In a study to be published in the journal Nature Plants, co-author Chang-Hsien Yang, a professor at the Graduate Institute of Biotechnology at the National Chung Hsing University found two protein complexes that control how orchids develop. One is responsible for the lips on the exotic plants and the other for the petals. Whichever complex is dominant in a specific plant will result in that plant either having various sizes of petals or very prominent lips.
Since the lip of the plant is the main pollinator, the proteins in the lip complex are very important for reproduction. Much like humans, the orchid that can use it's physical appearance to attract pollination and attention from others is the variety that will survive and thrive.