As we discussed, plesiadapiforms were initially interpreted as being the first primates. They were then interpreted as being outside the direct primate lineage because they lacked many of the key traits that define the primate order. This debate continues today. Given what you know about the defining traits found in most living primates, describe four traits you think should be found in the earliest primates. What advantages would these traits have provided the first primates? Are any of these traits found in plesiadapiforms? (Use resources in your classroom, credible online sources, or books to help you.)