During which epoch did the first true primates (order Primates) appear in the fossil record?

• A. Cretaceous
• B. Pleistocene
• C. Eocene
• D. Miocene

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the context of the question. The problem is asking about the epoch during which the first true primates appeared in the fossil record. This requires knowledge of evolutionary biology and the geological time scale.
2. Step 2: Recall the geological time scale, which is divided into eons, eras, periods, and epochs. The epochs relevant to this question include the Cretaceous (part of the Mesozoic Era), the Eocene (part of the Paleogene Period in the Cenozoic Era), the Miocene (part of the Neogene Period in the Cenozoic Era), and the Pleistocene (part of the Quaternary Period in the Cenozoic Era).
3. Step 3: Review the evolutionary timeline of primates. True primates (order Primates) are believed to have evolved during the Eocene epoch, approximately 56 to 34 million years ago. This is supported by fossil evidence, such as early primate species like Adapiforms and Omomyids.
4. Step 4: Compare the epochs listed in the question. The Cretaceous epoch predates the evolution of mammals, including primates. The Miocene and Pleistocene epochs occurred much later, after the first true primates had already appeared. The Eocene epoch aligns with the emergence of true primates in the fossil record.
5. Step 5: Conclude that the correct epoch for the appearance of the first true primates in the fossil record is the Eocene, based on the evolutionary timeline and fossil evidence.