A comment from a reader has prompted this post on a diminutive, but familiar local wildflower. Early Nancy turns out to be a pretty interesting plant. The male and female flowers are almost always borne on separate plants, with the photographs below showing the clear sexual differences between the flowers.
The scientific name for Early Nancy is Wurmbea dioica. Apparently “Wurmbea” comes from the name of a Dutchman from Java of the 18th century, F. van Wurmb, who was a naturalist, amateur botanist and merchant; “dioica” comes from the Greek and means “two houses”, referring to the plant’s habit of having male and female reproductive organs on separate plants (Bedingfield, 2003)
Research on the species in Western Australia revealed some fascinating insights. A study published in the journal Ecology (Case and Barrett, 2001), found that within the same area, monomorphic (cosexual) and dimorphic (male and female) populations of Early Nancy were present.
The authors noted … “Unisexuals flowered in late June and early July, and were widespread at low density throughout the drier areas of the study site, while smaller high-density patches of cosexuals flowered in late July and early August in wetter microsites, hence there was minimal opportunity for reproductive interactions between plants of the two sexual systems”. These strategies were explained in terms of an evolutionary response to maintain genetic and ecological differentiation between the sexual systems by restricting opportunities for hybridisation.
You’ll need to read the paper to get the full story … I must admit it nearly did my head in but I have even greater admiration for Early Nancy after learning more about it.
1. Early Nancy – an early starter in spring, by Michael Bedingfield (First printed in the Friends of the Grasslands Newsletter 2003)
2. A.L. Case and S.C.H. Barrett, Ecological differentiation of combined and separate sexes of Wurmbea dioica (Colchicaceae) in sympatry, Ecology, 82(9), 2001, pp. 2601–2616