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The world's wildlife is vanishing at an alarming rate. Scientists at the Nature Conservancy and the World Wildlife Federation estimate that one in four mammals, and a full third of Earth's amphibians are in danger of becoming extinct. Today species are becoming extinct at a rate that is anywhere from 100 to 1,000 times faster than normal. People have been in fierce competition with wild animals for land, food, and natural resources for years. When over-hunting and -fishing of species and a rise in the level of pollution is added to this mix, humans come to represent the single gravest threat to wildlife survival. Any species that disappears leaves a hole in the web of life. Mass extinction would leave so many holes that the web might totally fall apart. Humans must realize the important role wildlife plays in the survival of the planet and reverse the damage--before it's too late.
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Emeralds are the most expensive gems in the world, but it takes a lot of time and effort for them to get that way. Readers will discover many interesting facts about this beautiful May birthstone that takes millions of years to form. Vibrant photographs capture emeralds at all stages, from the mines to beautiful pieces of jewelry.
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There are many different types of diamonds in the world. They come in a range of colors and can be cut into all kinds of shapes. This book shows readers that the way these different kinds of diamonds are created really isn't that different at all. Interesting facts and detailed photographs explain where these gems come from, how they're made into jewelry, and what makes them so valuable.
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Some of the most important contributors to the food chain are those creatures that help break things down: decomposers. If not for these birds, bugs, and worms organic matter couldn't be recycled back into nature. Readers will discover the different kinds of decomposers, how they do their job, and why it is so important. This fascinating book includes graphic organizers and annotated illustrations to better explain the food chain.
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Amazing mountain animals fill the pages of this exciting series. Redesigned with new features, each book invites readers to discover the world of creatures that make their home in high places. Young learners will read about each animals unique physical characteristics, behavior, and adaptations to their environment. Through fascinating facts and brilliant photographs, these books paint a vibrant picture of the incredible array of animal life in the mountains.
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The Internet brought about a total revolution in the world of information. Today, anyone with an Internet connection can access a wealth of information online. As our access to data increases, copyright laws struggle to keep up. This book examines how copyright law has been applied to online content, the emerging open source movement, fair use, proper citation practice, and the ethics of using and citing online information. It is an invaluable resource for today's students.
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This is a well-organized look as coastal regions: what shapes them, some environmental threats, and their usefulness in industry and tourism. Several beautiful and interesting coastlines are highlighted, including Cancun and the Great Barrier Reef. Readers will learn about each coastline's location, population, local industries, and environmental threats.
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Chemistry is often a daunting subject for students, fostering a bewilderment that sets in upon their first encounter with the Periodic Table. This book demystifies an important aspect of the subject--chemical reactions--and demonstrates exactly how fascinating and fun chemistry can be. Starting out by explaining just what a chemical reaction is--and what it isn't--the book details in accessible language the various kinds of chemical reactions that are possible. It draws upon readily comprehensible everyday examples, like rusting metal, baking bread, battery power, digestion, rotting eggs, and burning candles. The book then turns to a survey of the history of chemical research, beginning in the Ancient and Classical Worlds, progressing to the Medieval alchemists and Renaissance innovators, and ending with the leading lights of modern chemistry. Readers will be introduced to luminaries such as Antoine Lavoisier, John Dalton, Louis Pasteur, Dmitri Mendeleyev, the Curies, and Ernest Rutherford. It concludes with an inspiring examination of how current research and cutting edge developments are using chemistry and chemical reactions to save lives and insure continued life on Earth. This book amply illustrates the accessibility, relevance, and gee-whiz fun of chemical reactions.
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The spread of harmful chemicals and biological organisms can injure and kill thousands of people and make an infected area unlivable for some time to come. In the age of modern terrorism, many people fear militant organizations will unleash chemical and biological weapons in public places. This book provides readers with an overview of what these weapons are, who uses them and why, and explains how much of a threat they are to our way of life. Over time, countries have pledged to ban the use of CBWs in various agreements, with limited success.
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Imagine traveling at half the speed of a jet plane without ever leaving the ground! Students will discover the technology that makes such speeds possible, from special tracks and safety precautions to aerodynamically designed trains. What are the limits to the speed of trains? What imposes those limits? Students also will read about the future of passenger train travel, from flying trains to trains that use huge magnets to levitate inches or centimeters off the track. Some trains safely reach speeds of more than 200 mph!
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Sin stockLuis loves to read, but soon his house in Colombia is so full of books there's barely room for the family. What to do? Then he comes up with the perfect solution: a traveling library! He buys two donkeys, Alfa and Beto, and travels with them throughout the land, bringing books and reading to the children in faraway villages. Beautiful!
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The detailed illustrations and photographs in this fascinating book take us into the complicated, hectic world of the beehive, where we observe the rigidly structured "class system" of the honeybee, with its worker bees, drones, and queen. The complex body and internal systems of the bee are examined, as the history, honey production, construction of the honeycomb, reproduction, and colony building are discussed.
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As the world's population expands, so too does the risk of communicable disease and global pandemics. Consequently, healthcare has assumed a greater centrality in the public consciousness both in the United States and around the world. With various national and international organizations dedicated to epidemiological research and disease control, societal welfare has become an increasingly significant aspect of public policy. The historical, legal, and scientific factors that form the basis of public health locally and globally are the subjects of this relevant and revealing volume.
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Artificial Intelligence is one of the most intriguing and difficult technological advances ever explored by man. It is the study of intelligent behavior and the attempt to recreate it through technology. This beginner's guide explores, not only the technology behind AI, but the current and future benefits of further exploration.