Chapter 22- Primates

Evolution of Primates K103

Three Suborder of Primates

Prosimii, Tarsiiformes, and Anthropoidea

Hominins

Human and humanoid ancestors

Human

hominins (hominids) in hominoid group

Lemurs

Suborder Prosimii

Tarsiers

Suborder Tarsiiformes

Gibbons

Lesser apes, Hominoids, and Suborder Anthropoidea

Orangutans, Gorillas, and Chimpanzees

Great apes, part of the family Hominoids, Suborder Anthropoidea

Humans

Hominoids, Suborder Anthropoidea

Hominoid Locomotion

Refers to the various modes of movement used by hominoids, including brachiation in gibbons, knuckle-walking in gorillas and chimpanzees, and bipedalism in humans.

Brachiation

Gibbons and Orangutans, swinging from limb to limb, tree dwellers, similar to doing the monkey bars

Knuckle walking

use arms to assist in quadrupedal walking, chimpanzees and gorillas

Upright

walking on two legs, a defining characteristic of humans and an adaptation for bipedal locomotion. Humans (hominini including current humans)

Toe alignment

Humans- first toe aligned and not opposable

Gorillas- first toe not aligned and is opposable

Pelvis

Humans- short, broad

Gorillas- long, oval

Vertebral column

Humans- 4 curves

Gorillas- one simple curve

Foramen magnum

Humans- base of skull

Gorillas- rear of skull

Jaw

Human- u-shaped

Gorillas- rectangular

Pronounced facial feature

Humans- chin

Gorillas- supraorbital ridge

Tail

Old World Monkeys- no prehensile tail

New World Monkeys- prehensile tail

Prehensile Tail

use tail as another limb to grasp things such as tree branches

Nose

Old World Monkeys- narrow, with downward nostrils

New World Monkeys- flat, widespread nostrils

Terrestrial vs arboreal

Old World Monkeys- both

New World Monkeys- arboreal

Arboreal

referring to animals that live primarily in trees, adapted for life in the canopy.

Quadrupedal movement

Old World Monkeys- yes

New World Monkeys- no

Stereoscopic vision

seeing an object at the same time with both eyes in the same plan with a slightly different perspective gives depth perception, width, height, etc.

Most recent species of hominids

Homo neanderthalensis, heidelbergenesis, and sapiens

Quadrupedal movement

moving on all four limbs