One creationist Web site ( /C/cs/evid1.htm) declares that "there are no transitional forms," adding: "For example, not a single fossil with part fins part feet has been found. They said this should undercut the creationists' argument that there is no evidence in the fossil record of one kind of creature becoming another kind. Shubin's team played down the fossil's significance in the raging debate over Darwinian theory, which is opposed mainly by some conservative Christians in the United States, other scientists were not so reticent. A good fossil cuts through a lot of scientific argument." This may be a critical phase in that transition that we haven't had before. Novacek, a paleontologist at the American Museum of Natural History in Manhattan, who was not involved in the research, said: "Based on what we already know, we have a very strong reason to think tetrapods evolved from lineages of fishes. Jenkins Jr., a Harvard evolutionary biologist. Daeschler of the Academy of Natural Sciences in Philadelphia and Farish A. Shubin, the principal discoverers were Edward B. The science foundation and the National Geographic Society were among the financial supporters of the research.
Richard Lane, director of paleobiology at the National Science Foundation, said in a statement, "These exciting discoveries are providing fossil 'Rosetta Stones' for a deeper understanding of this evolutionary milestone  fish to land-roaming tetrapods." Clack said the fish "confirms everything we thought and also tells us about the order in which certain changes were made." In a statement by the Science Museum of London, where casts of the fossils will be on view, Dr. Shubin's team in the search for intermediate species in the evolution from fish to the first animals to colonize land. Clack of the University of Cambridge in England, are often viewed as rivals to Dr. The writers, Erik Ahlberg of Uppsala University in Sweden and Jennifer A. But Tiktaalik is so clearly an intermediate "link between fishes and land vertebrates," they said, that it "might in time become as much an evolutionary icon as the proto-bird Archaeopteryx," which bridged the gap between reptiles, probably dinosaurs, and today's birds. Two other paleontologists, commenting on the find in a separate article in the journal, said that a few other transitional fish had been previously discovered from approximately the same Late Devonian time period, 385 million to 359 million years ago. "It's a really amazing remarkable intermediate fossil  it's like, holy cow," he enthused. Shubin, an evolutionary biologist, let himself go in an interview. Shubin of the University of Chicago wrote, "The origin of limbs probably involved the elaboration and proliferation of features already present in the fins of fish such as Tiktaalik."ĭr. In two reports in Thursday's issue of the journal Nature, the science team led by Neil H. Tiktaalik (pronounced tic-TAH-lick) means "large shallow water fish." The fish has been named Tiktaalik roseae, at the suggestion of elders of Canada's Nunavut Territory. The discovering scientists called the fossils the most compelling examples yet of an animal that was at the cusp of the fish-tetrapod transition. The fish also had a flat skull resembling a crocodile's, a neck, ribs and other parts that were similar to four-legged land animals known as tetrapods. There are the beginnings of digits, proto-wrists, elbows and shoulders. The scientists described evidence in the forward fins of limbs in the making. The skeletons have the fins and scales and other attributes of a giant fish, four to nine feet long.īut on closer examination, scientists found telling anatomical traits of a transitional creature, a fish that is still a fish but exhibiting changes that anticipate the emergence of land animals  a predecessor thus of amphibians, reptiles and dinosaurs, mammals and eventually humans. Several well-preserved skeletons of the fossil fish were uncovered in sediments of former stream beds in the Canadian Arctic, 600 miles from the North Pole, it is being reported on Thursday in the journal Nature. In addition to confirming elements of a major transition in evolution, the fossils are widely seen by scientists as a powerful rebuttal to religious creationists, who hold a literal biblical view on the origins and development of life. Scientists have discovered fossils of a 375 million-year-old fish, a large scaly creature not seen before, that they say is a long-sought "missing link" in the evolution of some fishes from water to a life walking on four limbs on land.
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