| What We've Learned So Far |
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The Early Earth
Origins of Life
Mimi
The Experiment
First Organisms
Dawn Of Ocean Life
The Missing Link
Rise of Mammals
Extinction
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| Life's Big Questions |
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When?, Where?, What? The oldest known fossils, called stromatolites, are about 3.5 billion years old. Although debated, these colonial structures appear to ... more.
What Came Before DNA? Life remained almost exclusively unicellular for the first five sixths of its history - from the first recorded fossils at 3.5 billion ... more.
What were the first Organisms like? They resemble upside-down ice cream cones or egg cartons, but a new analysis suggests that the odd sedimentary ... more.
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| The Evolution of Life
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The history of life tends to move in quick and quirky episodes, rather than by gradual improvement. To understand the events and generalities of life's pathway, we must go beyond principles of evolutionary theory to a paleontological examination of the contingent pattern of life's history on our planet - the single actualized version among ... more.
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| The Missing Link
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Found in the Canadian Arctic, the new fossil boasts leglike fins, scientists say. The creature is being hailed as a crucial missing link between fish and land animals—including the prehistoric ancestors of humans. The new species, Tiktaalik roseae, had a flattened, crocodile-like head and strong, bony fins. The large fish probably flexed ... more.
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The prevailing view of early Earth is that it was utter hell, a fiery environment unsuitable for life. Scientist even named it the Hadean eon, for the ancient Greek word for the down under. But the planet may have been suitable for life ... more.
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All living organisms are made up of cells—membrane-enclosed organic sacks that contain proteins and strands of genetic material. Without the biological machinery inside, cellular membranes couldn't grow, multiply, or even ... more.
The discovery of new pre-Cambrian and Cambrian fossils help, as these transitional forms support the hypothesis that diversification was well underway before the Cambrian began ... more.
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In its 4.6 billion year history, Earth has undergone massive geologic and climatic changes and provided habitat to an ever-changing cast of life forms. In recent years, the origin and early evolution of life has seen an unprecedented development. The Earth provides the requisite conditions of liquid water, an environment where complex organic molecules can assemble.
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The Origin of the Moon is still uncertain, although much evidence exists for the giant impact hypothesis. Earth may not have been the only planet forming 150 million kilometers from the Sun. It is hypothesized... more.
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Just before the Cambrian, in the Late Proterozoic, large, multi-cellular life that had soft bodies (jellyfish, etc.) are found in the fossil record. The base of the Cambrian is defined as the occurrence of the first-hard shelled fossils. This does not mean that complex life did not... more.
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The Use of Sunlight by cells was a double achievement of great importance for life on Earth. Not only did the Sun provide an unlimited source of energy and assure a dependable supply of food, but it also drastically changed Earth’s atmosphere by... more.
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Mass Extinctions are ecological disasters. Yet they also create evolutionary opportunities by removing once-dominant groups. Some biologists conclude that Humans owe our present dominance to a mass extinction - the K/T event that saw the end of the dinosaurs and... more.
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The Mammals maintained a low-profile existence for some 150 million years. New fossil discoveries reveal more of this early history every year. In 2001, researchers reported that a fossil found in China in 1985 is the remains of a tiny, furry animal that was a relative of the... more.
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