
Concept explainers
Why is the fossil record incomplete?
a. | Because many organisms with soft body parts never fossilize. |
b. | Because many fossils are destroyed by geological events |
c. | Because many fossils are buried where no one will ever find them |
d | All of the above are correct. |

Introduction:
Fossils are dead remains of the organism that existed during prehistoric times. Fossil study helps in the estimation of the evolutionary relationship among the organism. These also provide information about the nature of climatic condition during early periods of the Earth’s history.
Answer to Problem 1MCQ
Correct answer:
Many organisms with soft body parts never fossilize, many fossils are destroyed by the geological events, and some fossils are present where no one can locate them. This is the reason for the incomplete fossil records. Hence, the correct answer is option d.
Explanation of Solution
Reason for correct answer:
Option d. is given as, “All of the above are correct.”
Fossil records are incomplete because many organisms with soft body parts never become fossilized, some fossils are destroyed during geological events such as continental drifts, and many fossils are buried at places where no one can ever find them.
Reason for incorrect answer:
Option a. is given as, “because many organisms with soft body parts never fossilize.”
The organism with soft body parts such as sponges and algae never fossilize because the soft body of the organism often mixes with the sediments. However, this is not the only reason for the incomplete fossil records. Hence, option a. is incorrect.
Option b. is given as, “because many fossils are destroyed by geological events.”
The major geologic events such as the movement of continental plates and glacier retreat destroy the fossils. This is one of the reasons that fossil records are incomplete. Hence, option b. is incorrect.
Option d. is given as, “because many fossils are buried where no one will ever find them.”
Many fossils of the aquatic organism are buried under the deep oceanic levels and are difficult to study. However, this is just one of the reasons for fossil records to be incomplete.
Hence, option c. is incorrect.
Hence, the options a., b., and c. are not incorrect but incomplete.
Fossil records are incomplete because many of the organisms with soft body parts never fossilize, many fossils destroyed by the geological events, and many fossils are present where no one can locate them. Thus, the correct option is d.
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Chapter 13 Solutions
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