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it chock full of photographs and illustrations because, well, words alone don’t do the ocean justice, and because we’re fortunate to have generous friends who are some of the most amazing photographers in the world and were willing to give us access to their archives.

      Perhaps even more important is that we want to convey the vital role the ocean plays in humanity’s survival; even if you live in the middle of the desert, the ocean still affects you and your quality of life. Unfortunately, the ocean is taking the brunt of humanity’s ecological abuses, which spells trouble for all of us. The good news is that each and every one of us has the power to save it. By working together to stop and perhaps even reverse the damage we’ve caused while optimizing our use of the ocean’s vast resources, we can return the ocean to abundance. Our intent isn’t to be Debbie or Danny Downer. Our goal is to have fun, engage you, and maybe even recruit you to join the cause of loving and protecting the sea.

So, tighten up your swimsuit, strap on your scuba gear, and get ready to dive into what we feel is the most fun and fascinating of topics, the ocean.

About This Book

      Welcome to Oceans For Dummies. In this book, we serve as your personal tour guides to Earth’s watery wonderland. We lead you on a journey from shore to open ocean and from surface to seafloor, examining the ocean from multiple perspectives — its history, biology, ecology, economy, and much more. Along the way, we hope to expand your appreciation and general understanding of the ocean and its inhabitants. We also hope to increase your awareness of the opportunity to interact with the ocean in mutually beneficial ways, so we can all enjoy its vast resources while preserving it for future generations.

      To make the content more accessible, we divided it into the following six parts:

       Part 1, “Getting Started with Your Ocean Voyage,” touches on key topics covered throughout the book, highlights the many ways the ocean enhances our lives, and traces the origin of the ocean and the evolution of marine life (yeah, all that in three short chapters).

       Part 2, “Finding Your Way Around,” divides the ocean into zones and ecosystems (communities of interdependent marine organisms) and takes a deep dive to the seafloor to scope out what’s on, in, and below it — you may be surprised.

       Part 3, “Sampling the Vast Diversity of Sea Life,” consumes a vast majority of the book because, frankly, it’s the topic we find most fun and fascinating. Here, you meet shrimp that can smash open aquarium tanks with their bare knuckles; the brainy octopus, which can twist the lid off a jar using its suction-cupped grip (very handy in the kitchen); the largest creature on the planet, ever, which feeds on the smallest of prey; and numerous other creepy, freaky, and awesome characters.

       Part 4, “Grasping Basic Ocean Physics,” looks at the ocean as a part of an integrated system comprised of water, land, atmosphere, the sun, the moon, and certain physical forces that make Earth what it is. In this context, we explain how water, heat, and nutrients are circulated around the ocean and around the globe and how the ocean helps to regulate climate and drive weather.

       Part 5, “Understanding the Human-Ocean Connection,” focuses on the many ways the ocean benefits our lives, how the exploitation of its resources are governed, and how we humans need to transition our relationship with the ocean from one of dependence to interdependence to fully enjoy its benefits while preserving its health. In this part, we also dip into the topic of ocean exploration — showcasing the innovations and technologies that have driven its development over the last couple hundred years.

       Part 6, “The Part of Tens,” features three “top ten lists” — the ten deadliest sea creatures, ten ocean myths we bust wide open, and ten easy ways you can help to preserve the ocean for future generations.

      In short, this book serves as your guide to almost everything about the ocean in a fun and accessible way. And while some of these subjects deserve an entire book for themselves (hello, nudibranchs!), we worked hard to find the balance between breadth and depth.

Foolish Assumptions

      All assumptions are foolish, and we’re always reluctant to make them, but to keep this book focused on the right audience and ensure that it delivers the information and insight you need to grasp a topic as broad as the ocean, we had to make the following foolish assumptions about you:

       You’re curious about the ocean and eager to discover more about it.

       You’re mostly interested in marine life, such as turtles, sharks, and dolphins and ecosystems, such as coral reefs and kelp forests.

       You’re concerned about the health of the ocean, and you want to find out more about what can be done, what’s being done, and what you can do to help the ocean thrive.

      Other than those three foolish assumptions, we can honestly say that we can’t assume much more about you. For all we know, you could be a precocious 4-year old or a spirited octogenarian, you may be a student, a white collar or blue collar worker, a housewife or househusband, a doctor, a lawyer, a plumber or a construction worker. You could be living on an island, a coast, deep in the Amazon jungle, or on a farm in the middle of Iowa. Regardless of your demographic, we applaud your interest in the ocean and your eagerness to expand your knowledge and understanding of Earth’s most precious blue gem.

Icons Used in This Book

      Throughout this book, icons in the margins highlight certain types of valuable information that call out for your attention. Here are the icons you’ll encounter and a brief description of each.

       We want you to remember everything you read in this book, but if you can’t quite do that, then remember the important points flagged with this icon.

The ocean is full of surprises both entertaining and mind blowing, and we don’t want you to miss any of them, so we use this Fun Fact icon to flag every single one.

       We don’t advise you to do anything very dangerous in this book so you won’t bump into many of these warning icons. In fact, we even try to alleviate any fears you may have about potentially dangerous marine creatures like big bad sharks (ooohhh), jellyfish, and sea snakes. Most of what you read in the news and see in the movies is way overblown. However, we did have a couple opportunities to use this icon, so watch out for it.

Beyond the Book

      In addition to the ocean of information and insight we provide in this book, you have access to even more help and information online at Dummies.com, including a Cheat Sheet that serves as a quick reference guide to this book. We also posted a list of our ten favorite sea creatures — a bonus item that truly goes “beyond the book.” To access the Cheat Sheet, go to www.dummies.com and search for “Oceans For Dummies Cheat Sheet.”

Where to Go from Here

      You’re certainly welcome to read this book from cover to cover, but we wrote it in a way that facilitates skipping around. For