In the rudimentary levels of biology, when one first learns the genetic process, Gregor Mendel is the first to be mentioned. Mendelian Inheritance describes the process by which genes and traits are passed from parent to offspring. Parents can have either dominant or recessive alleles.
This principle layers the framework for future geneticists, though Mendel did not explain all patterns of inheritance.
Flowers almost always hold an axis of symmetry, and are able to be divided into two or more mirror images. Two common types of symmetry are radial and bilateral symmetry. Symmetry should typically be passed onto future generations in a similar way to Mendel's model, although a flower type has proven differently in recent studies. 
C Carl Linnaeus (1707-1778) a prominent botanist and zoologist of his time, well known for his development of binomial nomenclature, first discovered a peculiar plant now named Linaria vulgaris. Linnaeus described the plant as having a radially symmetric mutant (Gustafsson, 1979). The Linaria vulgaris is naturally occurring in both types of symmetry, thus not created in a laboratory. In 1999 the cause of this peculiar genetic notion was uncovered by researchers. (Cubas et al, 1999)
Scientists found that the radially symmetric phenotype was the result of methylation at a gene site "Lcyc." In the radially symmetric mutant phenotype the researchers describe, "The Lcyc gene is extensively methylated and transcriptionally silent in the mutant. This modification is heritable and cosegregates with the mutant phenotype." (Cubas et al, 1999). The radially symmetric mutant phenotype often even reverts back to bilateral symmetry during somatic development.
[Linaria vulgaris occurring with bilateral symmetry (left) and radial symmetry (right).]
This epigenetic ability to exist with two distinct different phenotypes of plant symmetry is revolutionary. It is a heritable epigenetic modification that affects plants in a drastic way. The scientists conclude, "This indicates that epigenetic mutations may play a more significant role in evolution than has hitherto been suspected" (Cubas et al, 1999). Indeed, this drastic modification in phenotype proves epigenetics and evolution are intertwined.
Research has shown that the shape of a flower makes a large impact on the types of pollinators. For example, "...each category of pollinator (beetles, small, and medium-large bees) is associated with a syndrome of dependent floral characteristics (size, shape, and reward)," as described by Dafni et. al. when studying the implications of flower shape on pollination (Dafni et al, 1997). That being said, the ability for the Linaria vulgaris to change its symmetry epigenetically means the plant is able to rapidly evolve between generations and at different times in its life. This could give the flower the ability to adapt to the type of pollinators present at a given time.
Evolution and epigenetics is clearly demonstrated through the methylation of the Lcyc gene in the Linaria vulgaris and demonstrates a type of change in the phenotype that can prove to be advantageous to the plant.
References:
Cubas, P., Vincent, C., & Coen, E. (1999). An epigenetic mutation responsible for natural variation in floral symmetry. Nature, 401(6749), 157-161. http://www.nature.com/nature/journal/v401/n6749/full/401157a0.html
Dafni, A., & Kevan, P. G. (1997). FLOWER SIZE AND SHAPE: IMPLICATIONS IN POLLINATION. Israel Journal of Plant Sciences, 45(2-3), 201-211. doi: 10.1080/07929978.1997.10676684
Gustafsson, Å. (1979). Linnaeus' Peloria: The history of a monster. Theoretical and Applied Genetics, 54(6), 241-248. doi: 10.1007/BF00281206
Pictures all accessed 21/04/2015 and referenced from top to bottom of blog entry:
http://www.zo.utexas.edu/faculty/sjasper/images/f11.8.jpg
http://www.the-scientist.com/?articles.view/articleNo/19582/title/Notebook/
http://blog.tonge-moor.bolton.sch.uk/year6/wp-content/uploads/sites/8/2015/01/Linnaeus-290x3201.jpg
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9iT-VzfBX9GdZSmOoFPUGvBVQ68BBXKq_FdQowW9PmLUTrR_DdMxevrTcl7pOVtltQMcJ69dP_ugafLPauxYM3MG6HsSyGlqXXU-EZJRVQ8dWfezoLdz16SthVA2VYFdC0zzn40jjwHB8/s1600/flower+radial+bilateral.gif
You suggest that a change in symmetry could be highly beneficial for this flower, allowing it to exploit potentially different pollinators. However, if the structure of the flower changes, perhaps this might make it more difficult for pollinators to access or even recognize. Has there been research conducted looking at the fitness advantage / disadvantage of being bilaterally vs. radially symmetrical in this species, over different time periods and in different places? Interesting post.
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