Carpolestidae
Encyclopedia
Carpolestidae is a family of primate-like Plesiadapiformes
Plesiadapiformes
Plesiadapiformes is an extinct order of mammals. It is either closely related to the primates or a precursor to them. Many are too derived to be ancestral to primates, but the earliest Plesiadapiformes have teeth that are strongly indicative of a common ancestor...

 that were prevalent in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

 from the mid Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...

 through the early Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

. Typically, they are characterized by two large upper posterior premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...

s and one large lower posterior premolar. They weighed about 20-150g, and were about the size of a mouse
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...

. Though they come from the order, Plesiadapiformes, that may have given rise to the primate order, carpolestids are too specialized and derived to be ancestors of primates.

Historically, the almost twenty species included within the family were thought to have given rise to each other over time in a linear and straightforward manner. Still today it is widely assumed that Elphidotarsius from the mid to late Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...

 gave rise to Carpodaptes which lived in the late Paleocene and subsequently gave rise to Carpolestes
Carpolestes
Carpolestes is a genus of extinct primate-like mammals from the late Paleocene of North America. It first existed around 58 million years ago. The three species of Carpolestes appear to form a lineage, with the earliest occurring species, C. dubius, ancestral to the type species, C. nigridens,...

from the early Eocene. As a result, they have been used as biostratigraphic indicators in a variety of paleontological digs. However, the phylogenetic picture has been complicated by the discovery in Asia of both ancestral and derived carpolestids in the same stratigraphic layer.
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