Vertebrates

Page
8

Slide 54

Lemurs

Slide 55

Most primates have hands and feet adapted for grasping.

Other derived characters of primates:

A large brain and short jaws

Forward-looking eyes close together on the face, providing depth perception

Complex social behavior and parental care

A fully opposable thumb (in monkeys and apes).

Derived Characters of Primates

Slide 56

A phylogenetic tree of primates

Lemurs, lorises,

and pottos

Tarsiers

New World monkeys

Old World monkeys

Gibbons

Orangutans

Gorillas

Chimpanzees

and bonobos

Humans

0

10

20

30

40

50

60

Time (millions of years ago)

ANCESTRAL

PRIMATE

Anthropoids

Slide 57

The first monkeys evolved in the Old World (Africa and Asia).

In the New World (South America), monkeys first appeared roughly 25 million years ago.

New World and Old World monkeys underwent separate adaptive radiations during their many millions of years of separation.

Slide 58

New World monkeys and Old World monkeys

(a) New World monkey

(b) Old World monkey

Slide 59

Nonhuman apes

(e) Bonobos

(a) Gibbon

(d) Chimpanzees

(b) Orangutan

(c) Gorilla

Slide 60

Concept 34.8: Humans are mammals that have a large brain and bipedal locomotion

The species Homo sapiens is about 200,000 years old, which is very young, considering that life has existed on Earth for at least 3.5 billion years.

The study of human origins is known as paleoanthropology.

Hominins (formerly called hominids) are more closely related to humans than to chimpanzees.

Paleoanthropologists have discovered fossils of about 20 species of extinct hominins.

Slide 61

Derived Characters of Humans

A number of characters distinguish humans from other apes:

Upright posture and bipedal locomotion

Larger brains

Language capabilities and symbolic thought

The manufacture and use of complex tools

Shortened jaw

Shorter digestive tract.

Slide 62

A timeline for some selected hominin species

Homo

erectus

Homo

habilis

Homo

sapiens

Homo