Origin of Species Variorum

Comparison with 1869

structures which are common to whole groups of species, and which in truth are simply due to inheritance; for an ancient progenitor may have acquired through natural selection some one modification in structure, and, after thousands of generations, some other and independent modification; and these two modifications, having been transmitted to a whole group of descendants with diverse habits, would naturally be thought to be correlated in some necessary manner. Some correlations are apparently due to the manner in which natural selection acts. ↑ For instance, Alph. De Candolle has remarked that winged seeds are never found in fruits which do not open: I should explain this rule by the impossibility of seeds gradually becoming winged through natural selection, unless the capsules first opened themselves; for in this case alone could the seeds, which were a little better adapted to be wafted by the wind, gain an advantage over those less well fitted for wide dispersal.

Compensation and Economy of Growth .

The elder Geoffroy and Goethe propounded, at about the same period, their law of compensation or balancement of growth; or, as Goethe expressed it, "in order to spend on one side, nature is forced to economise on the other side." I think this holds true to a certain extent with our domestic productions: if nourishment flows to one part or organ in excess, it rarely flows, at least in excess, to another part; thus it is difficult to get a cow to give much milk and to fatten readily. The same varieties of the cabbage do not yield abundant and nutritious foliage and a copious supply of oil-bearing seeds. When the seeds in our fruits become atrophied, the fruit itself

structures which are common to whole groups of species, and which in truth are simply due to inheritance; for an ancient progenitor may have acquired through natural selection some one modification in structure, and, after thousands of generations, some other and independent modification; and these two modifications, having been transmitted to a whole group of descendants with diverse habits, would naturally be thought to be correlated in some necessary manner. ↑ So, again, some correlations, occurring throughout whole orders, are apparently due to the manner alone in which natural selection can act. For instance, Alph. de Candolle has remarked that winged seeds are never found in fruits which do not open: I should explain the rule by the fact that seeds could not gradually become winged through natural selection, except in fruits which opened; so that the individual plants producing seeds which were a little better fitted to be wafted further, might get an advantage over those producing seed less fitted for dispersal; and this process could not possibly go on in fruit which did not open.

Compensation and Economy of Growth .