RESUMO
The New World Vulture [Coragyps] occidentalis (L. Miller, 1909) is one of many species that were extinct by the end of the Pleistocene. To understand its evolutionary history we sequenced the genome of a 14,000 year old [Coragyps] occidentalis found associated with megaherbivores in the Peruvian Andes. occidentalis has been viewed as the ancestor, or possibly sister, to the extant Black Vulture Coragyps atratus, but genomic data shows occidentalis to be deeply nested within the South American clade of atratus. Coragyps atratus inhabits lowlands, but the fossil record indicates that occidentalis mostly occupied high elevations. Our results suggest that occidentalis evolved from a population of atratus in southwestern South America that colonized the High Andes 300 to 400 kya. The morphological and morphometric differences between occidentalis and atratus may thus be explained by ecological diversification following from the natural selection imposed by this new and extreme, high elevation environment. The sudden evolution of a population with significantly larger body size and different anatomical proportions than atratus thus constitutes an example of punctuated evolution.
Assuntos
Aves , Fósseis , Animais , Aves/anatomia & histologia , América do SulRESUMO
OBJECTIVE: To determine demographic, maternal, and child factors associated with socioemotional (SE) problems and chronic stress in 1-year-old children. STUDY DESIGN: This was a prospective, longitudinal, community-based study, which followed mother-infant dyads (n = 1070; representative of race, education, and income status of Memphis/Shelby County, Tennessee) from midgestation into early childhood. Child SE development was measured using the Brief Infant-Toddler Social and Emotional Assessment in all 1097 1-year-olds. Chronic stress was assessed by hair cortisol in a subsample of 1-year-olds (n = 297). Multivariate regression models were developed to predict SE problems and hair cortisol levels. RESULTS: More black mothers than white mothers reported SE problems in their 1-year-olds (32.9% vs 10.2%; P < .001). In multivariate regression, SE problems in blacks were predicted by lower maternal education, greater parenting stress and maternal psychological distress, and higher cyclothymic personality score. In whites, predictors of SE problems were Medicaid insurance, higher maternal depression score at 1 year, greater parenting stress and maternal psychological distress, higher dysthymic personality score, and male sex. SE problem scores were associated with higher hair cortisol levels (P = .01). Blacks had higher hair cortisol levels than whites (P < .001). In the entire subsample, increased hair cortisol levels were associated with higher parenting stress (P = .001), lower maternal depression score (P = .01), lower birth length (P < .001), and greater length at 1 year of age (P = .003). CONCLUSION: Differences in maternal education, insurance, mental health, and early stress may disrupt SE development in children. Complex relationships between hair cortisol level in 1-year-olds and maternal parenting stress and depression symptoms suggest dysregulation of the child's hypothalamic-pituitary-adrenal axis.