No Evidence for Shark Evolution
No sea animal elicits such fear and terror in the common people as do sharks. Gruesome shark attacks on humans are part of both the folklore and history of many cultures, including our own. Their predatory skill both fascinates and frightens us. Even though sharks rarely attack humans, when an attack occurs, it tends to be widely publicized by the mass media. Ironically, their very survival is now threatened by human-related activities, such as net fishing.
Sharks (superorder Selachimorpha) are a type of fish with a skeleton made of cartilage instead of bone, and a highly streamlined body. The eight orders of sharks are found in all oceans (Taylor et al. 1995 Sharks: Silent Hunters of the Deep. Readers Digest p. 8) and are common down to depths of about 2,000 meters (6,600 ft). Most sharks live in saltwater, although some, such as the bull and river sharks, can survive in both seawater and freshwater.
Well-known species include the great white shark, tiger shark, the bull shark and the hammerhead shark. The 440 known shark species range in size from the tiny 100 mm long (4 in) dwarf lantern shark, to the largest known shark, the whale shark, that can grow up to 14 meters (46 ft) long (Barraclough, Susan (editor). 2007. Sharks and other Creatures of the Deep. Sandy Creek, N.Y p. 33). Sharks are all predators, at the top of their underwater food chain. Their diet ranges from plankton to seals. The whale and megamouth sharks are filter feeders that consume plankton, jellyfish, squid, and small fish.
Sharks are expertly designed for speed and supple movement. Their smooth-skinned streamlined body allows them to rapidly traverse their watery world while saving energy (Barraclough. p. 6). Sharks are covered, not by scales as are most fish, but by dermal denticles that are very small versions of teeth. These not only protect their skin from damage and parasites, but also greatly improve their fluid dynamics. If you stroke a shark backwards, from its tail to its head, the hard denticles can scrape your skin severely enough to cause bleeding (Walters, M. and J. Johnson. 2011. The World of Animals. Master Books p. 104). The origin of dermal denticles has baffled evolutionists because no evidence of transformation of small teeth to body covering has been discovered in the fossil record, or even postulated, even though dermal material preserves very well in the fossil record.
Sharks, skates, and rays all have cartilage and connective tissue skeletons instead of bone. It is for this reason that they are considered “primitive” life forms by evolutionists in spite of the fact that they have many of the very highly complex organ systems, such as their advanced sensory organs described below that are typical of very advanced animals.
Their putative primitive cartilage skeleton has clear design advantages for a shark’s way of life, such as greatly reduced weight. Cartilage has other advantages over bone, such as being flexible, durable and strong, yet about half the density of bone. Sharks also lack a rib cage and, therefore, a shark’s own weight can crush it on land but in water it is perfectly balanced.
Sharks are not primitive fish; most have a keen sense of smell, and excellent eyesight. They have a highly complex retina, part of a very advanced vision system very much like that of humans (Taylor et al. p. 34). They also have a highly specialized mouth and several sets of replaceable teeth.
They can sense small vibrations in the water and target their prey by electric sensors located around their snouts (Barraclough. p. 9). In the late 1970s it was discovered that sharks have a sixth sense that operates in turbid water, total darkness, and even when its prey is beneath the ocean floor (Fields, R. D. 2007. The Shark’s Electric Sense: An Astonishing Sensitive Detector of Electric Fields Helps Sharks Zero in on Prey. Scientific American 297 (2): 75-81.). It consists of electrosensors, part of a well designed complex system that can sense extremely weak electric fields with thousands of specialized sensitive detectors sending a message like vision to the brain, allowing them to “see” prey.
Some sharks have wide-angle vision to obtain a panoramic view of their environment. The hammerhead shark has two widely spaced eyes that produce excellent binocular vision that serves as a range finder to accurately determine the distance to objects (Barraclough. p. 34).
For many other reasons, sharks are one of the most efficient, as well as most deadly, hunters known (Barraclough. p. 9). They are also very intelligent as we would expect from their large brain –– some have a larger brain in proportion to body weight than most so-called more advanced bony fishes, many birds, and even some mammals (Taylor et al, p. 21).
Evolutionists date the earliest known sharks back to about 420 million years ago (Long, John A. 1995. The Rise of Fishes: 500 Million Years of Evolution. John Hopkins University Press. p. 70). The Port Jackson Shark, Haterondontus japonicus, has remained unchanged for 181 million years, according to evolutionists. Likewise, evolutionists have dated the cow shark back to 166 million years ago and the cat shark back to 136 million years. As far as can be determined, all known fossil examples of sharks are very similar to modern sharks, and sharks have shown no evidence of evolution. Werner shows several examples of Dinosaur-Era sharks that are identical to modern sharks (2008). For this reason they are often called living fossils. Professor John Long, head curator of vertebrate paleontology at Western Australian Museum, concluded that the
Origins of sharks are still a mystery. Some scientists regard sharks as the most primitive of all the jawed fishes, whereas others see them as highly specialized forms that did not require the complex bony ossifications of other fish groups (Long. p. 69).
Although the “early evolutionary history of sharks and shark-like fishes is still poorly understood” shark fossils are found as far back as, according to evolutionists, 420 million years ago (Taylor et al. p. 38). Professor Long also contends that sharks and other “jawless fish alive today are essentially unchanged from those living at the time of the dinosaurs” (Werner, Carl. 2008. Living Fossils. New Leaf Press p. 126). The current theory of shark evolution includes the speculation that they are
closely related to the now-extinct placoderms, and both these groups may have arisen from a scale-covered jawless form well before the Early Silurian. The presence of shark-like scales of this age, and their striking similarity to the scales of the jawless thelodonts, has lead some workers to suggest that thelodonts and sharks could be close relatives, and the recent discovery of the remarkable fork-tailed thelodonts from Canada would seem to support this view (Long. pp. 69-70).
[Thelodonts are small extinct jawless fish with distinctive scales instead of large plates of armour. Placoderms are extinct jawed fish with anterior armour but naked or with scales on the rest of the body.]
The lack of evidence for their evolution is not due to lack of fossil evidence. Although “sharks are rarely found as complete fossils because their skeletons are made of cartilage” under certain conditions complete fossil sharks are preserved very well. These examples provide scientists with vital information, but usually only about the hard parts, such as teeth, scales and fin spines. (Taylor et al. p. 38).
One deposit found last century in Upper Devonian Cleveland shale from the USA yielded entire shark carcasses that were preserved in a bacteria-free environment so that even muscle and kidney tissue could be examined in the rock (Taylor et al. p. 38).
One of the major evidences for ancient sharks is their teeth because “Shark teeth grow in rows from the back and are replaced throughout life … [and] each shark may shed many hundreds of teeth into the oceanic floor sediments. This is why shark teeth are commonly preserved as fossils” (Long. p. 73). Actually, shark teeth are one of the most common fossils found today. In short, sharks were once
regarded as primitive vertebrates—so-called “living fossils”—but recent work suggests that they are highly specialized. Their complex biology ranks them with birds and mammals as highly evolved (Taylor et al. p. 38).
So let us appreciate the sophisticated nature of sharks, a nature which did not arise by chance, but by design.
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