Flower Power Through Hybridization - Pericallis sp.

Many flower species of the world are endangered or threatened by human activities and the ecological changes we are bringing about, and this is especially true for the flora of islands. Our June/Summer unknown is a descendant of flower species from the Canary Islands (and nearby islands). Originally brought to England's famous Royal Botanical Garden at Kew in 1776 by the Scottish botanist Francis Masson, these flowers were thought to be species of Senecio, a diverse genus of the Family Compositae (now also called Asteraceae - the sunflower family).

Over the decades, these flowers have been selectively bred, and in some cases, hybridized to form a variety of colorful garden varieties now often called "Florist's Cineraria". From examples such this plant and other plant breeds, as well as pigeons, sheep, cattle, dogs and other domesticated animals, Charles Darwin recognized that plant and animal breeders were capable of creating new variants of a species through selective breeding. This understanding formed an important part of his discovery and documentation of evolution through natural and sexual selection.

These Canary Island flowers have now been re-classified as members of genus Pericallis. There are 14 endemic (found only in one region) members of the genus Pericallis in the Canary and surrounding islands. Recent studies indicate they evolved from a single woody ancestor species of Cineraria that was somehow introduced long ago to the Canary Island group from Africa. This has been shown by comparing the molecular genome of Pericallis species with that of similar species from both Africa and South America. Until these experiments, botanists had hypothesized that Pericallis originated from a South American ancestor (genus Packera) that had rafted around the Atlantic in the Gulf Stream.

Again, the work of Darwin and other biologists comes to mind in revealing how speciation and diversification can occur rapidly from one (or a small number of) founder species, especially on small islands or groups of islands such as the Canary or Galapagos Islands.