Overview of the Fossil Primates

Map Showing Location of the Fossil Primates

Map Showing Location of the Fossil Primates

Geologic Timescale

Seven Epochs of the Cenozoic (65.5 - 0 mya) Paleocene (65 mya; primate-like mammals, aka

Plesiadapiformes) Eocene (55.8 mya; first true primates,

Prosimians) Oligocene (33 mya; early Catarrhines,

precursors to monkeys and apes, emerge) Miocene (23 mya; monkeys and apes emerge,

first humanlike creatures appear) Pliocene (5.3 mya; early humans diversify) Pleistocene (1.8 mya; early Homo develops) Holocene (0.01 mya; the present epoch)

General Prosimian Characteristics1. Smaller body size.2. Longer snouts with greater emphasis on

smell.3. Eye sockets not completely enclosed in

bone.4. Dental comb.5. Small simple premolars.

General Anthropoid Characteristics7. Nails instead of claws on all digits8. Loss of the artery running through the

middle ear bone9. Fusion of the two sides of the mandible

to form one bone10. Fusion of the two sides of the frontal

bone11. Larger brain (in absolute terms and

relative to body weight)

General Anthropoid Characteristics1. Generally larger body size2. Shorter snouts with greater emphasis on

vision3. Back of eye socket formed by bony plate4. Less specialized dentition, as seen in

absence of dental comb and some other features

5. Larger and more complex premolars6. Derived square-shaped molars with new

cusp

General Prosimian Characteristics6. Primitive triangle-shaped molars.7. Grooming claw.8. Artery running through the middle ear

bone.9. Unfused mandible.10. Unfused frontal bone.11. Smaller brain size relative to body size.

Plesiadapiforms

PlesiadapiformsPlesiadapis features:

Long tailAgile limbsClaws, not nailsRodent-like jaws and teethEyes at side of headLong snoutNo post-orbital bar

CarpolestidsNorth American genera

ElphidotarsiusCarpodaptes Carpolestes

Nearly complete skeleton of Carpolestes discovered in the Clarks Fork Basin of Wyoming. (a) Carpolestes as it was discovered. (b) Reconstructed skeleton (c) Artist’s rendering.

Carpolestes

Nearly complete skeleton of Carpolestes discovered in the Clarks Fork Basin of Wyoming. (a) Carpolestes as it was discovered. (b) Reconstructed skeleton (c) Artist’s rendering.

Eocene Primates Fossil primates from the Eocene display

distinctive primate features. The first unequivocal primates occur about

50 mya. There are two main groups identified:

Adapids which are usually considered to be ancestral to modern Strepsirhines

Omomyids which are (mostly) considered to be early Haplorhines

AdapidsNortharctusAdapisNecrolemurTarsius

Northarctus

Adapis

Oligocene PrimatesThe Oligocene (34–23 m.y.a.) yielded fossil

remains of several species of early anthropoids.By the early Oligocene, continental drift had

separated the New World from the Old World.It has been suggested that late in the Eocene

or very early in the Oligocene, the first anthropoids arose in Africa and reached South America by “rafting” over the water separation on drifting chunks of vegetation.

ParapithecusParapithecus

belongs to the group of Fayum anthropoids that are most closely related to the ancestry of New World monkeys.

AegyptopithecusSkull of

Aegyptopithecus.This genus has

been proposed as the ancestor of both Old World monkeys and hominoids.

HomunculusSkull of

Homunculus, a middle Miocene descendant of the earliest platyrrhine radiation.

VictoriapithecusSkull of

Victoriapithecus, the first Old World monkey.

New World Monkey vs. Old World Monkey CharacteristicsNew World Monkeys1. Sideways facing

nostrils2. Ring-like ear hole

with no tube3. Dental formula of

2.1.3.34. Grasping tail5. Distribution: Mexico

and South America

Old World Monkeys1. Downward facing

nostrils2. Tube-like ear hole3. Dental formula of

2.1.2.34. Ischial callosities5. Distribution: Africa,

southern Asia and Japan

PliopithecusPliopithecus, from the

middle Miocene of Europe.

The pliopithecoids were the first catarrhines to leave Africa.

Since this skull is of a female, no sagittal crest is present, though strong temporal lines indicate the individual enjoyed a diet of hard plant items.

DryopithecusSkull of

Dryopithecus, the earliest European ape.

The left side is reconstructed as a mirror image of the complete right side.

OuranopithecusOuranopithecus,

possible ancestor of the African apes.

Notice that the face shares many features with living African great apes, including large browridges and a wide distance between the eye orbits.

Gigantopithecus

An artist’s rendering of Gigantopithecus enjoying a meal of the tasty, but tough, tropical fruit known as durian.