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Evolution of the Big Bang! Screams the cover of Time magazine on December 4, 1995. "According to the results of the survey, started a new life as we know it will change frenzy attention being on our planet." Very hide from the animal's feeding Cambria beginning of period, about 545 million years ago in early Cambrian ... is certainly a new life, the invention of time. This rapid evolution is a form for a while, the new strategy is the family as the foundation of modern animals. Cambrian fossils were called in the past 100 years, they mark the end of the dark era, in the absence of fossils, geological and biological inspiration started. They Stephen J Gould "and a better life," he said.           The Blossoming of Life     Billions of years had passed, nearly nine-tenths of Earth history, when life finally made its vital leap into complexity. Now at last it could move on from dull primordial slime, and begin inventing the fabulous life-forms that we see today.   Of all the innovations conjured up by evolution, this was the most dramatic. It was the world's first industrial revolution. Before then, each individual cell had to be master of all trades: eat; digest; excrete; reproduce; perform all the essentials of life within one small squashy sac. Afterward, mighty corporations of cells sprang up to share the load. Specialization became the rule. Thanks to structural cells, bodies could grow large and adopt inventive new architectures. Muscle cells could move these bodies to new grazing grounds. Sensory cells could warn of danger, appendage cells could rake in supplies. Cells evolved to regulate temperature, transport information, innovate and consolidate.   And this specialization opened up a world of possibilities. Suddenly, in the Earth's late middle age, life began frantically procreating, evolving and developing new forms. First came trilobites and ammonites, then dinosaurs and octopuses, dromedaries, whales and wallabies, as the new complex creatures competed to find ever more imaginative ways of exploiting the world's resources. Life as big business was wildly successful.   Then why did it take so long? Though the history of life is ambiguous, traced through an imperfect record of fossils and rocks, most researchers believe that complexity was invented somewhere between 550 and 590 million years ago. That's after more than 3 billion years of simple, single-celled slime.   Biologists have been trying for decades to understand why complex life appeared on Earth at that particular moment...   To find the cause of a historical event, you first need to know when to look. And until recently, most biologists have assumed that complexity arose with an event called the Cambrian explosion. This episode has grabbed all the early-life attention for decades.   Evolution's Big Bang! screamed the front cover of Time magazine on December 4, 1995. "New discoveries show that life as we know it began in an amazing biological frenzy that changed our planet overnight." The animals that reared up on its cover were from the beginning of the Cambrian period, around 545 million years ago... The beginning of the Cambrian was certainly a burgeoning, inventive time for life. During this rapid burst of new evolutionary shapes and strategies, the foundations were set for every modern family of animals. The Cambrian fossils have been known for centuries; they mark the end of the Dark Ages without fossils and the beginning of geological and biological enlightenment. They are Stephen Jay Gould's "Wonderful Life." But all this fame has come to them mainly because they were easy to preserve. They show up everywhere. At the beginning of the Cambrian, life invented skeletons: scales, shells, spines, all the sorts of bodily supports that stick around long enough after death to turn into clear, unambiguous fossils.   So the Cambrian fossils weren't the first complex animals, any more than language began with the printing press, or with papyrus. Complex life could easily have been around for millions of years before then, and just not left such a clear record in the rocks.   The invention of multicellularity was certainly a prerequisite for the Cambrian explosion. Some biologists even say that it made the Cambrian explosion inevitable. Of course, life began experimenting with its new toy, exploring the many new possibilities it now had for shapes and functions, tissues and organs. With complexity already in place, the Cambrian explosion was just regular evolution in action.   So forget the brash fossils of the Cambrian. To find the real moment that life learned to use many cells instead of one, biologists need to seek out creatures that are much more mysterious...         — Gabrielle Walker, Snowball Earth: The Story of a Maverick Scientist and His Theory of the Global Catastrophe That Spawned Life As We Know It, Chapter 9 - Creation                         Indexes/19