are similar to those of other artiodactyls but differ in order to accommodate the stresses associated with an extraordinary shape. Extensor muscles of the neck are relatively small but flexor muscles of the neck that have to contract against the elasticity of the ligament nuchae are well-developed. The muscle bodies of neck muscles are located at the base of the neck and exert their effects via long tendons, which minimizes neck mass. Giraffes rarely lie down, or sleep, or run. Consequently limb muscles give support more than movement and are more tendinous that muscular. The power to run is generated by hip flexors and extensors, aided by contractions of the gastrocnemius muscles. The forelimb is the main support for body mass and acts as the fulcrum for movement. Chest and forelimb muscles keep the shoulder and elbow joints rigid, but allow drinking and the complications that arise from it. Brain mass forms 0.5% of adult body mass. Eyes are large and the retina has a unique distribution of photoreceptors that provides both clear images of close objects and allows focusing on ground level objects. Peripheral nerves contain more sensory than motor fibers. The skin of giraffes forms ~10% of body mass, and has more collagen than elastic fibers. Skin panniculus muscles are absent, an absence compensated by sebaceous gland secretion of volatile compounds that repel insects. The development of the colors of skin markings begins in the last trimester of pregnancy.