plant evolution
A long 3000 million years ago the earth was not suitable for life as the atmosphere contained little to no oxygen and without this, deadly ultra violet rays from the sun bombarded the unprotected surface. This lead to life beginning in the ocean where it was safe from the sun's rays. It was here that life began with bacteria and small microscopic plants, called algae. Algae is the worlds oldest known fossil. Found in rocks of South Africa and Central Australia up to 3100 years ago. The Age of Algae lasted more than 2000 million years old, which is about half of planet earth's lifetime. During this long period of time, some of the algae developed the ability of being able to make food by using the energy from sunlight to converts carbon dioxide and water into sugar or starch. This process was called photosynthesis.The next stage in the development in plants was 'The Age of Primitive Vascular Plants. This new period (the second stage) in plant history occurred within the next 50 million years (400-500 million years ago). Some of these developed root systems stems and leaves. They also formed woody tissue, which created stiffer stems, which eventually developed into tree trunks. They became tree-like and up to
In the final step came the new immigrant plant life from Asia. As Australia came into closer contact with Asia about four million years ago, some of Asia's plants began colonising suitable parts of Australia. As they were not adapted to dry conditions, the only suitable conditions for them were wet coastal areas of the north and parts of the tropical rainforest of Queensland. These immigrants included many new species of palms, paperback trees, ferns, vines, and mangroves. Last but not least we have 'The Age of Flowering plants' beginning just over 100 years ago this was the fourth and last leap forward in the development of the world's plants. Unlike flowering plants cycads and conifers relied on winds to dispense pollen from male to female cones, the flowering plants attracted insects and birds to move pollen from males to females. The first flowering plants to evolve seemed to be the palms, however soon after many others followed. These gradually became more numerous then plants that had existed before. These developed into many different shapes and sizes from tiny little wild flowers, to huge oak and gum trees. Their seeds are enclosed in layers of fruit, capable of withstanding severe changes in climate. Flowering plant
Some common words found in the essay are:
Age Flowering, Firstly Ancient, Antarctica Australia, Bearing Plants', Plant Evolution, Asia Australia, Vascular Plants, Age Algae, flowering plants, Central Australia, 'the age, stage plant, plant history, gum trees, developed ability, plant life, australia separated, stage plant history,
Approximate Word count = 831
Approximate Pages = 3 (250 words per page double spaced)
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