. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings; Sexual selection in animals; Sexual dimorphism (Animals); Sex differences. FISHES. 379 |>ared with the tusks of many male mammals, and they uvdicate an offensive rather than a protective purpose. The salmon is not the only fish in which the teeth differ ii\ the two sexes; as this is the case with many rays. In. Fig. 3a Head of female salmon. the thombaok {Raia Clavata) the adult male has sharp/ oointed teeth, directed backward, w^hile those of the female ire broad and flat, and form
. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings; Sexual selection in animals; Sexual dimorphism (Animals); Sex differences. FISHES. 379 |>ared with the tusks of many male mammals, and they uvdicate an offensive rather than a protective purpose. The salmon is not the only fish in which the teeth differ ii\ the two sexes; as this is the case with many rays. In. Fig. 3a Head of female salmon. the thombaok {Raia Clavata) the adult male has sharp/ oointed teeth, directed backward, w^hile those of the female ire broad and flat, and form a pavement; so that these ^.eeth differ in the two sexes of the same species more than Js usual in distinct genera of the same family. The teeth J)f the male become sharp only when he is adult; while JrQung they are broad and flat like those of the female. As. 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 Darwin, Charles, 1809-1882. New York : A. L. Burt
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Keywords: ., bookcentury1800, bookdecade1870, booksubjecthumanbeings, bookyear
