EARTH SCIENCE
PALEONTOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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salt water
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Fresh water and jawed fish
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no jawed
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None of the above
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Detailed explanation-1: -Jawed fish now seem to have originated as early as the Great Ordovician Biodiversification, a period around 485 million to 445 million years ago when marine invertebrates ruled.
Detailed explanation-2: -Jawed Fish 1. Figure 12.6: The acanthodians were the first and oldest fish with jaws. Acanthodians first appeared during the Silurian and survived until Permian time.
Detailed explanation-3: -By the end of the Silurian Period, a new group of fish had appeared both in freshwater and oceans-the so-called jawed fish. These fish had scales and abundant sharp, spiny fins. Their jaws indicate that they must have been effective predators.
Detailed explanation-4: -Prehistoric armoured fishes called placoderms were the first fishes to have jaws. They arose some time in the Silurian Period, about 440 million years ago, to become the most abundant and diverse fishes of their day.