Oak symbolism in the light of genomics

Abstract

Throughout the Northern Hemisphere, human societies, political systems, and religions have appropriated oaks in symbolic representations. In this review, we explore the possible associations between recent genetic and genomic findings and the symbolic representations of oaks. We first consider the ways in which evolutionary history during the Holocene has tightened links between humans and oaks in Europe, and how this may have led to symbolic representations. We then show how recent findings concerning the structure and evolution of the oak genome have provided additional knowledge about symbolic representations, such as longevity, cohesiveness, and robustness.

Keywords: Quercus; interspecific gene flow; oak biodiversity; oak genomics; plant resistance; plant speciation; tree longevity; tree mutation rates.

Figure 1. An illustrative example of the endorsement of oak trees as a symbol of human values: the Gernika tree, a pedunculate oak standing in front of the parliament of the Biscay province of the Basque Country.

a) A third-generation offspring of the original Gernika tree in front of la Casa de Juntas (House of Assemblies), Basque Country, Spain. This tree became a symbol of liberty, as leaders of the Biscay province and, later, of the Basque people as a whole, swore an oath below the tree to safeguard the freedom of the Basque people. b) The Gernika tree depicted in a stained-glass window in the ceiling of la Casa de Juntas showing a Lord of Biscay swearing an oath to safeguard the freedom of the Basque people. c) Painting from la Casa de Juntas showing one of the first assemblies of representatives beneath the Gernika tree. General assemblies of people’s representatives from villages and provinces subsequently met near the tree to pass laws, and the tree became a symbol of justice and the unity of the Basque people. The French philosopher Jean Jacques Rousseau cited these assemblies as an early form of democracy in “Le contrat social” (1762). d) Biscay coat of arms from la Casa de Juntas, with its representation of the Gernika tree. e) Poster of the 650^th anniversary of the establishment of Gernika.

Figure 2. Oak tree artwork as symbol of robustness of ideas (Bloomfield, 2012).

An illustrative symbolic oak representation linking art and science was the choice for a longitudinal oak tree section as artwork for the ceiling of the Natural History Museum of London in 2009. The artwork was planned to celebrate the 200^th anniversary of Darwin. A panel of art experts, museum experts and scientist selected the oak project from 10 proposals made by different artists. The work TREE proposed by artist Tania Kovats was chosen by unanimous decision. Her proposal was to embed in the ceiling a longitudinal 3 to 5 mm thick section of a 200 year old entire oak tree, from the ground to the canopy). The tree was 21 metres high and came from a managed forest of Longleat Estate in Wiltshire. The art work was meant as a replicate of the iconic drawing of the “Tree of life” by Darwin, which echoes in this contribution the “Tree of life” revered by early human populations (Andersson, 2007). As described by R.M. Bloomfield (2012) “Rendered in stalwart English oak, the artwork is a metaphor of the endurance of Darwin’s ideas, as well as Darwin’s own bravery and commitment to them”. Photo credit: https://mikesmithstudio.com/projects/tree-natural-history-museum/