Pangaea’s Many Moods: The Eras

Somehow, I never stopped to consider that, to date, the Precambrian Era consumed 88% of geologic time. It began with Earth’s origin, 4.5 billion years ago (4,500,000,000); that’s a huge number. The first organisms were single-cell terrestrial algae. To quote Oilgae.com, “Terrestrial algae are inconspicuous and far more common in moist, tropical regions than dry ones, because algae lack vascular tissues and other adaptations to live on land.” Single cell algae were followed by multi-cell green algae. These are the plants that first developed photosynthesis. This glut of oxygen caused iron molecules, suspended in the ocean, to fall to the bottom, and form a layer of sediment. And as distant as the Precambrian was, colonies of stromatolites made their first appearance. Amazingly, they can still be found on the coast of Australia. The Cambrian Era, about 540 million years ago, brought us simple, branching algae, and the emergence of Pangaea.

The Ordovician Era, 490 million years ago, brought the extensive appearance of spores in non-vascular, terrestrial plants: liverworts, mosses, and hornworts (non-vascular plants with a horn-like structure that produces spores). A surprising number of mosses and liverworts were found to have ritual applications as either tools or medicine.

The first vascular plants made their appearance in the Silurian Era, 443 million years ago. The Devonian Era plants, about 417 million years ago, started out with no leaves and no roots. But as time progressed to the late Devonian Era, roots made their first appearance along with ferns and forests filled with trees that had real wood. Greenhouses gases dropped with the greening up and the Earth became cool enough to trigger the Late Devonian Extinction Event.

The Carboniferous Era began about 354 million years ago. We see the first horsetails, scrambling plants, club mosses, more ferns, and seed-producing plants such as conifers, cycads, and ginkgoes. Fronds of some of the carboniferous ferns are virtually identical to living species today. The Permian Era of 290 million years ago brought significant advances in conifers and ginkgoes.

The Mesozoic Era is divided into several parts. The Triassic of 248 million years ago brought us modern ginkgoes, conifers, and spore producing ferns. At the same time Pangaea began to languish. The Jurassic Era of 206 million years ago added more conifers, cycads, ginkgoes, and tree ferns to the great garden of Earth. The Cretaceous Era brought bees (!!!), grasses, the first flowering plants, figs, planes, magnolias, and more conifers. About 175 million years ago our beloved Pangaea began to break apart.

My short journey ends with the Cenozoic Era. It began 65 million years ago and reaches into present day. The Cenozoic went from dense forests that reached both the poles to vast savannahs, due to the planet cooling again. During this time we would find co-dependent flowering plants and insects, and more grasses. Extinctions of ancient species of animals led the way to flourishing and highly diverse mammals. The ever-changing gardens led to both evolution and extinction. My reason to conclude my essay here is simple: the continents had finally reached their present day locations, and the Gardens of Pangaea quietly subsided. Each continent began to evolve its own unique and glorious garden.

Should you be interested in our place in geologic history, there are excellent primer articles in the Sacred First Foods blog.




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