Category Archives: 4.5 Billion Years of Earth’s History(4.5BYEH)

Micro-climate Control

A microclimate is a local atmospheric zone where the climate differs from the surrounding area. Microclimates exist, for example, in greenhouses, near bodies of water which may cool the local atmosphere, or in heavily urban areas where brick, concrete, and asphalt absorb the sun’s energy, heat up, and reradiate that heat to the ambient air: the resulting urban heat island is a kind of microclimate. Microclimate of an area can be affected by the altitude, exposure, presence of shelter, amount and flow direction of water,…

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Conifers

Conifers are cone-bearing seed plants with vascular tissue. All living conifers are woody: most are trees; some are shrubs. The earliest conifers appear in late Carboniferous  (Pennsylvanian) period (~ 300 mya). These plants do not depend much on water. Other adaptations are pollen (so fertilization  can occur without water) and the seed, which allows the embryo to be transported and developed elsewhere. Conifers were eventually overtaken by the flowering plants, which first appeared in the Cretaceous. Flowering plants became dominant in the Cainozoic era. References:1. https://www.hunker.com/12494374/types-of-coniferous-trees 2. https://www.hgtv.com/outdoors/flowers-and-plants/branching-out-a-guide-to-conifers

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Cycads and cycadeoids

Cycads and the extinct Cycadeoids (Bennettitales) are closely related gymnosperms. The basic difference between the two is that cones occur at the apex top of the stem in living cycads [Figure 1], but are embedded among the leaf bases in cycadeoids [Figure 2]. Cycadeoids are easily recognized by the diamond-shaped leaf bases of the trunk.  In many well-preserved specimens, you’ll see the cones of a Cycadeoid among the leaf bases. Figure 1. Cycadalean structure (from Tidwell, 1998)Figure 2. Cycadeoidalean structure (from Tidwell, 1998) Bennettiales from the Sedgwick…

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Ginkgo biloba – The Living Fossil

Ginkgo is a large tree with fan-shaped leaves. Although Ginkgo is a native plant to China, Japan, and Korea, it has been grown in Europe since around 1730 and in the United States since around 1784. The ginkgo tree is thought to be one of the oldest living trees, dating back to more than 200 million years. Ginkgo leaf is often taken by mouth for memory disorders including Alzheimer’s disease. It is also used for conditions that seem to be due to reduced blood flow…

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Tree Ferns

It is not certain the exact number of species of tree ferns there are, but it may be closer to 600-700 species. Many species have become extinct in the last century as forest habitats have come under pressure from human intervention. Location of species Lophosoria (tropical America, 1 species) Metaxya (tropical America, 1 species) Sphaeropteris (tropical America, India, southeastern Asia to New Zealand, the Marquesas, and Pitcairn Island, about 120 species) Alsophila (pantropic area, about 230 species) Nephelea (tropical America, about 30 species) Trichipteris (tropical…

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Plants of Jurassic Period

Jurassic Period, second of three periods of the Mesozoic Era. Extending from 201.3 million to 145 million years ago, it immediately followed the Triassic Period (251.9 million to 201.3 million years ago) and was succeeded by the Cretaceous Period (145 million to 66 million years ago). The Morrison Formation of the United States and the Solnhofen Limestone of Germany, both famous for their exceptionally well-preserved fossils, are geologic features that were formed during Jurassic times. The Jurassic Period was named early in the 19th century,…

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