BioConcepts

pangenesisPangenesis (ger.)

• A theory postulated by Darwin to explain the phenomena of heredity, according to which every constituent unit of an organism reproduced itself by contributing particles (gemmules) to the organism's reproductive cells. (OED 2012)
  category heredity

  1868

  I venture to advance the hypothesis of Pangenesis, which implies that the whole organization, in the sense of every separate atom or unit, reproduces itself. Hence ovules and pollen-grains—the fertilized seed or egg, as well as buds—include or consist of a multitude of germs thrown off from each separate atom of the organism. […] it is very difficult to believe that the early cells or units possess the inherent power, independently of any external agent, of producing new structures wholly different in form, position, and function. But these cases become plain on the hypothesis of pangenesis. The organic units, during each stage of development, throw off gemmules, which, multiplying, are transmitted to the offspring. In the offspring, as soon as any particular cell or unit in the proper order of development becomes partially developed, it unites with (or to speak metaphorically is fertilised by) the gemmule of the next succeeding cell, and so onwards. Now, supposing that at any stage of development, certain cells or aggregates of cells had been slightly modified by the action of some disturbing cause, the cast-off gemmules or atoms of the cell-contents could hardly fail to be similarly affected, and consequently would reproduce the same modification. This process might be repeated until the structure of the part at this particular stage of development became greatly changed, but this would not necessarily affect other parts whether previously or subsequently developed. In this manner we can understand the remarkable independence of structure in the successive metamorphoses, and especially in the successive metageneses of many animals.

  Darwin, C. (1868). The Variation of Animals and Plants under Domestication, 2 vols.: II, 359; 389.

  1982

  pangenesis Theory of heredity, that somatic cells contain particles (gemmules) that can be influenced by the environment and the activity of the organs containing them; these particles can move to the sex cells to influence the course of heredity; gemmule theory.

  Lincoln, R.J., Boxshall, G.A. & Clark, P.F. (1982). A Dictionary of Ecology, Evolution and Systematics: 181.