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epigenetic landscape

a visual metaphor that depicts development as a hill with valleys of various depths and steepness, to convey the idea that some aspects of development are directed along certain general pathways and likely to occur under most circumstances but that the exact sequence of paths varies across individuals and can be altered by sudden environmental or genetic change. [proposed by British biologist Conrad Hall Waddington (1905–1975)]

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Psychology term of the day

February 26th 2024



n. red–green color blindness in which the deficiency is due to absence of the cone photopigment sensitive to green light, resulting in loss of green sensitivity and confusion between red and green (see dichromatism). The condition may be unilateral (i.e., color vision may be normal in one eye). See also protanopia.