To see the impossibility of the evolutionist scenario on the marine mammals, let us briefly examine some other unique features of these animals. When the adaptations a land-dwelling mammal has to undergo in order to evolve into a marine mammal are considered, even the word "impossible" seems inadequate. During such a transition, if even of one of the intermediary stages failed to happen, the creature would be unable to survive, which would put an end to the entire process. The adaptations that marine mammals must undergo during the transition to water are as follows:
1- Water-retention: Unlike other marine animals, marine mammals cannot use sea water to meet their water needs. They need fresh water to survive. Though we have limited information about the freshwater resources of marine mammals, it is believed that they feed on organisms containing a relatively low proportion of salt (about one third that of sea water). Thus, for marine mammals the retention of water in their bodies is crucial. That is why they have a water retention mechanism similar to that of camels. Like camels, marine mammals do not sweat; however, their kidneys are perfectly functional, producing highly concentrated urine that enables the animal to save water. In this way, water loss is reduced to a minimum.
Design for water retention can be seen even in minor details. For instance, the mother whale feeds her baby with a concentrated form of milk similar to cheese. This milk contains ten times more fat than human milk. There are a number of chemical reasons why this milk is so rich in fat. Water is released as the young whale digests the milk. In this way, the mother meets the young whale's water needs with minimum water loss.
2- Sight and communication: The eyes of dolphins and whales enable them to have acute eyesight in different environments. They have perfect eyesight in water as well as out. Yet most living things, including man, have poor eyesight out of their natural environments.
The eyes of marine and land-dwelling mammals are astonishingly elaborate. On land, the eyes face a number of potential dangers. That is why the eyes of land-dwelling animals have lids to protect them. In the ocean, the greatest threats to the eye come from the high level of salt and the pressure from currents. To avoid direct contact with the currents, the eyes are located on the sides of the head. In addition to this, a hard layer protects the eyes of creatures which dive to great depths. The eyes of marine mammals are equipped with elaborate features enabling them to see at depths where there is little light. For example, their lenses are perfectly circular in shape, while in their retinas, rods (the cells sensitive to light) outnumber cones (the cells sensitive to colours and details). Furthermore, the eyes of cetaceans also contain a phosphorus layer, which also helps them see particularly well in the dark.
Even so, however, sight is not most important sensory modality of marine mammals. They rely more on their sense of hearing than is typically the case with land-dwelling mammals. Light is essential for sight, whereas hearing requires no such assistance. Many whales and dolphins hunt at a depth where it is completely dark, by means of a sonar mechanism they possess. Toothed whales, in particular, "see" by means of sound waves. Just as happens with light waves in the visual system, sound waves are focused and then analyzed and interpreted in the brain. This gives the cetacean accurate information regarding the shape, size, speed and position of the object in front of it. This sonic system is extremely sensitive-for instance, a dolphin can sense a person jumping into the sea. Sound waves are also used for determining direction and for communication. For example, two whales hundreds of kilometers apart can communicate via sound.
The question of how these animals produce the sounds that enable them to determine direction or to communicate is still largely unresolved. As far as we know, one particular feature in the dolphin's body deserves particular attention: namely, the animal's skull is insulated against sound, a feature that protects the brain from continuous and intensive noise bombardment.
Let us now consider the question: Is it possible that all these astonishing features in marine mammals came into existence by means of natural selection and mutation? What mutation could result in the dolphin's body's coming to possess a sonar system and a brain insulated from sound? What kind of mutation could enable its eye to see in dark water? What mutation could lead to the mechanism that allows the most economic use of water?
There is no end to such questions, and evolution has no answer to any of them. Instead, the theory of evolution makes do with an unbelievable story. Consider all the coincidences that this story involves in the case of marine mammals. First of all, fish just happened to come into existence in the water. Next, they made the transition to land by pure chance. Following this, they evolved on the land into reptiles and mammals, also by chance alone. Finally, it just so happened that some of these creatures returned to the water where by chance they acquired all the features they would need to survive there.
Can the theory of evolution prove even a single one of these stages? Certainly not. Far from being able to prove the claim as a whole, the theory of evolution is unable to demonstrate how even one of these different steps could have happened.
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