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Transitional forms to support the theory of evolution are difficult to find, especially in the case of marine mammals. The currently favored evolutionary series begins with a medium sized wolf-like ungulate, to a large sea lion, to a 50 foot long serpent, and finally to the modern whale. Phylogenetic EvidenceThe Cetacea family includes toothed whales, baleen whales and dolphins. Because the differences between cetaceans and land mammals are so great, evolutionists have a difficult task in locating the land mammal whose descendants may have evolved into whales. Based on dental and cranial similarities, the Mesonychids are thought to be the whale's closest land relative. Mesochynids are extinct carnivores that resembled modern even-toed ungulates (cattle, pigs, and camels). The Mesonychids were hoofed, wolf-like creatures approximates eight feet in length. One hypothesis of whale evolution is that the search for food led the Mesonychids to adapt to a life in the sea, chasing food. Subsequent evolutionary adaptations allowed its descendants to become better swimmers and hence better at hunting marine life, eventually giving up its terrestrial lifestyle altogether. If the cetaceans evolved from this primitive ungulate, one would expect all of the non-"whale-specific" traits to be inherited successively without major change. After all, why "reinvent the wheel" if the basic mammalian features are fully functional (i.e. - blood, milk production, etc.). Interestingly, at the DNA level modern whales share characteristics with hippos and not ungulates. Recent research would indicate that whale DNA is more similar to hippos than to ungulates. "If the phylogeny favored by fossil evidence is accepted, the convergence at the DNA level between Cetacea and Hippopotamidae is remarkable in its distribution across three genetic loci: Paleontological Evidence Pakicetus inachus—dated at 52 m.y.a., only a partial skull and teeth fragments have been found. It is claimed to be the oldest "whale" fossil. Although the teeth and cranial features are similar to the Mesonychids, the skull lacks the enlarged sinus to maintain consistent pressure during diving and lacks auditory modifications for hearing underwater. The teeth were adapted to possibly feed on carrion, mollusks, or tough vegetable matter. The skull fragments were discovered in river sediments not a marine environment. There is no reason to assume this animal was not a completely terrestrial animal and yet it is placed in the whale family. Ambulocetus natans—dated at 50 m.y.a. was discovered 400 feet above the beds that yielded Pakicetus. Indocetus ramani—dated at 48 m.y.a. this "primitive whale" was found in shallow-water marine deposits. Leg bones of substantial size have been found. Pelvic bones and partial femurs have been unearthed but no foot bones. The legs were presumably functional both on land and in the sea. It could easily support its own weight while on land, the tibia differs little from that of the fully terrestrial mesonychid Pachyaena ossifraga. Rodhocetus kasrami—dated at 46-47 m.y.a., it was first reported in 1994 as an archaeocete that was intermediary between land mammals and whales. The skeleton would suggest that it could support its weight on land and was also an efficient swimmer. The hind legs are smaller and probably did not help in swimming. The lower backbone was unfused which could have assisted in up and down movement for propulsion through the water. Basilosaurus—dated at 44 m.y.a., this genus includes two species, 1 discovered in the United States, the other in Egypt. In 1990, the discovery of a site containing several hundred partial skeletons of B. isis was reported in Egypt. From this site they were able to piece together an almost complete set of leg and hipbones. Basilosaurus was a very long (50 feet) and slender serpentine creature that led a completely aquatic life. At two feet long, the hind legs are only 3% of the body length and would not have supported the body weight on land. While evolutionists contend that these apparently "useless" legs were only vestigial, their function remains a mystery. We do know that pelvic bones serve as attachments for reproductive organs in modern whales. Fossils of modern whales have been dated at 40 m.y.a. leaving a mere 12 - 15 million years for the Mesonyx to evolve into the modern whale. It stretches the imagination to conceive of the multitude of changes that would have to have occurred in that relatively short amount of time, and then for the whale to change relatively little in the past 40 million years. The change from a small wolf-like land mammal to a 100-foot long completely aquatic whale is not just a matter of size difference. Whales possess very specialized morphologic and physiologic adaptations as well as behaviors that allow them to thrive in a marine environment, even to depths of up to 10,000 feet. "The sperm whale has a huge chamber containing several hundred gallons of sperm oil, or spermaceti, which alters according to depth and temperature to permit adjustment in buoyancy. Before diving, this whale goes through a ten-minute breathing exercise in order for its muscles, blood, and lungs to store oxygen. Its blood contains 50% more hemoglobin than human blood, and while humans use only 10 - 20% of their breathed air for energy, this whale can utilize 80 - 90%."[2] Whales also have an echolocation system that can hear sounds under water from sixty miles away. Reproduction is specialized for underwater birth and nursing. Baleen whales can filter enormous amounts of seawater to abstract tiny plankton. Blue whale, for instance, can intake seventy tons of water at one time. The evidence in the case of whales certainly favors creation over the theory of evolution. The debate as to the ancestor of whales (ungulates or hippopotami) seems mute in comparison to the colossal task of evolving the specialized traits found in whales. The debate becomes even more complicated when you add in the origins of other marine mammals such as walruses, manatees, and seals.
2. Gish, Duane T. 1995. Evolution: The Fossils Still Say NO! Institute for Creation Research, El Cajon, CA. p. 206. Return to Text 3. "Life in the ancient seas" (Basilosaurus at the Smithsonian) 4. "Primitive Eocene Whales" 5. "The Overselling of Whale Evolution" |
, the linked milk casein genes, and mitochondrial cytochrome b."