However, the questions of exactly which animal, and how whales evolved from land to water, have remained unanswered until now. In 2000, Dr. Philip D. Gingerich, a paleontologist from the University of Michigan, and his associates discovered two primitive whale fossils in the Balochistan Province of Pakistan. By dating the limestone located in the Habib Rahi Formation of the Balochistan Province, Gingerich estimated these fossils to be about 47 million years old. According to author David Braun of National Geographic News, “The researchers have classified one, Rodhocetus balochistanensis, as a new species of an existing genus, and the other, Artiocetus clavis, as a new species and new genus” (Braun, 5). The discovery of these two fossils suggests that the closest living relative of these primitive whales could possibly be the modern day hippopotamus.
Accessed 5/9/04. Holt, Sidney J.. 2003. “Is the IWC Finished as an Instrument for the Conservation of Whales?” Marine Pollution Bulletin 46: 924-926. Holt, Sidney J.. 2000. “The Whaling Controversy.” Fisheries Research 54: 145-151.
These animals had unusual triangular teeth similar to those of whales. This is why scientists long believed that whales evolved from a form of Mesonychid. More recent molecular phylogeny data suggest that whales are more closely related to the artiodactyls, specifically the hippopotamus. The strong evidence for a clade combining cetaceans and artiodactyls is further discussed in the article “Cetartiodactyla”. However, the anthracothere ancestors of hippos do not appear in the fossil record until millions of years after Pakicetus, the first known whale ancestor(Strauss, no date).
Conclusion: As we have seen, the features of the early tetrapods indicate that they were excellent swimmers but unable to walk on land. The evidence shows that they were descended from a fish ancestor. This means that legs were not evolved for use underwater, and that they adapted for the task of locomotion much later. Evolution always adapts existing structures to perform new purposes, rather than creating new structures. The principle of evolution is sometimes called preadaptation.
Because cartilage does not leave fossil remains like bones, there are no fossils of ancient sharks- just their teeth (Klimley 56). Little is known about great whites because they are enormous, bulky, and hard to handle. And that’s when they’re dead. Their body temperature is sometimes ten to fifteen degrees [Celsius] warmer than the surrounding water, which makes them efficient predators in cool water (Gorman 15). The back of the shark is a dull gray color and the underside is colored white.
Whales are considered to be intelligent mammals, but they live in the water despite the fact that mammals evolved on land. Paleontologist Phil Gingerich has been studying the evolution of whales since 1978. In 1978, he and his team discovered a rock in Pakistan with a skull on the inside. The skull appeared to be a wolf-like animal upon first sight, but Gingerich noticed the distinct whale ear on the skull. The skull, which had characteristics of both whales and other mammals, was that of a common ancestor of the whale known as Pakicetus.
In 1932, Remington Kellogg finally settled the matter with Megatera Novaeangliae (Cousteau 84). The common English name is the hump-back whale.The hump-back whale lives in both the Atlantic and the Pacific oceans. Since we live in the Pacific I'll be discussing the hump-backs of the North Pacific. They migrate from North to South. In the months of July through September they gather in the Aleutian Islands, Bering Sea or the Chukchi Sea.
Science News Online 162 (No. 8): 1-11. 24 Aug. 2002. <http://www.sciencenews.org/articles/20020824/bob10.asp> Pickrell, John. “Ichthyosaur’s Turtle Supper Causes Extinction Debate”.
These findings are important to paleontology as scientists work to discover more about the Earth’s past. These fossils give more insight into the Earth’s environment million’s of years ago. The fact that these fossils may be new species’ that paleontologists were not even aware of shows how little we may know about the history of the world and what other life walked on the Earth.