What is the evolutionary history of Sequoia?
The early history of conifers, including the ancestors of modern Sequoia, parallels the evolution of dinosaurs. Their origins and major diversification was during the Mesozoic Era (Triassic, Jurassic and Cretaceous Periods) about 250-65 million years ago. Fossils of extinct genera indicate that a recognizable ancestral form of Sequoia had been established by at least100 million years ago. Species of the genus Sequoia reached their widest global distribution around 50 million years ago (when the middle and higher latitudes of the Northern Hemisphere were warmer than today), with fossils of that age found in North America, Europe, Asia nd even as far north as the Arctic Circle! A cooling and drying trend in global climate led to the loss of Sequoia forests except on the U.S. Pacific coast, where the uplifting of the coastal mountain ranges (about 5 million years ago) created a moist, temperate climate for modern Sequoia sempervirens.
