GENETICS AND EVOLUTION
EVOLUTION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Bottom
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Top
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Middle
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None of the above
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Detailed explanation-1: -In sedimentary rock the oldest fossils would be expected to be found. fossils would be found in the bottom of the rock, where the smaller rocks have been deposited the longest.
Detailed explanation-2: -The oldest layers are on the bottom, and the youngest layers are on the top. Because sediments sometimes include once-living organisms, sedimentary rock often contains a lot of fossils. Fossils are once-living organisms that have been turned into rock, in which the shape or form of the organism can still be seen.
Detailed explanation-3: -It is based on the Law of Superposition which states that in undisturbed rock sequences the bottom layers are older than the top layers. Therefore, some discovered fossils are able to be dated according to the strata, a distinct layer of rock, that they are found in.
Detailed explanation-4: -The oldest accepted fossils are those from Strelley Pool in the Pilbara region of western Australia. They are stromatolites: preserved mats of microorganisms sandwiched between layers of sediment. The fossils are 3.4 billion years old.
Detailed explanation-5: -The bottom layer of rock forms first, which means it is oldest. Each layer above that is younger, and the top layer is youngest of all. This ordering is relative because you cannot be sure exactly when each layer formed, only that each layer is younger then the one below it.