Co-joined Rudbeckia Flower - Fasciation

I found this unusual beauty in my flower garden mixed in with the rest of the typical rudbeckia blooms.

This abnormal growth, known as fasciation, occurs in the plant tip or apical meristem. The apical meristem is found at the tips of the plant both on the roots and the stem. It is an area of actively dividing cells.

Fasciation causes elongation of the affected area of the meristem resulting in flattened ribbon like grow. It is seen here as flattened stem and crested bloom. The flower appears to be co-joined and the stem is flat and wide rather than the typical round stem of the other rudbeckia surrounding this plant. Notice that a flower lower on the stem is "unaffected".

According to the Master Gardener program at the University of Wisconsin-Extension, "although this condition is not common, it has been recorded in hundreds of different plant species, including ferns, woody plants, herbaceous annuals and perennials, and fruits and vegetables. The cause of fasciation is varied, but not well understood. In some cases this irregular growth is apparently triggered by infection (by bacteria, viruses or phytoplasmas), feeding by insects or other animals, chemicals or mechanical damage." There is some evidence of cellular mutation, hormonal imbalance or even extreme weather being possible causes, however, fasciation can sometimes just happen with no apparent cause".

No matter what the reason, the result can be fascinating and/or bizarre. I find it a delight to have this atypical flower gracing my garden. None of the other rudbeckia flowers in the garden exhibit this mutation making this one even more special.