. Heredity and evolution in plants. Heredity; Plants. EXPERIMENTAL EVOLUTION 107. Fig. S3-—Photograph of beans rolling down an inclined plane and accumulating at the base in compartments, which are closed in front by glass. The exposure was long enough to cause the, moving beans to appear as caterpillar-like objects hopping along the board. If we assume that the irregularity of shape of the beans is such that each may make jumps either toward the right or toward the left in rolling down the board, the laws of chance lead us to expect that in very few cases will these jumps be all in the same d
. Heredity and evolution in plants. Heredity; Plants. EXPERIMENTAL EVOLUTION 107. Fig. S3-—Photograph of beans rolling down an inclined plane and accumulating at the base in compartments, which are closed in front by glass. The exposure was long enough to cause the, moving beans to appear as caterpillar-like objects hopping along the board. If we assume that the irregularity of shape of the beans is such that each may make jumps either toward the right or toward the left in rolling down the board, the laws of chance lead us to expect that in very few cases will these jumps be all in the same direction, as indicated by the few beans collected in the compartments at the extreme right and left. Rather the beans will tend to jump in both right and left directions, the most probable condition being that in which the beans make an equal number of jumps to the right and to the left, as shown by the large number accumulated in the central compartment. If the board be tilted to one side, the curve of beans would be altered by this one-sided influence. In like fashion, a series of factors— either of environment or of heredity—if acting equally in both favorable and unfavorable directions, will cause a collection of ears of corn to assume a similar variability curve, when classified according to their relative size. Such curves, called Qu6telet's curves, are used by biometricians in classi- fjang and studying variations in plants and animals. (Photo by A. F. Blakeslee. Legend slightly modified from Journal of Heredity, June, 1916.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gager, C. Stuart (Charles Stuart), 1872-1943. Philadelphia, P. Blakiston's Son & Co.
Size: 1722px × 1450px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectplants, bookyear1920
