EARTH SCIENCE
FOSSILS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Slowly, minerals in the water replace the bone.
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Sediment covers the bone.
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An animal dies.
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The bone is no longer a bone, but a rock copy.
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Detailed explanation-1: -The first step in becoming a fossil is death. Natural causes, such as predation or disasters could have killed creatures that lived long ago (just as happens today). The second step involves the animal being buried in sediment, preventing it from being eaten by scavengers or decomposed by bacteria.
Detailed explanation-2: -These clusters of specialized, cooperating cells eventually became the first animals, which DNA evidence suggests evolved around 800 million years ago. Sponges were among the earliest animals.
Detailed explanation-3: -1 Rock hardens and form a fossil. 2 Animal dies and have to be quickly buried. 3 Minerals fill the mold to form a cast fossil. 4 Water dissolves the soft parts leaving a fossil mold.
Detailed explanation-4: -The hard parts of organisms, such as bones, shells, and teeth have a better chance of becoming fossils than do softer parts. One reason for this is that scavengers generally do not eat these parts. Hard parts also decay more slowly than soft parts, giving more time for them to be buried.