The Ginko Biloba Tree

Ginkgo Leaf Fossil, Burke Museum, University of Washington, Seattle, Washington

The above photo of the Ginkgo Leaf Fossil was taken at the Burke Museum, University of Washington, Seattle, Washington and  represents a fossil of a Ginkgo taken in Smithers, British Columbia, Canada.  Driftwood Canyon Provincial Park, in Smithers, is one of the world's most significant fossil beds.   

The Ginkgo Biloba tree appears naturally, in the wild, only in China.  It is grown in many place worldwide, as a cultivated tree, and adapts well in well watered and well drained habitats. Ginkgo Biloba is a living fossil , dating back 270 millions to the Permian Period  .  Ginkgo has managed to evolve along a very long evolutionary time period without much speciation.

It is an interesting example of a plant that has had extreme longevity, slow growth, late reproductive maturity and has survived through many diverse and disturbed environments, including the Ice Age .  It has  managed, despite  a narrow base of speciation to support it.  It has two sexes, male and female, and has its ability to exhibit clonal reproduction, a process which produces a population of identical units which reproduce from the same ancestral line. This has helped it survive evolutionary challenges.  The Ginkgo is also highly resistant to air pollution and grows in areas where air pollution has damaged other species.

A HHMI BioInteractive presentation discusses the issue of clonal reproduction in a video. "Are Males Really Necessary?"  using fruits and vegetables as props.   The video is thought provoking and uses creative use tools to discuss an educational subject.  The 23rd or "sex chromosome"  is a specialized area of interest not explicitly discussed.  Protocols for tossing out wilted lettuce or black bananas present an analytic challenge.

The black banana we consider tossing out might be more useful than the newest banana, especially if we are considering  baking banana bread to bring to the next potluck.  It takes awhile to produce the necessary senescence in a banana to get the right flavor and texture for banana bread.  Thus,  Interoperability, whether it be in bread making, computer engineering or other systems, is an important evolutionary issue, involving mutations along with a stochastic process.

One has to wonder at the combination of processes that has sustained the Ginkgo for million years as well as the diverse environments that the Ginkgo tree  has experienced.   Ginkgo is an herb.  Its leaves and sometimes its seeds are used to make extracts for medicinal purposes, including memory disorders such as Alzheimers and dementia.  Even as we consider the marvel that is the Ginkgo Biloba, we find fascination and beauty in its foliage, and comfort in the shade that it produces.  It is a tree and much more.