Primate Origins and Evolution: The First 50 Million Years anthropology

Fossilization requires 2 proper conditions:

1. Interruption of decomposition process

2. Mineralization of bone/cast

Stratigraphy (relative dating)

the study of layers of rock or sediment to determine their relative ages

Biostratigraphy (faunal dating)

Compare fossils to figure out what is older or younger.

absolute dating methods - radiocarbon dating

uses C-14 decay to tell you how old organic material is.

radiometric dating method that measures how much potassium-40 has changed into argon-40 over time.- requires volcanic rock

potassium- argon

Why Did Primates Emerge? : ▪ Arboreal hypothesis

early 1900s, Primates evolved because life in the trees favored better gripping, climbing, and vision.

Why Did Primates Emerge?: Visual predation hypothesis

Cartmill, hunting in trees

Flowering plants spread and provided new food sources, which helped early primates survive and diversify.

Sussman, Angiosperm radiation hypothesis

Vision and nails adapted to life in 3-D environment GE Smith F Wood Jones WE LeGros Clark

Arboreal Hypothesis

M Cartmill , Vision and grasping hands to capture small prey

Visual Predation Hypothesis

RW Sussman, Evolution of flowering plants opened up new niche for primates/ Terminal branch feeding.

Angiosperm Radiation Hypothesis

Paleocene: Plesiadapiforms ex: carpolestes

Early Cenozoic (60 mya) Western North America, Europe

early primate-like mammal that lived about 55–60 million years ago that lived in trees

Carpolestes

Early mammals that had some primate-like features and may have been ancestors of later primates.

proprimates

58 mya in Wyoming

Carpolestes

Diurnal , Sexually dimorphic , Lemurlike

adapids

Nocturnal ,Short snout ,Tarsierlike

Omomyids

55 mya, Small, diurnal, arboreal, insectivorous, Combination of tarsier and anthropoid traits

Archicebus

(“dawn monkey”) • China; 42 mya • Teeth anthropoid-like • Short heel

Eosimias

Biretia

egypt, 37 mya

Oligopithecids

35 mya Early primates that lived in trees and had features similar to modern primates.

Parapithecids have

2/1/3/3 dental formula

an early group of anthropoid primates that lived during the Oligocene.

Propliopithecids

Fayum; 32 mya • Arboreal quadruped • Teeth are apelike • Limbs are monkeylike • Monkey/ape ancestor

Aegyptopithecus

Saudi Arabia; 28 mya • Larger than Aegyptopithecus • Precedes split between Old World monkeys and apes

Saadanius

apes and humans “Planet of the Apes” • Starting in Africa, there is an adaptive radiation of apes 22 mya.

hominoids

(“early apes”; 17–22 mya) • Y-5 molars, fruit-eating, honing canines • No tail

Proconsulids

(8–14 mya) • Pakistan and India • Thick enamel on teeth; hardfood eater • Orangutan-like skull; proconsulid-like body

Sivapithecids

an extinct ape that lived in Asia during the Miocene, about 6-9 million years ago.

Khoratpithecus

Gigantopithecus

A very large extinct ape that lived in Asia.