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All About the EYE Written by Marie Kotasová Adámková All About Illustrated by Matej Ilčík

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All About the EYE Written by Marie Kotasová Adámková All About Illustrated by Matej Ilčík Marie Kotasová Adámková Marie Kotasová Adámková Matej Ilčík All about THE EYE Written by Marie Kotasová Adámková All about Illustrated by Matej Ilčík Eyes are windows to the soul, they say. And there are THE EYE as many kinds of eye as there are kinds of window. The book All About the Eye gives you a unique opportunity to investigate these ‘windows of the soul’ B4U PUBLISHING and to discover how they evolved and how they have affected the lives of their owners. You will travel across continents, as the book contains a large-format map THE EYE showing where eyes described in the book come from. So, open your eyes wide and read carefully. If you read every word and study every illustration, you will soon know all about the eye. All about www.albatrosmedia.eu RHOPALIUM → Stinging creatures SEA WASP IN ADDITION TO JELLYFISH, THE CNIDARIA GROUP COMPRISES EXTREMELY MANY STUNNING ANIMALS. POISONOUS Chironex fleckeri TENTACLES ↓ he faraway tropical Interesting Twaters are inhabited by TWENTY FOUR EYES an inconspicuous but deadly ALL OVER WHOLE ↑ animal. What makes it even BODY RHOPALIUM IS A CLUSTER more dangerous is the fact it OF SIX EYES can be easily overlooked by an incautious swimmer: the body of up to 25 cm and the sixty SEEING ABOVE stinging tentacles of up to three PORTUGUESE MAN O’WAR metres are semi-translucent. THE SURFACE Beware of them as the venom The sea wasp has a total of twenty-four of Chironex fleckeri, also different eyes on its body. Eight of them are known as the sea wasp, is one outer eyes with a diameter of only a tenth of of the strongest venoms in the a millimetre and are similar to the perfect eyes world. It can kill a man in only of vertebrates: they consists of retina, lens, iris two minutes! and cornea. Scientists have wondered for years how the perfect eyes of sea wasps evolved and what their purpose was. We know today RED CORAL that sea wasps use their vision to look for stilt mangrove roots, where they live in dry seasons. The roots are full of shellfish on which the sea 3 m RHOPALIUM wasp feeds in mangroves. The outer eyes help the sea wasp see the world above the surface Cnidarian eyes are arranged in a special sense organ called the in a relatively large visual field. rhopalium. The sea wasp has four rhopalia, and each of them is Cnidaria composed of a cluster of six eyes. Two of them have an extremely fine lens, as mentioned above. The remaining six eyes of each PURPLE SEA FAN Indian and rhopalium are simple. As one can see, the sea wasp’s visual VISUAL FIELD → Pacific Oceans, skills are amazing! Jellyfish lack, however, one organ to achieve UP TO 100° Australia perfect image perception. Do you know which one? It is the ABOVE THE brain. Although it is difficult to perceive images with a simple SURFACE nervous system, nature dealt with this limitation as well. When rhopalia a jellyfish needs to move towards food, it is the rhopalium that triggers the body contraction and subsequent movement. RHOPALIUM → HYDRA VIRIDISSIMA 6 7 → → HIGHLY Disguised agents DEVELOPED COMMON CUTTLEFISH EYES THE ABILITY TO CHANGE THE COLOUR OF ITS BODY IS DUE TO THE PRESENCE OF SPECIAL Sepia officinalis 45 cm CELLS CALLED CHROMATOPHORES. he cuttlefish lives on the seabed of the ↑ Mediterranean Sea and the eastern T COLOUR CHANGING Atlantic. This cousin of the octopus ranks Cephalopoda SKIN among the perfect sea predators! It hides in the sand during the day and becomes active when the evening begins: Mediterranean Sea, SEA CHAMELEON it waits at the sea bottom, looking for eastern Atlantic One of the most important characteristics of a good potential prey, which it then slowly predator is the ability to be inconspicuous. If the prey approaches. Once the prey is within saw the hunter from afar, it would have plenty of time ↑ reach of the tentacles of the cuttlefish, COMMON OCTOPUS it perceives to flee to safety, and the hunter would go to bed on an EYE ADAPTED TO two long arms with suckers spring up and polarized light empty stomach. The cuttlefish has developed an amazing SEE POLARIZED grasp it in a flash. The strong beak-like LIGHT camouflage tactic to confuse both potential food and jaws quickly kill the prey and the feast larger predators. It can change not only its colour but may begin. also the pattern and structure of its body surface! It also has spots comprised of cells reflecting light on its body. UNSUSPECTING They can shrink or enlarge and form an image similar SECRET SIGNAL PREY to large eyes to discourage larger predators. There is Under its colour cells, the cuttlefish has ↓ a good reason for calling cuttlefish “sea chameleons”! EUROPEAN TREE FROG a special “grid” reflecting polarized light. The reflected light is thus dispersed into Interesting HIDDEN CUTTLEFISH the surrounding area and remains invisible IT SPRAYS INK WHEN to most animals. But it is perceived by the IN DANGER ↓ cuttlefish! The cuttlefish has highly-developed eyes similar to yours which are specially adapted to see polarized light. This secret signal helps them remain unseen by other animals and keep track of their relatives. PANTHER CHAMELEON Even when they are perfectly camouflaged. What if a larger predator encounters them by accident? The cuttlefish releases ink which briefly paralyses the enemy and disguises the cuttlefish. SEABED → PRAYING MANTIS 12 13 up to 18 cm PEACOCK MANTIS SHRIMP → STALKS MOVE EYES ON → INDEPENDENTLY MOBILE STALKS Odontodactylus scyllarus Crustacea antis shrimp has distinctive eyes mounted on Pacific and Mmobile stalks, enabling it to cover a large visual Indian Oceans field. They can even move independently of each other! Perfect spatial vision is essential to the mantis shrimp. Another interesting fact is the number of photosensitive cells in the mantis shrimp’s eyes: while a man has three most cell types in the eye types of photoreceptors, the mantis shrimp has twelve ↑ of them! It can thus perceive ultraviolet and polarized IT HIDES ↑ light. Like cuttlefish, the mantis shrimp uses polarized IN ROCKS FAST CLAWS EYES WITH light for intraspecies communication. Do you want to know what the mantis 12 PHOTORECEPTORS shrimp feeds on? Its prey consists mainly of various crustaceans, CORAL REEF molluscs and small fish. The mantis ↓ PRAWN KILLER → PREY IS shrimp first look around to find them STUNNED BY and then hunts them out of their shelter Although it may not appear to be likely at first FAST ATTACK with its massive claws. It hides in glance, mantis shrimp is one of the most savage various rock structures on coral reefs sea predators. It has even been nicknamed or in tunnels it digs in the seafloor. “prawn killer” based on its ferocity and When hunting, it takes advantage aggression. This crustacean with strong claws of its strength as well as its speed. is up to 18 cm long, but despite its size, can During an attack, the claws move at be immensely strong! This ironside has the most 23 m/s! Their prey is stunned and powerful blow of all animals in the world. The killed in a flash. mantis shrimp can even break the glass aquarium in which it is sometimes kept. Beware WHAT ANIMALS DO YOU THINK OF WHEN TALKING ABOUT THE MOST SAVAGE SEA PREDATORS? LEOPARD SEAL GREAT WHITE SHARK SALTWATER CROCODILE KILLER WHALE FANGTOOTH MORAY 20 21 PLAICE HIDDEN IN SAND Flatfish EUROPEAN PLAICE ↓ THE PLAICE IS NOT THE ONLY FLATFISH. A FLATTENED BODY WITH A SHIFTED EYE IS ALSO TYPICAL FOR FLOUNDERS, TURBOTS, COMMON Pleuronectes platessa 50 to 60 cm SOLES AND OTHER SPECIES. ALL OF THESE ARE CLOSELY RELATED TO → → PROTECTION THE PLAICE. FROM PLAICE ON Osteichthyes → → THE WATCH PREDATORS Europe EVOLUTION How does the plaice develop over the course of its life? The plaice hatches from eggs into common fry with a bilaterally symmetrical body. The young plaice is buoyed the left eye LEOPARD FLOUNDER moves to the by a swim bladder and floats freely. When the time comes to mature, it begins gradually leaning towards the seabed. he sandy or muddy bottom of European seas often harbours right side The plaice progressively loses its swim bladder, until it one inconspicuous species of fish, the European plaice. Its T completely lies on one side. Its diet also changes during disc-shaped body can be easily overlooked, which is to the benefit development. While the food of larvae consists of plankton of the plaice. After all, it is not very fast or agile. The body of the and larvae of other animals, the adult plaice feeds on plaice is flattened and coloured similarly to the seabed. In order various molluscs, sea worms, crustaceans and smaller fish. to bring the camouflage to perfection, the plaice lies on one side It hunts them with its mouth which, unlike the eyes, remains and often burrows into the sand. Since an eye directed into the Interesting oriented to the side. PLATE FISH sand would be no use, the left eye shifts to the right side of the head next to the right eye when the plaice transforms into an ALTHOUGH IT HAS ITS EYES ON ONE SIDE OF THE HEAD, adult. Moreover, its eyes bulge and can move independently of ITS MOUTH FACES each other. The plaice thus remains unnoticed, while cautiously TO THE SIDE monitoring the environment. FLATTENED → BODY TURBOT EYE SHIFTED TO THE RIGHT SIDE OF HEAD → → → SANDY SEABED COMMON SOLE 30 31 NESTING Birds of prey GOLDEN EAGLE Eagle its nest on high trees or inaccessible rocks.
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