Correlated longitudinal changes across linguistic, achievement, and psychomotor domains in early childhood: Evidence for a global dimension of development

This is the peer reviewed version of the following article: Rhemtulla, M., & Tucker-Drob, E. M. (2011). Correlated longitudinal changes across linguistic, achievement, and psychomotor domains in early childhood: Evidence for a global dimension of development. Developmental Science, 14(5), 1245–1254. http://doi.org/10.1111/j.1467-7687.2011.01071.x, which has been published in final form at http://doi.org/10.1111/j.1467-7687.2011.01071.x. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.An important question within developmental psychology concerns the extent to which the maturational gains that children make across multiple diverse domains of functioning can be attributed to global (domain-general) developmental processes. The present study investigated this question by examining the extent to which individual differences in change across children’s development in five different domains are correlated. Multivariate growth-curve models were fit to longitudinal data on linguistic, mathematics, reading, gross motor, and fine motor skills in 8,950 children ranging in age from 44 to 86 months (3.7 years to 7.2 years). All five rates of change were positively intercorrelated. A common factor accounted for 42% of the individual differences in change. These results suggest that a global dimension underlies substantial proportions of cognitive and psychomotor development

Gene-by-Socioeconomic Status Interaction on School Readiness

In previous work with a nationally representative sample of over 1,400 monozygotic and dizygotic twins born in the US, Tucker-Drob et al. (Psychological Science, 22, 125–133, 2011) uncovered a gene × environment interaction on scores on the Bayley Short Form test of mental ability (MA) at 2 years of age—higher socioeconomic status (SES) was associated not only with higher MA, but also with larger genetic contributions to individual differences in MA. The current study examined gene × SES interactions in mathematics skill and reading skill at 4 years of age (preschool age) in the same sample of twins, and further examined whether interactions detected at 4 years could be attributed to the persistence of the interaction previously observed at 2 years. For early mathematics skill but not early reading skill, genetic influences were more pronounced at higher levels of SES. This interaction was not accounted for by the interaction observed at 2 years. These findings indicate that SES moderates the etiological influences on certain cognitive functions at multiple stages of child development

Small montane cloud forest fragments are important for conserving tree diversity in the Ecuadorian Andes

Montane tropical cloud forests, with their complex topography, biodiversity, high numbers of endemic species, and rapid rates of clearing, are a top global conservation priority. However, species distributions at local and landscape scales in cloud forests are still poorly understood, in part because few regions have been surveyed. Empirical work has focused on species distributions along elevation gradients, but spatial variation among forests at the same elevation is less commonly investigated. In this study, the first to compare tree communities across multiple Andean cloud forests at similar elevations, we surveyed trees in five ridge‐top forest reserves at the upper end of the ‘mid‐elevation diversity bulge’ (1900–2250 masl) in the Intag Valley, a heavily deforested region in the Ecuadorian Andes. We found that tree communities were distinct in reserves located as close as 10 to 35 km apart, and that spatially closer forests were not more similar to one another. Although larger (1500 to 6880 ha), more intact forests contained significantly more tree species (108–120 species/0.1 ha) than smaller (30 to 780 ha) ones (56–87 species/0.1 ha), each reserve had unique combinations of more common species, and contained high proportions of species not found in the others. Results thus suggest that protecting multiple cloud forest patches within this narrow elevational band is essential to conserve landscape‐level tree diversity, and that even small forest reserves contribute significantly to biodiversity conservation. These findings can be applied to create management plans to conserve and restore cloud forests in the Andes and tropical montane cloud forests elsewhere.RESUMENLos bosques nublados tropicales montanos, con su compleja topografía, biodiversidad, alto número de especies endémicas, y altas tasas de tala de bosque son una prioridad de conservación global. Sin embrago, la distribución de especies a escala local y de paisaje en bosques nublados es aun pobremente entendida, en parte porque pocas regiones han sido muestreadas. Estudios empíricos se han enfocado en la distribución de especies a lo largo de gradientes altitudinales, pero la variación espacial entre bosques ubicados a la misma elevación ha sido comúnmente menos investigada. En este estudio, el primero en comparar comunidades de árboles a lo largo de múltiples bosques nublados Andinos en elevaciones similares, muestreamos árboles en cinco reservas de bosque de cresta de montaña en el límite superior del pico de diversidad de elevaciones intermedias (‘mid‐elevation diversity bulge’) (1900–2250 m.s.n.m.) en el Valle de Intag, una región altamente deforestada en los Andes ecuatorianos. Encontramos que las comunidades de árboles fueron distintas en reservas tan cercanas como de 10 a 35 km de distancia entre sí, y que bosques espacialmente más cercanos no fueron más similares entre ellos. Aunque bosques extensos más intactos contuvieron significativamente más especies de árboles (108–120 especies/0.1 ha) que los de menor tamaño (56–87 especies/0.1 ha), cada reserva tuvo una combinación única de especies comunes, y una alta proporción de especies no encontradas en las otras reservas. Los resultados sugieren que proteger múltiples parches de bosque nublado dentro de este estrecho rango altitudinal es esencial para conservar la diversidad de árboles a escala de paisaje, y que aun pequeñas reservas de bosque contribuyen significativamente a la conservación de la biodiversidad. Estos resultados se pueden aplicar para la creación de planes de manejo para conservación y restauración del bosque nublado en los Andes y bosques tropicales montanos en otros sitios.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144672/1/btp12542_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144672/2/btp12542.pd

What is the <em>p</em>-factor of psychopathology? Some risks of general factor modeling

Recent research has suggested that a range of psychological disorders may stem from a single underlying common factor, which has been dubbed the p-factor. This finding may spur a line of research in psychopathology very similar to the history of factor modeling in intelligence and, more recently, personality research, in which similar general factors have been proposed. We point out some of the risks of modeling and interpreting general factors, derived from the fields of intelligence and personality research. We argue that: (a) factor-analytic resolution, i.e., convergence of the literature on a particular factor structure, should not be expected in the presence of multiple highly similar models; and (b) the true underlying model may not be a factor model at all, because alternative explanations can account for the correlational structure of psychopathology