The history of classical Jewish thought is one of the conservation of ideas.
Not conservation as in ancient shards in a museum, pickles in a pickle jar or polar bears in a zoo. Rather, a creative, dynamic sort of conservation, much like the conservation of a lush and delicate ecosystem, carefully adjusting to adapt to changes of climate, to the rise and fall of waterways from beyond the forest, to the shifting winds and migrations of predators—organically, in harmony with the complex balance of the forest.
So too the Jewish People stood fast through every shift, retreat and lunge of history, unfolding yet more pages of their Torah through each one, clinging to the Tree of Life entrusted in their hands, much as the soil clings to an oak seed planted in its bosom, nurturing it to grow from the rains, to harden from the cold, to become strong from the winds, to spread its boughs and capture the rays of the sun, until it becomes a broad and mighty oak providing a home for teaming life, protection and beauty for all who sit in its shade.
In the end, the tree is as much a reflection of the climate it weathered as of the seed from which it grew; yet, perhaps most of all, it tells of the soil that refused to let it go.