Station 1: The Paleocene – Plesiadapiforms, the Stem Primates (2 pt.)The Order Primates includes all living primates and their extinct relatives back to the last common ancestor of strepsirrhines and haplorhines (“crown primates”). It also includes the now extinct plesiadapiforms (“stem primates”). Although plesiadapiforms are not the direct ancestors of living primates, their close relationship with the last common ancestor of living primates can tell us important information about early primate traits. (See the figure on Page 1.)1.Compare and record the dental formulae of the plesiadapiform cast and the galago (a strepsirrhine). (Note:the plesiadapiform has procumbent incisors(not a toothcomb) and the galago has a toothcomb which includes its 1stcanine.)
2.Look at the handout on the plesiadapiform Carpolestes simpsoni. Does the hallux (big toe) of Carpolesteshave more symplesiomorphicfeatures shared with the tree shrew, or synapomorphicfeatures shared with the euprimate? List at least one feature you considered.