Which of the following is documented by the fossil record?

• A. The current population sizes of living species
• B. The behavioral habits of all extinct species
• C. The exact DNA sequences of ancient organisms
• D. The appearance and extinction of species over time

Answer: (D)

Verified step by step guidance

1. Understand the role of the fossil record: Fossils are preserved remains or traces of organisms from the past, and they provide evidence of the history of life on Earth.
2. Clarify what the fossil record documents: The fossil record primarily shows the appearance and extinction of species over time, as it captures snapshots of organisms that existed during specific geological periods.
3. Eliminate incorrect options: The fossil record does not document current population sizes of living species, as it pertains to past organisms. It also cannot provide exact DNA sequences of ancient organisms, as DNA degrades over time and is rarely preserved in fossils. Additionally, it does not capture the behavioral habits of all extinct species, as behaviors are not typically preserved in fossilized remains.
4. Focus on the correct option: The fossil record is a timeline of biological history, showing when species appeared and when they went extinct, based on the layers of rock and the fossils found within them.
5. Conclude the reasoning: The correct answer is 'The appearance and extinction of species over time,' as this is the primary documentation provided by the fossil record.