question: Why are some scientists uncertain about the fossil record ?
answer: how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections .
turker_answer: Some scientists are uncertain about the fossil record because of how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections .
rule-based: Some scientists are uncertain about the fossil record because how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections .