From: StellrJ at aol.com on 2002.02.03 at 08:41:29(8152)|
In a message dated Sat, 2 Feb 2002 11:25:09 AM Eastern Standard Time, Neil Carroll writes:
> Actually a simple experiment which can naturally choose over a short period
> of time is given in many basic texts on the subject....that is .......
> the dandylions in your lawn eventually only flower on short peduncles
> because the mower keeps cutting off the ones with long peduncles.
On the same note, I have seen a frequently-moved lawn on which wild carrot (Daucus carota) was flowering essentially at ground level. If you have seen the height of a "typical" wild carrot, this is indeed astonishing. If this is a true Darwinian evolution, one has to ask, how did the latent genes for shortness survive long enough to manifest, if the plants were constantly being mowed down before reaching flowering height? Or, perhaps it is not a true evolutionary event; perhaps the plants are showing abnormal behavior triggered by stress. Had I time and space enough, I could collect seeds from these dwarfed plants, plant them in a situation without mowing, and see whether the resulting seedlings (1) remain dwarfed, indicating a true Darwinian change; or (2) revert to the typical tall form (perhaps with some cytoplasmic stunting), indicating stress behavor on the part of the parents.