primate evolution

PRIMATE EVOLUTION

The Paleocene Epoch~65-55 mya

65mya dinosaurs disappear New forest floor niches

Primates diverge from some ancestral insectivore

Tree shrew model Arboreal vs. visual

predation theory

ARCHONTA

Scadentia, Dermoptera (colugos), Plesiadapiformes

Bats are out

Eocene Epoch(~55-35 mya)

Earliest fossils Majority in North America

& Europe but also AsiaProsimian radiation Angiosperm adaptive

radiation / P-E thermal maximum

Adapoidea More primitive Diurnal Medium-sized

arboreal leapers

Frugivory with some folivory

Ancestral to strepsirhines

Omomyoidea

Nocturnal Smaller Arboreal leapers Insectivore/frugivores

and gumnivory Ancestor to tarsiers,

possibly anthropoids

Prosimians spread into Africa Motor to Madagascar Shangiladida!...until humans migrate

Fill variety of niches Bats Woodpeckers

Late Eocene / Early Oligocene

10my of tectonic, climatic, floral/faunal change

Temperatures drop Primates disappear from

NA and Europe High extinctions elsewhere

E-O evolutionary bottleneck

Few fossils Primarily Fayum

AdapoidAdapoidOmomyoidOmomyoidTarsierTarsierAncient/otherAncient/other

ASIA OR NORTH AFRICA?ASIA OR NORTH AFRICA?

Siamopithecus

Eosimias

EosimiasEosimias: The Dawn Monkey: The Dawn Monkey

Prosimians outside Madagascar go extinct, except…

WHY?

Oligocene Epoch (~35-24 mya)

Anthropoid radiation

Three families: I. Parapithecidae

Most primitive Thought ancestral to NW

monkeys

II. Oligopithecidae Intermediate

III. Propliopithecidae Most derived Generalized anthropoid Ancestral to OW anthropoids

Sea level low More exposed

land Continental

shelves Ridges…

Currents Computer

modeling - weeks

NEW WORLD MONKEYS

Apidium

Small, squirrel-sized, leaping arboreal quadruped

2-1-3-3 dental formula

Precede appearance in New World by 10mya

Rodents in NW appear around same time and resemble African porcupine

•Few fossils

•Many have not changed much

OW Anthropoid Phylogeny

Aegyptopithecus / Propliopithecus Note: no tail

OW monkeys likely diverged late Oligocene Adaptive radiation continues

During early period, apes successful and radiation of OW monkeys was slow

Begin to flourish after apes begin to decline

More generalized/successful Derived terrestriality Shorter life stages

Not as tied to forest so survive when apes die out in late Miocene

May have contributed to ape decline

Miocene Epoch(~24-5 mya)

Hominoid Radiation

Evolve in Africa Spread into Eurasia via land bridge ~16mya

Large geographic

range relative to modern

Warmer than Oligocene But seasons more

pronounced Increasing aridification

Rain shadow Forests change Hominoids fill niches

Early Miocene (24-16mya) African Hominoids

Fossils primarily from Kenya and Uganda Multiple genera

Different habitats Tropical to more open

woodland

Different sizes (3-50kg) Some arboreal some derived

terrestrial adaptations for exploiting forest floor (like Pan & Gorilla)

Different locomotor patterns Different morphology Some SHA

Different diets Thick enamel – hard foods Thin enamel – softer foods

Best known Our ancestry Arboreal climbers No SHA Primarily frugivores Sexually dimorphic

~chimps Polygynous

Kenyapithecus or Afropithecus?

Proconsul

HAND/FOREARM OF P. HESELONI

LOWER LEG P.HESELONI, PAN,

and P. NYANZAE

Links to modern hominoids (long bones, no tail) but so primitive, difficult to trace ancestry through any of these early apes.

Proconsul

70-150# Arboreal

quadruped Lacking

SHA

Gigantopithecus

(Size of ♀ gorilla?)

Ancestry of Hylobatidae uncertainpossibly diverged 16-18mya

Mid-Miocene (16-11)Rapid radiation in Eurasia

Dryopithecus

•Few fossils

•Jaws and teeth

•France, Spain, Italy, Greece, Austria

Dental (Oak) apes

LATE MIOCENE (11-5mya)

Greatest diversity of hominoidsEurope: Dryopithecus, Oreopithecus,

OaranopithecusAsia: Ankarapithecus (Turkey), Sivapithecus

(Pakistan), Lufengpithecus (China)Africa: Otavipithecus (Namibia)

NEWSFLASH!!!

Nakalipithecus nakayamai Kenya~10myaPossible missing link