Resumen de Eyeing Redness.
The article reports that neurobiologists from the California Institute of Technology theorize that color vision may have originated in humans and primates related to them in order to distinguish blushing or paleness in faces. They explain that two color photoreceptors in humans and other primates from the Old World are most sensitive to roughly 550 nanometer wavelength light. This sensitivity is used to detect subtle changes in skin tone caused by concentration of oxygenated hemoglobin in the blood.
