A study of woodland star wildflowers in the western United States has found remarkable diversity in the scent compounds produced by their flowers. Every species of woodland star, and even different populations within a species, may produce a unique floral bouquet, sometimes composed of dozens of scent compounds, to attract specialized insect pollinators.
Twelve species and subspecies of woodland star (Lithophragma) occur in a wide range of habitats throughout western North America. They have coevolved with a group of specialized moths, called Greya moths, that pollinate and lay eggs only in woodland star flowers. Although the plants lose some of their developing seeds to the moth larvae, the benefits the plants receive from pollination usually outweigh the costs.
The floral scent study, published February 11 in Proceedings of the National Academy of Sciences (PNAS), adds a surprising new layer to the complex relationship between woodland stars and their pollinators. Senior author John Thompson, professor of ecology and evolutionary biology at UC Santa Cruz, has been studying the coevolution of these species for several decades. The new study builds on previous work showing that the interactions of woodland star with Greya moths have widely varying outcomes in different ecosystems depending on which pollinators are present. MORE
Header image: The moth Greya politella pollinates Lithophragma flowers while laying its eggs in the flowers, as seen in this photo of the moth on a flower cut open to show the inside of the flower. Credit: John Thompson.