How can dead skin cells float around

Sylvia Englert. Seas and oceans. With illustrations by Johann Brandstetter


1 Sylvia Englert Seas and Oceans With illustrations by Johann Brandstetter

2 cbj is the children's and youth book publisher in the Random House publishing group. Our sincere thanks go to everyone who supported us in answering the questions: Dr. Uwe Waller from the Leibniz Institute for Marine Sciences IFM-GEOMAR, Dr. Claudio Richter from the Center for Tropical Marine Ecology, Dr. Peter Ehlers from the Federal Maritime and Hydrographic Agency, Christof Goetze from the Wadden Sea Protection Station, Dr. Anselm Goertz, Dr. med Markus Bauer, Christian Münker and, above all, the editorial team of the »Sendung mit der Maus«, especially Hilla Stadtbäumer. Environmental note: This book was printed on paper that has been bleached without the use of chlorine. Set according to the rules of the spelling reform 1st edition cbj, Munich I. Schmitt-Menzel / WDR mediagroup licensing GmbH The broadcast with the mouse WDR license agency: BAVARIA SONOR, D Geiselgasteig All rights reserved Editing: Ulrike Hauswaldt Editor: Anette Reiter Photo editor: Tanja Nerger Cover picture and interior illustrations: Johann Brandstetter Cover conception: Init. Büro für gestaltung, Bielefeld Picture credits for interior photos: Ardea, London / England: 25o. (Ken Lucas); Bilderberg, Hamburg: 19 (Reinhard Dirscherl); Corbis Stockmarket, Düsseldorf: 42 (Jeffrey L. Rotman), 43 (Craig Tuttle); Gettyimages, Munich: 7 (Taxi / Peter Scoones), 15 (Photographer s Choice / Pete Atkinson), 25u. (National Geographic / Tim Laman), 51 (Stone / Bob Barbour), 53 (Stone / Mark A. Leman); Interfoto, Munich: 37 (Friedrich Archive); Mauritius picture agency, Mittenwald: 46 (Reinhard Dirscherl), 49 (die Kleinert); NASA / GSFC, Washington, DC / USA: 13 (Jacques Descloitres, MODIS Rapid Response Team); NHPA, London / England: 12 (M I Walker); Picture Alliance, Frankfurt: 50 (dpa report); Shipping Publications, Krohn Johansen Forlag, Larvik: 52 (BA Krohn Johansen) Mouse illustrations: Ina Steinmetz AR Production: Ina Hochbach Layout and typesetting: Sabine Hüttenkofer, Großdingharting Reproduction: Wahl Media GmbH, Munich Printing: TBB, Banská Bystrica ISBN Printed in the Slovak Republic

3 Contents Why is sea water salty? How did the fish get into the sea? Why do fish have scales? How does the ink get into the squid? Why do algae grow in the water? Why does it hurt when you touch a jellyfish? Where does the water go when the tide comes out? Why does nothing happen to clown fish in the anemone? Why do fishes never collide with each other in a school? Why do you hear the sea rushing in large seashells? Are Fish Really Mute? What are corals and how does a reef come about? Do fish have to drink? Why can you only see clearly underwater with diving goggles? How does a submarine work? What does it look like in the deep sea? How can fish breathe underwater? How many teeth does a shark have? How do dolphins sleep? Why can whales dive for so long? What is the difference between sea and ocean? How do waves arise? Who Owns the Sea? Mouse lexicon * Register * All terms highlighted in color in the text are explained in the mouse lexicon.

4 Why is sea water salty? North Sea water Baltic Sea water in liters of water from the open sea contains about three tablespoons of salt. Bad luck for castaways: You can't drink this without feeling sick or even more thirsty! To explain how the oceans became salty, one has to look far back into the history of the earth. Originally the earth was a glowing ball of rock on which numerous volcanoes spat fire. Gases, including water vapor, escaped from the molten rock. As the earth slowly cooled, huge clouds formed from it and it began to rain. It rained and rained, and not just for a few weeks, but for millions of years. Little by little, the oceans emerged from this water. North Sea water is much saltier than Baltic Sea water. Because the Baltic Sea is only connected to other seas by a narrow channel and receives a lot of fresh water from rain and rivers. Water evaporates and forms clouds. Initially, around four billion years ago, they were still made up of fresh water. But the heavy rain washed everything that could somehow dissolve, salts and many other substances, from the rock into the sea. This is why sea water contains almost a hundred different substances, including lots of salt. 4th

5 The open sea is always salty. How can that be after all, fresh water constantly flows in from rivers? The explanation lies in the water cycle. Rivers and rain thin out the sea water, but the sea also gives off water. When the sun hits the surface of the sea, water evaporates, rises into the air as vapor and forms clouds there. As rain, the water returns to the mainland (and thus into the rivers). In this way, the salt content remains in equilibrium and changes at most over the course of millions of years. Seas that have no access to the ocean and receive little fresh water from rivers, such as the Dead Sea between Israel and Jordan, for example, have a problem. The water there has already become so salty that fish can no longer live in it. This is how the sea got its name. The water falls on the earth as rain. In rivers, the water returns to the sea. The water cycle 5

6 How did the fish get into the sea? he life on earth originated in the sea and then slowly conquered the land. Fish evolved 490 million years ago long before the dinosaurs! It probably all started like this: In the deep sea, hot water, which contained many different substances, rose from the interior of the earth. The fabrics could have combined and changed. Many scientists believe that this is where the building blocks of life emerged. Individual cells, primitive algae and bacteria formed. It is believed that they evolved in tiny steps into more complex living things over many millions of years. They found different ways of obtaining food and adapting to their environment. As a result, more and more species of animals and plants populated the young earth. Before fish were created in this way, there were sponges, corals and many armored animals with legs, the arthropods. If you had pulled a net through the water back then, there would have been a few trilobites in it. There were very many of these arthropods. Protozoan jellyfish Anomalocaris sacabambaspis (first fish) Pikaia Trilobite tunicate Hallucigenia 3.5 billion years ago Cambrian million years ago Ordovician million years ago

7 The first fish looked almost like they do today. Only they had no jawbones, but a round, fleshy mouth. In addition, the bodies of some fish were heavily armored. This is how they protected themselves against enemies. It became particularly dangerous for fish in the age of the dinosaurs. Back then, they were hunted by marine dinosaurs that looked like dolphins. It is likely that close relatives of the coelacanth were the first to venture ashore. Marine dinosaurs Many animals that once populated the oceans have disappeared again. For example the trilobites. But a very, very old species of fish still exists today. For a long time, scientists thought that the coelacanth was extinct. He was only known from fossils. Until fishermen pulled one of these animals out of the water in South Africa in 1938! The coelacanth has firm front fins with which it can "walk" over the ground. Some species could probably even breathe air like us. Cladoselache (formerly shark) Eusthenopteron (first landwalker) Dunkleosteous (armored fish) Hemicyclaspis (jawless fish) Lungfish Belemit (primeval squid) Devonian millions of years ago

8 Why do fish have scales? Aren't fur or bare skin just as practical? Not really! There are fish that have a skin without scales. For example sharks or rays. And for marine mammals like seals, a warm coat is useful. But most fish have scales because they offer the greatest advantages. The scales seal the body against the water. They give the fish body greater strength. Even so, they do not hinder the fish from swimming. 3. Fish scales lie on top of each other like roof tiles. Originally they were also a protection against enemies. How the scales have developed can be seen in fish that have been around for a very long time, for example the sturgeon. His body is armored with bone plates like a knight in armor. At this sight, every predatory fish loses the desire to bite! The sturgeon, which is up to eight meters long, has no scales, but rather bone plates. 8th

9 Today most fish have smaller scales. But they also protect against abrasions on stones and plants. Fish scales are made from a material similar to our fingernails. They also contain lime. That makes them firm and flexible at the same time. If you've ever touched a fish, you've probably noticed that it feels slimy. This layer of mucus over the scales is a protective layer against harmful bacteria. It is constantly being regenerated so that the bacteria are shed off. Shark's skin teeth Researchers can use the scales of a fish to determine how old it is. With a magnifying glass or under a microscope, they count the many small rings that can be seen on the scales. Each ring stands for one year. Sharks don't feel slimy, they feel rough like sandpaper. Your skin is covered with many tiny teeth. The predatory fish use these teeth when hunting: a curious shark first roams past possible prey. He rasps off a small sample. He can use sensory cells in his skin to determine how the prey tastes and whether it is worth biting into. 9

10 How does the ink get into the squid? It would be funny to see squids crawling into the stationery store and buying more ink cartridges. Tentacles arms eyes brain But these snail-related mollusks don't need that at all. Schulp (a light bowl that helps him swim) Stomach Sex cavity with ovary Ink pouch Suction cups Mouth (beak) Mantle Gill Mantle cavity Heart The body of a squid They produce their ink themselves with special glands and store it in a paint bag in their body. The ink consists mainly of the dye melanin. Humans also have this substance in their body, it gives us the color of our skin and hair. When an octopus or octopus (both of which are cephalopods) has to flee, it empties its ink bag. The pursuer literally goes blank. Only in the pitch-dark deep sea does this not work. The species of octopus that live there emit a cloud of glowing liquid when threatened. That confuses enemies. Then the octopus tries to escape. Mostly he crawls or walks on his eight arms on the seabed. 10

11 But he's also a skilled swimmer. He takes water into his body cavity through an opening and quickly presses it out again. It is already whizzing away like a rocket! The octopus prefers to hide in caves to hide. There his soft, boneless body is protected from enemies. In peace and quiet, he can crack crabs and mussels with his powerful, beak-like mouth or lurk for fish swimming by. Even when octopuses come out of their cave, they are hard to spot. Because octopuses are quick-change artists. Its color adapts to the surface in a flash. This works through superimposed color cells in your skin that can expand or contract. Together they then result in the necessary pattern.

12 Why do algae grow in the water? It's bewitched: Even in a clean glass of water, algae will grow after a few days! That's because tiny algae are floating around in the air all over the place. If an alga lands in the water, it immediately begins to divide. It multiplies at a rapid pace. But what is a nuisance in the swimming pool or aquarium is a blessing in the sea. Because without algae there would be no fish! The tiny types of algae that float in the sea are called the plant plankton. Many tiny animals, the animal plankton, feed on it. The sea food chain: This is what diatoms look like under the microscope. It is eaten by small fish, which in turn feed larger fish and seabirds. The larger fish are the prey of dolphins, sharks and other large predators of the seas. But there are also large sea creatures that feed directly on plankton, whale and whale sharks. Shrimp eats green algae Sardine eats shrimp Grouper eats sardine Tiger shark eats grouper Some types of seaweed contain gas bubbles so that they can swim better on the surface of the water. In addition to plankton, there are also many larger algae called seaweed. Tang has no roots and no real leaves.

13 But seaweed contains leafy green, just like land plants. This allows him to feed himself with the help of sunlight. What additional nutrients it needs, it does not get from the soil, but from the water. When algae bloom, algae multiply very quickly. This makes the water cloudy and "cloudy". The algae can also be poisonous and pose a threat to living things in the water. The largest species of tang is the kelp. Kelp can grow to be forty feet long and grows incredibly quickly. 50 centimeters every day! Of the land plants, only bamboo can do that. Although you may have heard of an "algae bloom", algae do not bloom. They have no flowers at all. It is only called "bloom" when algae grow particularly well somewhere (usually in spring or summer). Such colorful carpets of algae can even be seen on satellite images of the sea. This is where whales and schools of fish hold true feeding orgies. 13th

14 Why does it hurt to touch a jellyfish? hen you've touched a nettle before, you can imagine what it's like to touch a jellyfish. The arms of many species of jellyfish are covered with tiny, poison-filled nettle capsules. If you touch them, they will shoot you! A thread jumps out of the nettle capsule with thorns on it. These thorns pierce the skin like a small harpoon, allowing poison to enter the body. Stomach cavity Mouth arms Umbrella Nettle capsule How painful this is depends on the type of jellyfish. The ear jellyfish, which is common in Europe, is harmless to humans. But there are also fire jellyfish and nettle jellyfish in the North and Baltic Seas, the skin of which burns violently. By the way, it helps to put vinegar on the wound. In the case of major injuries, however, you have to see a doctor. There are even more unpleasant jellyfish in warmer waters: you should avoid the Portuguese galley, for example. The best thing to do is to really widen it. Their umbrella is only a foot tall, but their dangerous tentacles can be 50 meters long. The poison is useful for the jellyfish because it can paralyze small prey such as fish, crabs and worms. But most of all, it serves them as a weapon. Jellyfish cannot move very quickly and most of the time they just drift with the current. Without the poison, they would be eaten quickly. But because they can defend themselves so well, they hardly have any enemies. Only the thread snail dares to approach them. You don't mind the nettle poison. Thread worm 14

15 Earthen jellyfish Fire jellyfish The crowned jellyfish lives in great depths and is perfectly adapted to its dark environment: it glows from within. Portuguese galley The state jellyfish, to which the Portuguese galley belongs, are particularly fascinating. You are not an individual. Each of these jellyfish consists of a multitude of animals that have fixed tasks. Some specialize in procuring food, others in procreation or defending the state. All these animals called polyps did not decide that they want to live in the jellyfish. They arose out of it. Like buds on a plant, new polyps keep growing inside the jellyfish. 15th

16 Where does the water go when the tide comes out? The best way to answer this question is to take a bath. Then you move up and down a little so that the water billows back and forth. You can imagine the ebb and flow of the tide as a single, flat wave. The water does not go away, it just sloshes towards the open sea. It sloshes back a few hours later. The moon is responsible for this. Its mass draws the water of the oceans towards itself. The part of the earth over which the moon is currently experiencing a flood, as is the exactly opposite side. The rest of the world is out of tide. Since the earth rotates once every 24 hours, the ebb and flow of the tides (the so-called tides) alternate about every six hours. Sand eel moon jellyfish limpets clam Tell mussel periwinkle lugworm

17 Starfish Mussels Swimming Crab Cockle The coast is a very difficult habitat for marine animals. Sometimes there is water, then again there is not, you get constantly slapped by waves and when it rains heavily you suddenly find yourself sitting in fresh water, yuck!

18 Oystercatchers Limpets, Clam, Tellmuschel, lugworm

19 Moon ebb flood flood Earth ebb North Pole 6 hours later But why do some seas have ebb and flow and others apparently not? Quite simply: In oceans like the Atlantic, gigantic masses of water can move back and forth. On their coasts, the difference between ebb and flow (called the tidal range) is several meters.The Mediterranean or the Baltic Sea are tiny in comparison. There just can't be so much sloshing around here! A few animals have learned to deal with these conditions. Mussels and limpets attach themselves to rocks and close their shells when the water disappears. This is how they prevent their bodies from drying out. Clams and clams dig themselves into the damp sand and only come out at high tide. Herring Gull Curlew Periwinkle Mussels Cockle You can tell that a lugworm lives under the sand by the small, spaghetti-like piles of sand that lie around at low tide. The worm eats sand, digests tiny parts of the plant and excretes the rest.

20 Why does nothing happen to clown fish in the anemone? e anemones look like plants, but they are animals. And similar to jellyfish, they have dangerous tentacles. But clownfish and other species of anemonefish that live in tropical reefs literally cuddle between the poisonous arms. Their secret lies in the layer of mucus around their bodies. Anemonefish can absorb the poison of the anemone into their outer skin layer. When a clownfish wants to get to know a sea anemone, it first carefully hugs individual tentacles. Then he strokes them with his head and stomach. After all, his skin is adapted to the anemone and he can completely immerse himself in his new home. Anemone clownfish butterflyfish are one of the few animals that find sea anemones tasty. Butterflyfish

21 sea anemones can live to be over a hundred years old! So they offer protection to several generations of residents. Because anemonefish only live about ten years. For the anemone the little fish is now like a part of itself. From now on it can live in it, even sleep inside it. None of his enemies dares go anywhere. In return, the clown fish protects "his" anemone from voracious butterfly fish. In addition, its excretions act like a fertilizer on the anemone. Inhabited anemones grow faster and live longer. Such partnerships, in which both sides have advantages, are called symbiosis. Another example is the services of cleaner fish and shrimp. At certain "cleaning stations" a fish only needs to wait motionless and spread its fins and gills. Cleaner fish are already rushing over and eating pests and dead skin cells from its body. They can even swim into the open mouth of the "customer" without being eaten. Once the fish has been cleaned, it swims away satisfied. The cleaner fish are also satisfied because they are full. A small striped cleaner fish at work 19

22 Why do fishes never collide with each other in a school? he sea is a very different environment than the one in which we live. Under water, where you can often not see far, eyes and ears are not enough. That is why fish have developed more sense organs than we do. One of these is the lateral line organ. It is thanks to him that schools of fish do not become a mess. The lateral line organ consists of sensory cells along the midline of the body. With this, the fish perceives how strongly the water is pressing against its body. When another animal approaches, the water pressure changes. The fish feels this immediately. Schooling fish such as herrings or anchovies use this organ to effortlessly obey the laws of the school. The most important of these is: Always stay at the same distance from your neighbor! Since every fish obeys this rule, the movements of the school look like a dance. There is no leader in the swarm. Every single herring can be the one who shows others how to do it. Of course, it makes sense why thousands of pegs make sure to stay nice and close together. It's easier to live together. Since schooling fish look very similar, it is difficult for predatory fish to select and hunt a particular one as prey. The fish are constantly on the move and confuse the enemy. As a result, the individual animal in the swarm has a higher chance of survival. Lateral line organ The sensory cells are located under small holes in the scales. 20th

23 NON-SELLER READING SAMPLE Sylvia Englert Just ask ... the mouse! - Meere und Ozeane Hardcover book, paperboard, 56 pages, 20.0 x 24.0 cm ISBN: cbj Date of publication: October 2007 When children ask questions and adults don't know what to do next, it means: Just ask ... the mouse! In almost every family, the well-known factual stories have had a special status for 35 years: not only children, but adults too, watch with fascination when the world is explained in the MAUS. The show with the mouse is a classic with cult status! The principle of success of the show with the mouse is to take questions from children seriously and to deal with them intensively. This is also what the non-fiction series does: simple and astonishing children's questions arouse interest in complex issues, which are then explained step by step in a playful, factually based and always child-friendly way. HOW DID THE FISH GET INTO THE SEA? Children have countless questions about the sea and the ocean: Why do you hear the sea rustling in large shells? Or: Are there really monsters in the depths of the oceans? The mouse knows the answers and reports the latest from deep-sea research! Fold-out panorama pages reveal the fascinating flora under water; Foil pages make the cycle of the tides visible and the poster reveals which depth zones the sea is divided into and where which animals live! The most mysterious habitat on our planet is wonderfully presented and explained with great care! And that is what every volume offers: All the key topics that children are particularly interested in Answers to the most important children's questions Carefully researched factual information from renowned authors Facts are explained step by step Information and child-friendly illustrations by successful illustrators as well as numerous photos support the texts The close cooperation with MAUS EDITORIAL guarantees the quality and originality of the factual texts. High-quality equipment: Numerous extras underline the playful character