M. eothen and M. simpsoni are two extinct species of early primates known from fossil records. Belonging to the genus Mahgarita, they inhabited North America during the Eocene epoch. These small, arboreal primates had adaptations for life in the trees, such as grasping hands and feet. Their diet likely consisted of fruits and insects, and they played a role in the ancient ecosystems as seed dispersers and prey for larger predators.

M. eothen and M. simpsoni are prehistoric species, thus their native regions are derived from fossil records. M. eothen fossils have been found in Asia, specifically in regions that are currently part of China. M. simpsoni fossils have been discovered in North America, particularly in areas that were part of the ancient Western Interior Seaway.

M. eothen lived during the Paleocene epoch in a tropical to subtropical climate, characterized by warm temperatures and abundant vegetation. This period was marked by the recovery of ecosystems after the Cretaceous-Paleogene extinction event. M. simpsoni inhabited the Eocene epoch, a time of significant global warming, with warm, moist environments that fostered lush forests and diverse plant life.

Both species were part of early mammalian ecosystems, occupying niches that likely involved omnivorous diets, feeding on a combination of plant material and small animals. They were adapted to forested environments, utilizing their ecological niches to exploit available resources post-dinosaur extinction.