futurism.com
Un estudio de J.M. Stibel, un científico cerebral del Museo de Historia Natural de Los Ángeles, ha confirmado que los cerebros humanos han disminuido significativamente en tamaño en los últimos 50.000 años.
El estudio encontró que el tamaño del cerebro ha disminuido en más de un cinco por ciento en el homosapiens moderno y la encefalización, principalmente debido a la obesidad.
Sin embargo, las medidas de inteligencia general y el logro educativo han aumentado en el último siglo.
El estudio de Stibel utiliza el coeficiente intelectual como una medida de inteligencia, que tiene una historia de privación de derechos y ha sido criticado por colapsar diferentes tipos de inteligencia.
Los cerebros humanos se están reduciendo
Human Brains Are Shrinking, Scientist Warns
J.M Stibel, a brain scientist, has discovered evidence that the size of human brains have greatly decreased in the past 50,000 years.
futurism.com
Decreases in Brain Size and Encephalization in Anatomically Modern Humans
Abstract. Growth in human brain size and encephalization is well documented throughout much of prehistory and believed to be responsible for increasing cognitive faculties. Over the past 50,000 years, however, both body size and brain mass have decreased but little is known about the scaling relationship between the two. Here, changes to the human brain are examined using matched body remains to determine encephalization levels across an evolutionary timespan. The results find decreases to encephalization levels in modern humans as compared to earlier Holocene H. sapiens and Late Pleistocene anatomically modern Homo. When controlled for lean body mass, encephalization changes are isometric, suggesting that much of the declines in encephalization are driven by recent increases in obesity. A meta-review of genome-wide association studies finds some evidence for selective pressures acting on human cognitive ability, which may be an evolutionary consequence of the more than 5% loss in brain mass over the past 50,000 years.
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