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Updated: Aug 4, 2026
09:09
Dissecting the Non-human Primate Brain in Stereotaxic Space
Published on: July 16, 2009
Summary
Fossil discoveries in Montana, Purgatorius unio and P. ceratops, extend the primate range to the late Cretaceous. These early primates show unique structures, possibly not ancestral to modern primates.
Area of Science:
- Paleontology
- Primate Evolution
Background:
- The fossil record of early primates is sparse.
- Understanding primate origins requires examining the earliest potential candidates.
Purpose of the Study:
- To describe new fossil species that may represent early primates.
- To determine the geological age and phylogenetic position of these new fossils.
Main Methods:
- Paleontological excavation and analysis of fossilized remains.
- Comparative anatomical study with other early mammals.
- Stratigraphic analysis to determine age.
Main Results:
- Discovery of a new genus, Purgatorius, with two new species: P. unio and P. ceratops.
- These fossils extend the known primate range into the late Cretaceous and early Paleocene.
- Purgatorius exhibits features resembling condylarths and insectivores, and is placed in the new subfamily Purgatoriinae.
- The fauna suggests a late early Paleocene age for the Purgatory Hill site.
Conclusions:
- The discovery of Purgatorius provides new insights into the early evolution and paleobiogeography of primates.
- While Purgatorius is an early primate relative, it is likely not the direct ancestor of all primates.
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