Plant collectors have become a force of evolution. The way in which they've harvested a Himalayan wildflower has inadvertently driven the species toward a shorter form, according to a new report.
Traditional healers in Asia have long prized the snow lotus (Saussurea laniceps), which grows only in the eastern Himalayas. The plants bloom just once, at the end of a life spanning at least 7 years. Particularly large blooming plants attract collectors, who consider them to have the greatest medicinal value.
Preferential collection of large specimens is selecting for shorter plants, says Wayne Law of Washington University in St. Louis. In heavily visited flower patches, harvesting has increased with the expans