複選題26.(AB) There are about millions of cones in a human eye, with the highest concentration occurring towards the macula. (AC) However, their distribution is uneven, yielding nuanced consequences for visual perception. (AD) This dual arrangement reflects the evolutionary necessity of navigating two visual milieus—diurnal and nocturnal. (AE) This adaptive mechanism allows the pigment in each photoreceptor converts light into neural signals for the brain. (BC) But under scotopic conditions, rods will dominate, producing monochromatic vision. (BD) Consequently, object brightness can shift dramatically between photopic and scotopic conditions. (BE) Unfortunately, humans are often unable to view groups of cones at one time due to the constant motion of the eyeball.